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                                                                    Exhibit 4.01

                               essential.com. inc.

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                          Dated as of February 8, 2000

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                                TABLE OF CONTENTS
                                                                           Page
                                                                           ----

1.     Definitions .......................................................... 1

2.     Demand Registration .................................................. 3

       A.    Demand Rights .................................................. 3
       B.    S-3 Registration Rights ........................................ 4

3.     Company Registration ................................................. 4

4.     Obligations of the Company ........................................... 5

5.     Furnish Information .................................................. 7

6.     Expenses of Registration ............................................. 7

7.     Underwriting Requirements ............................................ 8

8.     Indemnification ...................................................... 8

9.     Reports Under the Exchange Act .......................................10

10.    Assignment of Registration Rights ....................................11

11.    Limitations on Registration Rights ...................................11

12.    "Market Stand-Off' Agreement .........................................11

13.    Amendment; Waiver ....................................................12

14.    Changes in Registrable Securities ....................................12

15.    Information ..........................................................12

       (a)    Financial and Related Data ....................................13
       (b)    Access to Properties ..........................................14

16.    Termination of Registration Rights ...................................14

17.    Legends and Opinions .................................................15

18.    Entire Agreement .....................................................15

19.    Governing Law ........................................................15

20.    Successors and Assigns ...............................................15


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21.    Notices ..............................................................15

22.    Severability .........................................................16

23.    Titles and Subtitles .................................................16

24.    Delays or Omissions; Remedies Cumulative .............................16

25.    Arbitration ..........................................................16

26.    Counterparts .........................................................16

27.    Accession to Agreement ...............................................16


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                  SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

      This Second Amended and Restated Investor Rights Agreement (this
"Agreement") is made as of the 8th day of February, 2000 by and among (i)
essential.com, inc., a Delaware corporation (the "Company"), (ii) those holders
of the Company's Series A Preferred Stock, $.01 par value per share (the "Series
A Stock"), set forth on Schedule I hereto under the heading "Angel Investor"
(the "Angel Investors"), (iii) those holders of Series A Stock and the Company's
Series B Preferred Stock, $.0l par value per share (the "Series B Stock"), set
forth on Schedule I hereto under the heading "Existing Outside Investors" (the
"Existing Outside Investors"), and (iv) those holders of the Company's Series C
Preferred Stock, $.0 1 par value per share (the "Series C Stock"), set forth on
Schedule I hereto under the heading "Series C Investors" (the "Series C
Investors"), as such Schedule shall be amended from time to time to reflect each
person who shall, after the date hereof, acquire shares of capital stock and
join in and become party to this Agreement as a Series C Investor by executing
and delivering to the Company an Instrument of Accession in the form of Schedule
II hereto. The Existing Outside Investors and the Series C Investors are
referred to collectively herein as the "Outside Investors." The Angel Investors
and the Outside Investors are referred to collectively herein as the "Investors"
and each collectively as an "Investor." For purposes of this Agreement, Zafa
shall be entitled to the rights of an Outside Investor set forth herein only to
the extent of his ownership of shares of Series B Stock.

                                    RECITALS:

      A. Concurrently with the execution of this Agreement, the Series C
Investors are acquiring from the Company shares of the Company's Series C Stock,
pursuant to the Series C Convertible Preferred Stock Purchase Agreement of even
date herewith (the "Purchase Agreement").

      B. By entering into this Agreement, the Company wishes to provide a
further inducement to the Series C Investors to purchase the Company's Series C
Stock pursuant to the Purchase Agreement.

            NOW, THEREFORE, in consideration of the foregoing, the parties agree
as follows:

            1.    Definitions. For purposes of this Agreement:

      (a) "Common Shares" means shares of Common Stock, par value $0.01 per
share, of the Company.

      (b) "Exchange Act" means the Securities Exchange Act of 1934, as amended.

      (c) "Form S-3" means such form of registration statement under the
Securities Act as in effect on the date hereof or any registration form under
the Securities Act subsequently adopted by the SEC which permits inclusion or
incorporation of substantial information by reference to other documents filed
by the Company with the SEC.


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      (d) "Holder" means any Person owning or having the right to acquire
Registrable Securities, or any assignee thereof in accordance with Section 11.

      (e) "Initiating Holders" means the Holder(s) initiating a registration
request under Section 2.

      (f) "Majority in Interest of the Initiating Holders" means Initiating
Holders holding a majority of the Registrable Securities held by all Initiating
Holders.

      (g) "Person" means any individual, partnership, limited liability company,
joint venture, corporation, association, trust or any other entity or
organization.

      (h) "Preferred Stock" means collectively, the Series A Stock, the Series B
Stock and the Series C Stock.

      (i) "Qualifying Request" means a written request to register Registrable
Securities with a reasonably anticipated aggregate offering price in excess of
$5,000,000 from any of the Investors that in the aggregate possess either (i) at
least fifty percent (50%) of the Registrable Securities outstanding as of the
date of such request or (ii) at least fifty percent (50%) of the Registrable
Securities issued or issuable upon conversion of the Series C Stock and held by
the Series C Investors or their successors, assigns or donees on the date of
such request.

      (j) "Register," "registered," and "registration" refer to a registration
effected by preparing and filing a registration statement or similar document in
compliance with the Securities Act, and the declaration or ordering of
effectiveness of such registration statement or document.

      (k) "Registrable Securities" means (1) any Common Shares issuable (without
regard to any restriction on conversion that may be applicable to any particular
holder of Preferred Stock) or issued upon conversion of the Preferred Stock; (2)
any Common Shares issued as (or issuable upon the conversion or exercise of any
warrant, right or other security which is issued as) a dividend or other
distribution with respect to, or in exchange for or in replacement of, or upon
conversion of, such Preferred Stock; and (3) any other capital stock of the
Company whether now owned or hereafter acquired upon the conversion of, exchange
for, or in replacement of, Preferred Stock; provided, however, that any
Registrable Securities sold by a Person in a transaction in which such Person's
rights under this Agreement are not assigned pursuant to Section 11 below shall
cease to be Registrable Securities from and after the time of such sale.

      (l) The number of shares of "Registrable Securities then outstanding"
shall be determined by the number of Common Shares outstanding, and the number
of Common Shares issuable, which are Registrable Securities.

      (m) "SEC" means the Securities and Exchange Commission.

      (n) "Securities Act" means the Securities Act of 1933, as amended.


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      (o) "Series C Qualifying Request" means a Qualifying Request from the
Series C Investors pursuant to (ii) in the definition of Qualifying Request
contained in this Section 1.

      (p) "Violation" means any of the following statements, omissions or
violations: (i) any untrue statement or alleged untrue statement of a material
fact contained in a registration statement under this Agreement, including any
preliminary prospectus or final prospectus contained therein or any amendments
or supplements thereto or any documents filed under state securities or "blue
sky" laws in connection therewith, (ii) the omission or alleged omission to
state therein a material fact required to be stated therein, or necessary to
make the statements therein not misleading; or (iii) any violation or alleged
violation by the Company of the Securities Act, the Exchange Act, any state
securities law or any rule or regulation promulgated under the Securities Act,
the Exchange Act or any state securities law.

            2. Demand Registration.

            A. Demand Rights.

            (a) If, after the earlier of (i) one hundred eighty (180) days after
the consummation of the initial public offering of the Company's Common Stock,
or (ii) March 29, 2002, the Company shall receive a Qualifying Request that the
Company file a registration statement under the Securities Act with respect to
Registrable Securities then outstanding, then the Company shall, subject to the
limitations of Section 2A(b) below, use its best efforts to effect as soon as
practicable, and in any event within ninety (90) days of the receipt of such
Qualifying Request, such registration. Notwithstanding the foregoing, the
Company shall not be obligated to effect any such registration within 6 months
after the effective date of an immediately preceding registration pursuant to
this Section 2A. The Company shall be obligated to effect only two (2)
registrations pursuant to this Section 2A (an offering which is not consummated
shall not be counted for this purpose).

            (b) If Initiating Holders intend to distribute the Registrable
Securities covered by their request by means of an underwriting, they shall so
advise the Company as a part of their request made pursuant to this Section 2A.
In such event, the right of any Holder to include such Holder's Registrable
Securities in such registration shall be conditioned upon such Holder's
participation in such underwriting and the inclusion of such Holder's
Registrable Securities in the underwriting (unless otherwise mutually agreed by
a Majority in Interest of the Initiating Holders and such Holder) to the extent
provided herein. The Company shall select the managing underwriter or
underwriters in such underwriting, such underwriter(s) to be reasonably
satisfactory to a Majority in Interest of the Initiating Holders. All Holders
proposing to distribute their securities through such underwriting shall
(together with the Company as provided in Section 4(f)) enter into an
underwriting agreement in customary form with the underwriter or underwriters so
selected for such underwriting by a Majority in Interest of the Initiating
Holders; provided, however, that the Company shall use commercially reasonable
efforts to negotiate with the underwriters to assure that none of the Holders
shall be required to make any representations or warranties or provide
indemnification except as relates to such Holder's ownership of shares and
authority to enter into the underwriting agreement and to such Holder's intended
method of distribution, and the liability of such Holder shall be limited to an
amount equal to the net proceeds from the offering received by such Holder. In
the event that the underwriters advise the


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Company that marketing factors require a limitation of the number of shares to
be underwritten, the Company and its underwriters shall allocate the number of
Registrable Securities requested to be registered by each of the Holders as
follows: (i) first, to the Outside Investors holding Registrable Securities that
have elected to participate in such offering, pro rata according to the number
of Registrable Securities held by each such Outside Investor; and (ii)
thereafter, to the extent additional securities may be included in such
offering, to the Angel Investors holding Registrable Securities that have
elected to participate in such underwritten offering, pro rata according to the
number of Registrable Securities held by each such Angel Investor; provided,
however, that if the Qualifying Request is a Series C Qualifying Request, and in
the event that the underwriters advise the Company that marketing factors
require a limitation of the number of shares to be underwritten, the Company and
its underwriters shall allocate the number of Registrable Securities requested
to be registered by each of the Holders as follows: (i) first, to the Series C
Investors holding Registrable Securities that have elected to participate in
such offering, pro rata according to the number of Registrable Securities held
by each such Series C Investor; (ii) second, to the Outside Investors (other
than the Series C Investors) holding Registrable Securities that have elected to
participate in such offering, pro rata according to the number of Registrable
Securities held by each such Outside Investor (other than the Series C
Investors); and (iii) thereafter, to the extent additional securities may be
included in such offering, to the Angel Investors holding Registrable Securities
that have elected to participate in such underwritten offering, pro rata
according to the number of Registrable Securities held by each such Angel
Investor.

            B. S-3 Registration Rights.

            The Company shall be obligated to effect up to two (2) registrations
pursuant to this Section 2B as may be requested by the Investors in the event
and so long as a registration statement pursuant to Form S-3 or any similar
"short-form" registration (a "Short-Form Registration") is available for such
Registration, provided further, that the reasonably anticipated aggregate
offering price will be in excess of $1,000,000. The Company shall not be
obligated to effect a Short Form Registration more than once in any six-month
period.

            C. Notwithstanding the foregoing provisions of Sections 2A and 2B,
if the Company shall furnish to Holders requesting a registration statement
pursuant to this Section 2, a certificate signed by the President of the Company
stating that, in the good faith judgment of the Board of Directors of the
Company, it would be detrimental to the Company and its shareholders for such
registration statement to be filed by reason of a material pending announcement
or transaction or series of pending transactions and it is therefore necessary
to defer the filing of such registration statement, the Company shall have the
right to defer such filing for a period of not more than one hundred eighty
(180) days after receipt of the request of the Holders; provided, however, that
the Company may not utilize this right more than once in any twelve (12) month
period.

            3. Company Registration. If (but without any obligation to do so)
the Company proposes to register (including for this purpose a registration
effected by the Company for shareholders) any of its stock or other securities
under the Securities Act in connection with a public offering of such securities
solely for cash other than (i) a registration on Form S-8 (or other similar
successor form) relating solely to the sale of securities to participants in a
Company


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stock plan or to other compensatory arrangements to the extent includable on
Form S-8 (or other similar successor form), or (ii) a registration on Form S-4
(or other similar successor form), the Company shall, at such time, promptly
give each Holder written notice of such registration. Upon the written request
of each Holder given within twenty (20) days after mailing of such notice by the
Company in accordance with Section 22, the Company shall, subject to the
provisions of Section 7, use its best efforts to cause to be registered under
the Securities Act all of the Registrable Securities that each such Holder has
requested to be registered. In the event that the underwriters advise the
Company that marketing factors require a limitation of the number of shares to
be underwritten, the Company and its underwriters shall allocate the number of
Registrable Securities requested to be registered by each of the Holders as
follows: (i) first, to the Company; (ii) second, to the Outside Investors
holding Registrable Securities that have elected to participate in such
offering, pro rata according to the number of Registrable Securities held by
each such Outside Investor; and (iii) thereafter, to the extent additional
securities may be included in such offering, to the Angel Investors holding
Registrable Securities that have elected to participate in such underwritten
offering, pro rata according to the number of Registrable Securities held by
each such Angel Investor; provided, however, that in no event shall the number
of Registrable Securities to be registered by the Outside Investors be less than
twenty percent (20%) of the total number of shares to be sold in such offering.
The Company shall have no obligation under this Section 3 to make any offering
of its securities, or to complete an offering of its securities that it proposes
to make, and shall incur no liability to any Holder for its failure to do so.

            4. Obligations of the Company. Whenever required under this
Agreement to effect the registration of any Registrable Securities, the Company
shall, as expeditiously as reasonably possible:

            (a) Prepare and file with the SEC a registration statement with
respect to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
of a majority of the Registrable Securities being registered thereunder, keep
such registration statement effective for up to one hundred twenty (120) days or
until the Holders have completed the distribution referred to in such
registration statement, whichever occurs first (but in any event for at least
any period required under the Securities Act); provided that before filing such
registration statement or any amendments thereto, the Company will furnish to
the directors elected by the holders of the Preferred Stock copies of all such
documents proposed to be filed; provided, further, however, that each such
director may elect to waive such requirement by written notice to the Company.

            (b) Prepare and file with the SEC such amendments and supplements to
such registration statement and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement.

            (c) Furnish to the Holders such number of copies of such
registration statement and of each amendment and supplement thereto (in each
case including all exhibits), such number of copies of the prospectus contained
in such registration statement (including each preliminary prospectus and any
summary prospectus) and any other prospectus filed under Rule 424 under the
Securities Act, in conformity with the requirements of the Securities Act, and
such


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other documents as Holders may reasonably request in order to facilitate the
disposition of Registrable Securities owned by them.

            (d) Use commercially reasonable efforts to register and qualify the
securities covered by such registration statement under such other securities or
"blue sky" laws of such states or jurisdictions as shall be reasonably requested
by the Holders, provided that the Company shall not be required in connection
therewith or as a condition thereto (i) to qualify to do business in any state
or jurisdiction where it would not otherwise be required to qualify but for the
requirements of this clause (d), or (ii) to file a general consent to service of
process in any such state or jurisdiction.

            (e) Use commercially reasonable efforts to cause all Registrable
Securities covered by such registration statement to be registered with or
approved by such other governmental agencies or authorities as may be necessary
by virtue of the Company's business or operations to enable the seller or
sellers thereof to consummate the disposition of such Registrable Securities.

            (f) In the event of any underwritten public offering, enter into and
perform its obligations under an underwriting agreement, in usual and customary
form, with the managing underwriter of such offering.

            (g) Notify each Holder of Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Securities Act of the happening of any event
as a result of which the prospectus included in such registration statement, as
then in effect, includes an untrue statement of a material fact or omits to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading in the light of the circumstances then
existing.

            (h) Notify each Holder of Registrable Securities covered by such
registration statement and such Holder's underwriters, if any, and confirm such
advice in writing: (i) when the registration statement has become effective;
(ii) when any post-effective amendment to the registration statement becomes
effective; and (iii) of any request by the SEC for any amendment or supplement
to the registration statement or prospectus or for additional information.

            (i) Notify each Holder of Registrable Securities if at any time the
SEC should institute or threaten to institute any proceedings for the purpose of
issuing, or should issue, a stop order suspending the effectiveness of the
Registration Statement. Upon the occurrence of any of the events mentioned in
the preceding sentence, the Company will use commercially reasonable efforts to
prevent the issuance of any stop order or to obtain the withdrawal thereof as
soon as possible. The Company will advise each Holder of Registrable Securities
promptly of any order or communication of any public board or body addressed to
the Company suspending or threatening to suspend the qualification of any
Registrable Securities for sale in any jurisdiction.

            (j) Furnish, at the request of any Holder requesting registration of
Registrable Securities pursuant to this Agreement, (i) on the date that such
Registrable Securities are delivered to the underwriters for sale in connection
with any registration pursuant to this Agreement in which securities are being
sold through underwriters, an opinion, dated such date,


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of the counsel representing the Company for the purposes of such registration,
in form and substance as is customarily given to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities and (ii) on the date that the
registration statement with respect to such securities becomes effective, a
"comfort" letter dated such date, from the independent certified public
accountants of the Company, in form and substance as is customarily given by
independent certified public accountants to underwriters in an underwritten
public offering, addressed to the underwriters, if any, and to the Holders
requesting registration of Registrable Securities, and a reaffirmation of such
letter on the date that such Registrable Securities are delivered to the
underwriters for sale.

            (k) As soon as practicable after the effective date of the
registration statement, and in any event within sixteen (16) months thereafter,
have "made generally available to its security holders" (within the meaning of
Rule 158 under the Securities Act) an earning statement (which need not be
audited) covering a period of at least twelve (12) months beginning after the
effective date of the registration statement and otherwise complying with
Section 11(a) of the Securities Act.

            5. Furnish Information. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to this Agreement with
respect to the Registrable Securities of any selling Holder that such Holder
shall furnish to the Company such information regarding itself, the Registrable
Securities held by it, and the intended method of distribution of such
securities as shall be required to effect the registration of such Holder's
Registrable Securities. If any registration statement or comparable statement
under the Securities Act refers to an Investor or any of its affiliates, by name
or otherwise, as the holder of any securities of the Company then, unless
counsel to the Company advises the Company that the Securities Act or the SEC
requires that such reference be included in any such statement, each such
Investor shall have the right to require the deletion of such reference to
itself and its affiliates.

            6. Expenses of Registration. All expenses, other than underwriting
discounts and commissions relating to Registrable Securities, incurred in
connection with registrations, filings or qualifications pursuant to this
Agreement, including without limitation all registration, filing and
qualification fees, printers' and accounting fees, fees and disbursements (up to
$25,000) of one counsel (selected by a majority of Holders participating in such
a registration) for the selling Holders shall be borne by the Company; provided,
however, that the Company shall not be required to bear such expenses in
connection with any registration begun pursuant to Section 2 if the offering is
not consummated primarily as a result of any act or omission of any
participating Holder (in which case all participating Holders shall bear such
expenses pro rata), unless with respect to a demand made pursuant to Section 2,
a Majority in Interest of the Initiating Holders agree to forfeit one (1) of the
demand registration(s) to which they are then entitled pursuant to Section 2;
provided, further, however, that if (i) at the time of such withdrawal, the
Holders have learned of a material adverse change in the financial condition or
business of the Company from that known to the Holders at the time of their
request, or (ii) if such withdrawal is at the request of, caused by, or the
result of an unreasonable delay by the Company, then the Holders shall not be
required to pay any such expenses and shall retain their rights pursuant to
Section 2 of this Agreement.


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            7. Underwriting Requirements. In connection with any offering
involving an underwriting of shares being issued by the Company, the Company
shall not be required under Section 3 to include any Holder's securities in such
underwriting unless such Holder accepts the terms of the underwriting as agreed
upon between the Company and the underwriters selected by the Company (with the
approval of Holders holding a majority of the Registrable Securities held by all
Holders, such approval not to be unreasonably withheld); provided, however, that
no Holder participating in such underwriting shall be required to make any
representations or warranties or provide indemnification except as relates to
such Holder's ownership of shares and authority to enter into the underwriting
agreement and to such Holder's intended method of distribution, and the
liability of such Holder shall be limited to an amount equal to the net proceeds
from the offering received by such Holder.

            8. Indemnification. In the event any Registrable Securities are
included in a registration statement under this Agreement:

            (a) The Company will indemnify and hold harmless each Holder, his or
her heirs, personal representatives and assigns, each of such Holder's partners,
officers, directors, employees and affiliates, any underwriter (as defined in
the Securities Act) for such Holder and each Person, if any, who controls such
Holder or underwriter within the meaning of the Securities Act or the Exchange
Act against any losses, claims, damages or liabilities (joint or several) to
which they may become subject under the Securities Act, the Exchange Act or
other federal or state law, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon a
Violation (provided, however, that the Company will not be required to indemnify
any of the foregoing Persons on account of any losses, claims, damages or
liabilities arising from a Violation if and to the extent that such Violation
was made in a preliminary prospectus and was corrected in a subsequent
prospectus that was required by law to be delivered to the Person making the
claim with respect to which indemnification is sought hereunder, and such
subsequent prospectus was made available by the Company to permit delivery of
such prospectus in a timely manner, and such subsequent prospectus was not so
delivered to such Person by a selling stockholder making use of a prospectus
from a Registration Statement on Form S-3); and the Company will pay to each
such indemnified party, as incurred, any legal or other expenses reasonably
incurred by them in connection with investigating or defending any such loss,
claim, damage, liability, or action; provided, however, that the indemnity
agreement contained in this Section 8(a) shall not apply to amounts paid in
settlement of any such loss, claim, damage, liability or action if such
settlement is effected without the consent of the Company (which consent shall
not be unreasonably withheld), nor shall the Company be liable in any such case
to a particular indemnified party for any such loss, claim, damage, liability or
action to the extent that it arises out of or is based upon a Violation which
occurs in reliance upon, and in conformity with, written information furnished
expressly for use in connection with such registration by or on behalf of such
indemnified party.

            (b) Each selling Holder will indemnify and hold harmless the
Company, each of its directors, each of its officers who has signed the
registration statement, each Person, if any, who controls the Company within the
meaning of the Securities Act, any underwriter, any other Holder selling
securities in such registration statement and any controlling Person of any such
underwriter or other Holder, against any losses, claims, damages or liabilities
(joint or several) to which any of the foregoing Persons may become subject,
under the Securities Act, the Exchange


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Act or other federal or state law, insofar as such losses, claims, damages or
liabilities (or actions in respect thereto) arise out of or are based upon any
Violation, in each case to the extent (and only to the extent) that such
Violation occurs in reliance upon and in conformity with written information
furnished by or on behalf of such Holder expressly for use in connection with
such registration; and each such Holder will pay, as incurred, any legal or
other expenses reasonably incurred by any Person intended to be indemnified
pursuant to this Section 8(b), in connection with investigating or defending any
such loss, claim, damage, liability, or action; provided, however, that the
indemnity agreement contained in this Section 8(b) shall not apply to amounts
paid in settlement of any such loss, claim, damage, liability or action if such
settlement is effected without the consent of the Holder, which consent shall
not be unreasonably withheld; and provided further, that, in no event shall the
liability of any Holder under this Section 8(b) exceed the net proceeds from the
offering received by such Holder.

            (c) Promptly after receipt by an indemnified party under this
Section 8 of notice of the commencement of any action (including any
governmental action), such indemnified party will, if a claim in respect thereof
is to be made against any indemnifying party under this Section 8, deliver to
the indemnifying party a written notice of the commencement thereof and the
indemnifying party shall have the right to participate in, and, to the extent
the indemnifying party so desires, jointly with any other indemnifying party
similarly noticed, to assume the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that the indemnified parties
shall have the right to retain one counsel of their own, with the fees and
expenses of one such counsel to be paid by the indemnifying party, if
representation of such indemnified parties by the counsel retained by the
indemnifying party would be inappropriate due to actual or potential differing
interests between such indemnified parties and any other party represented by
such counsel in such proceeding. The failure to deliver written notice to the
indemnifying party within a reasonable time of the commencement of any such
action shall not relieve such indemnifying party of any liability to the
indemnified party under this Section 8 except if, and only to the extent that,
the indemnifying party is actually prejudiced thereby; and such failure to
deliver written notice to the indemnifying party will not relieve it of any
liability that it may have to any indemnified party otherwise than under this
Section 8.

            (d) The obligations of the Company and Holders under this Section 8
shall survive the completion of any offering of Registrable Securities in a
registration statement under this Agreement, and otherwise.

            (e) Any indemnity agreements contained herein shall be in addition
to any other rights to indemnification or contribution which any indemnified
party may have pursuant to law or contract and shall remain operative and in
full force and effect regardless of any investigation made or omitted by or on
behalf of any indemnified party.

            (f) If for any reason the foregoing indemnity is unavailable, then
the indemnifying party shall contribute to the amount paid or payable by the
indemnified party as a result of such losses, claims, damages, liabilities or
expenses (i) in such proportion as is appropriate to reflect the relative
benefits received by the indemnifying party on the one hand and the indemnified
party on the other (taking into consideration, among other things, the fact that
the provision of the registration rights and indemnification hereunder is a
material inducement to the Investors to purchase Registrable Securities pursuant
to the Purchase Agreement) or (ii) if the


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allocation provided by clause (i) above is not permitted by applicable law or
provides a lesser sum to the indemnified party than the amount hereinafter
calculated, in such proportion as is appropriate to reflect not only the
relative benefits received by the indemnifying party on the one hand and the
indemnified party on the other (taking into consideration, among other things,
the fact that the provision of the registration rights and indemnification
hereunder is a material inducement to the Investors to purchase Registrable
Securities pursuant to the Purchase Agreement) but also the relative fault of
the indemnifying party and the indemnified party as well as any other relevant
equitable considerations. The relative fault shall be determined by reference
to, among other things, whether the untrue or alleged untrue statement of a
material fact or the omission or alleged omission to state a material fact
relates to information supplied by or on behalf of the indemnifying party or the
indemnified party and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such untrue statement or
omission. No Person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any Person who was not guilty of such fraudulent misrepresentation.
Notwithstanding anything to the contrary in this Section 8, no Holder shall be
required, pursuant to this Section 8, to contribute any amount in excess of the
net proceeds received by such indemnifying party from the sale of Common Stock
in the offering to which the losses, claims, damages, liabilities or expenses of
the indemnified party relate.

            9. Reports Under the Exchange Act. With a view to making available
to the Holders the benefits of Rule 144 under the Securities Act and any other
rule or regulation of the SEC that may at any time permit a Holder to sell
securities of the Company to the public without registration or pursuant to a
registration on Form S-3, the Company agrees to use commercially reasonable
efforts to:

            (a) make and keep public information available, as those terms are
understood and defined in Rule 144 under the Securities Act, at all times after
the effective date of the first registration statement filed by the Company for
the offering of its securities to the general public;

            (b) take such action as is necessary to enable the Holders to
utilize Form S-3 for the sale of their Registrable Securities;

            (c) file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and the Exchange Act;
and

            (d) furnish to any Holder, so long as the Holder owns any
Registrable Securities, forthwith upon request (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144 under
the Securities Act (at any time after the effective date of the first
registration statement filed by the Company) and the Securities Act and Exchange
Act (at any time after it has become subject to such reporting requirements) or
that it qualifies as a registrant whose securities may be resold pursuant to
Form S-3 (at any time it so qualifies), (ii) a copy of the most recent annual or
quarterly report of the Company and such other reports and documents so filed by
the Company, and (iii) such other information as may be reasonably requested in
availing any Holder of any rule or regulation of the SEC which permits the
selling of any such securities without registration or pursuant to such form.


                                     - 10 -
<PAGE>

            10. Rule 144A Information. During any period in which the Company is
not subject to Section 13 or 15(d) of the Exchange Act, the Company shall make
available information required to be provided by Rule 144A(d)(4), upon request.

            11. Assignment of Registration Rights. The rights to cause the
Company to register Registrable Securities pursuant to this Agreement may be
assigned in whole or in part by a Holder to one or more transferees or assignees
of not less than 1,000,000 shares of Registrable Securities; provided, however,
that (i) such transferee or assignee delivers to the Company a written
instrument by which such transferee or assignee agrees to be bound by the
obligations imposed on Holders under this Agreement to the same extent as if
such transferee or assignee was a party hereto; and (ii) such volume limitation
shall not apply to transferees or assignees who are Affiliates or the transferor
or assignor.

            12. Limitations on Registration Rights. Except as set forth in the
Amended Investor Rights Agreement dated as of July 30, 1999, as amended, the
Company represents and warrants to the Holders that no other "registration
rights" relating to securities of the Company exist on the date hereof. Except
as set forth in the Amended Investor Rights Agreement dated as of July 30, 1999,
as amended, each of the Holders represents to each other Holder that it has no
other "registration rights" relating to securities of the Company as of the date
hereof. From and after the date of this Agreement, the Company shall not,
without the prior written consent of the Holders of a majority of the
outstanding Registrable Securities, enter into any agreement with any holder or
prospective holder of any securities of the Company which would allow such
holder or prospective holder (a) to include such securities in any registration
filed under this Agreement, unless under the terms of such agreement, such
holder or prospective holder may include such securities in any such
registration only to the extent that the inclusion of such holder's securities
will not reduce the amount of the Registrable Securities of the Holders which is
included therein or (b) to request a registration. From and after the date of
this Agreement, the Company shall not, without the prior written consent of the
Holders of a majority of the Series C Stock, enter into any agreement with any
holder or prospective holder of any securities of the Company which would grant
such holder or prospective holder rights superior to those granted hereunder to
the Holders of the Series C Stock. It is understood and agreed that the
registration rights set forth herein apply only to the Common Shares and that
nothing contained herein shall obligate the Company to register any shares of
the Preferred Stock.

            13. "Market Stand-Off" Agreement. Each Holder hereby agrees that, if
requested by an underwriter in connection with an initial underwritten public
offering of the Company's Common Stock, during the period of 180 days following
the effective date of a registration statement of the Company filed under the
Securities Act in connection with such underwritten offering, it shall not, to
the extent requested by the Company and such underwriter, sell or otherwise
transfer or dispose of (other than to donees or partners who agree to be
similarly bound) any Common Stock or any securities of the Company convertible
into Common Stock held by it, except Common Stock included in such registration.
In addition, for a period of 180 days following the consummation of an initial
public offering and for such reasonable amount of time prior to such
consummation as the underwriters may request (collectively, the "Lock-up
Period"), the Company shall use commercially reasonable efforts to require that
during the Lock-Up Period its directors, officers and beneficial owners of five
percent (5%) or more of the Company's securities do not, sell or otherwise
transfer or dispose of (other than to donees or


                                     - 11 -
<PAGE>

partners who agree to be similarly bound) any Common Stock or any securities of
the Company convertible into Common Stock held by it, except Common Stock
included in such registration, without the express written consent of the
underwriters. Notwithstanding the foregoing, the provisions of this Section 13
shall not apply (i) to shares of Common Stock acquired by a Holder in the
Company's initial public offering of Common Stock pursuant to an effective
registration statement filed with the SEC or (ii) to shares of Common Stock
acquired by a Holder in the public market subsequent to the Company's initial
public offering of Common Stock pursuant to an effective registration statement
filed with the SEC.

            14. Amendment Waiver. Any provision of this Agreement may be amended
only with the written consent of the Company and the Holders of a majority of
the Registrable Securities then outstanding (including at least a majority in
interest of the Outside Investors and at least a majority in interest of the
Series C Stock and Common Stock obtained upon conversion thereof and that is
held by the Series C Investors); provided, however, that should an amendment
hereto be detrimental to the interests of the Series C Investors with respect to
their holdings of Series C Stock, such amendment shall required the written
consent of each Series C Investor. The observance of any provision of this
Agreement may be waived (either generally or in a particular instance and either
retroactively or prospectively) only with the written consent of the party to be
charged, provided that the Holders of a majority of the Registrable Securities
then outstanding (including at least a majority in interest of the Outside
Investors) may act on behalf of all such Holders of Registrable Securities. Any
amendment or waiver effected in accordance with this Section 14 shall be binding
upon each Holder of Registrable Securities at the time outstanding, each future
Holder of all such securities, and the Company.

            15. Changes in Registrable Securities. If, and as often as, there
are any changes in the Registrable Securities by way of stock split, stock
dividend, combination or reclassification, or through merger, consolidation,
reorganization or recapitalization, or by any other means, appropriate
adjustment shall be made in the provisions of this Agreement, as may be
required, so that the rights and privileges granted hereby shall continue with
respect to the Registrable Securities as so changed. Without limiting the
generality of the foregoing, the Company will require any successor by merger or
consolidation to assume and agree to be bound by the terms of this Agreement, as
a condition to any such merger or consolidation.

            16. Information. Each of the Outside Investors (and, in the case of
clauses (ii) and (iii) below, each of the Angel Investors) and each of their
respective assignees shall be entitled to receive, and the Company agrees to
provide to each of the Outside Investors (and, in the case of clauses (ii) and
(iii) below, each of the Angel Investors) and each of their respective
assignees, the following:

            (a) Financial and Related Data.

                  (i) As soon as available, but in any event not later than
thirty (30) days after the end of each month, the unaudited balance sheet as at
the end of such month of the Company and the related unaudited statements of
operations, stockholders' equity and cash flows for such month and for the
elapsed period in such fiscal year, all in reasonable detail and stating in
comparative form the figures as of the end of and for the comparable period of
the preceding fiscal year and budgeted figures for the period. All such
financial statements shall be complete


                                     - 12 -
<PAGE>

and correct in all material respects, and shall be accompanied by a certificate
of the President or chief financial officer of the Company to such effect.

                  (ii) As soon as available, but in any event not later than
forty-five (45) days after the end of each fiscal quarter, the unaudited balance
sheet as at the end of such quarter of the Company and the related unaudited
statements of operations, stockholders' equity and cash flows of such quarter
and for the elapsed period of such fiscal year, all in reasonable detail and
stating in comparative form the figures as of the end of and for the comparable
period of the preceding fiscal year and budgeted figures for the period. All
such financial statements shall be complete and correct in all material
respects, and shall be accompanied by a certificate of the President or chief
financial officer of the Company to such effect.

                  (iii) As soon as available, but in any event within ninety
(90) days after the end of each fiscal year of the Company, the audited balance
sheet of the Company as at the end of such fiscal year and the related audited
statements of operations, stockholders' equity and cash flows of the Company for
such fiscal year, all in reasonable detail and stating in comparative form the
figures as at the end of and for the previous fiscal year and budgeted figures
for the fiscal year, accompanied by an opinion of an accounting firm of
nationally recognized standing selected by the Company with respect to such
financial statements, which opinion shall state that such accounting firm's
audit was conducted in accordance with generally accepted auditing standards
and, accordingly, included such tests of accounting records and such other
auditing procedures as were considered necessary under the circumstances. All
such financial statements shall be complete and correct in all material respects
and prepared in reasonable detail and in accordance with GAAP applied, except as
stated therein, on a consistent basis throughout the periods reflected therein.

                  (iv) As soon as available, but in any event not later than
thirty (30) days prior to the end of each fiscal year of the Company, the
financial plan and business plan of the Company for the next succeeding fiscal
year, including but not limited to cash flow and balance sheet projections,
capital budget and operating budget, calculated monthly, and any updates or
revisions as soon as available.

                  (v) Promptly after receipt, copies of all management letters
from accountants and all certificates prepared by or for the Company as to
compliance, defaults, material adverse changes, material litigation or similar
matters, but only to the extent that the delivery thereof would not result in
the loss of any generally recognizable privilege otherwise applicable thereto.

                  (vi) Within fifteen (15) days after the Company obtains
knowledge of the commencement or written threat of commencement of any material
litigation or proceeding against the Company or its assets, written notice by
the Company of the nature and extent of such litigation or proceeding.

                  (vii) Promptly, but in any event within five (5) days, after
any distribution to its stockholders generally or to specific stockholders by
agreement, to its directors, to prospective investors or to the financial
community of an annual report, proxy statement, registration statement or other
similar report or communication, a copy of each such report, proxy


                                     - 13 -
<PAGE>

statement, registration statement or other similar report or communication; and
promptly, but in any event within ten (10) days after any filing with the SEC or
with any national securities exchange or with the National Association of
Securities Dealers, Inc., of any publicly available annual or periodic or
special report or proxy statement or registration statement, a copy of such
report or statement; and promptly, but in any event within two (2) business
days, after released, copies of all press releases and other statements made
available generally by the Company to the public concerning material
developments.

                  (viii) Within sixty (60) days after the end of each fiscal
year, a list of stockholders and other security holders, showing the authorized
and outstanding shares by class (including the common stock equivalents of any
convertible security), the holdings of each stockholder (both before giving
effect to dilution and on a fully-diluted basis) and the holdings of each Person
that holds options, warrants or convertible securities (both before giving
effect to dilution and on a fully diluted basis).

                  (ix) From time to time, and promptly, such additional
information and financial data regarding results of operations, financial
condition, business, affairs or prospects of the Company, which any Investor may
reasonably request.

The obligation of the Company to provide the items required by clauses (v), (vi)
and (viii) shall terminate upon the consummation of an underwritten public
offering by the Company under the Securities Act. Provided that the Company is a
reporting company under the Exchange Act, the obligation of the Company to
provide the items required by the remaining clauses of this Section 14(a) shall
terminate as to any Investor in the event such Investor (1) holds less than 3%
of the outstanding capital stock of the Company (calculated on an as-converted
to common stock basis) or (2) elects by written notice to the Company to
terminate such obligation.

            (b) Access to Properties. The Company shall permit representatives
designated by each Outside Investor, upon reasonable prior notice to the
Company, to visit and inspect each of the Company's properties, to examine its
respective corporate and financial records (and make copies thereof or extracts
therefrom), to discuss its respective affairs, finances and accounts with the
Company's directors and officers, and, through the President or chief financial
officer of the Company, as the case may be, its key employees and accountants,
all at such reasonable times as may be requested by any such Investor.

            17. Termination of Registration Rights. The registration rights of
any Holder provided herein shall terminate if in the written opinion of counsel
for the Company, which counsel and the opinion so rendered shall be reasonably
acceptable to such Holder of Registrable Securities, such Holder may sell
without registration under the Securities Act all Registrable Securities then
held by such Holder under Rule 144 of the Securities Act without regard to
volume limitations.

            18. Legends and Opinions. The Company shall not require an opinion
of counsel for the Holders before (i) authorizing the transfer of shares of
Registrable Securities (A) pursuant to an effective registration statement or
Rule 144 of the Securities Act or (B) in connection with any distributions to
any partner of a Holder or (ii) the removal of securities legends for the
certificates representing such Registrable Securities; provided, however, that
in


                                     - 14 -
<PAGE>

the case of clause (ii), such Holder shall certify to the Company that such
Holder is permitted to sell such Registrable Securities pursuant to Rule 144(k)
of the Securities Act. The foregoing shall not imply that an opinion of counsel
to the Company shall not be required in such circumstances.

            19. Entire Agreement. Each of the Investor Rights Agreement, dated
March 29, 1999, by and among the Company and the parties set forth on the
signature pages thereto, and the Amended and Restated Investor Rights Agreement,
dated as of July 29, 1999, by and among the Company and the parties set forth on
the signature pages thereto, are hereby terminated and each shall be of no
further force or effect. This Agreement constitutes the full and entire
understanding and agreement among the parties with regard to the subject matter
hereof. Nothing in this Agreement, express or implied, is intended to confer
upon any Person, other than the parties hereto and their respective successors
and assigns, any rights, remedies, obligations, or liabilities under or by
reason of this Agreement, except as expressly provided herein.

            20. Governing Law. This Agreement shall be governed in all respects
by the laws of the State of Delaware, exclusive of reference to rules and
principles of conflicts of law.

            21. Successors and Assigns. The provisions hereof shall inure to the
benefit of, and be binding upon, the successors, permitted assigns (as provided
in Section 11), heirs, executors and administrators of the parties hereto;
provided, however, that except as provided in Section 11, this Agreement may
only be assigned in connection with an estate transfer or as otherwise approved
in writing by the directors elected solely by the holders of the Preferred
Stock.

            22. Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon receipt by the party to be notified or three (3) days
after deposit with the United States Post Office, by registered or certified
mail, postage prepaid and addressed to the party to be notified (a) if to a
party other than the Company, at such party's address set forth at the end of
this Agreement or at such other address as such party shall have furnished the
Company in writing, or, until any such party so furnishes an address to the
Company, then to and at the address of the last holder of the shares covered by
this Agreement who has so furnished an address to the Company, or (b) if to the
Company, at its address set forth at the end of this Agreement, or at such other
address as the Company shall have furnished to the parties in writing.

            23. Severability. Any invalidity, illegality or limitation on the
enforceability of this Agreement or any part thereof, by any party whether
arising by reason of the law of the respective party's domicile or otherwise,
shall in no way affect or impair the validity, legality or enforceability of
this Agreement with respect to other parties. If any provision of this Agreement
shall be judicially determined to be invalid, illegal or unenforceable, the
validity, legality and enforceability of the remaining provisions shall not in
any way be affected or impaired thereby.

            24. Titles and Subtitles. The titles of the Sections of this
Agreement are for convenience of reference only and are not to be considered in
construing this Agreement.

            25. Delays or Omissions: Remedies Cumulative. It is agreed that no
delay or omission to exercise any right, power or remedy accruing to the
parties, upon any breach or


                                     - 15 -
<PAGE>

default of the Company under this Agreement, shall impair any such right, power
or remedy, nor shall it be construed to be a waiver of any such breach or
default, or any acquiescence therein, or of any similar breach or default
thereafter occurring; nor shall any waiver of any single breach or default be
deemed a waiver of any other breach or default theretofore or thereafter
occurring. It is further agreed that any waiver, permit, consent or approval of
any kind or character by a party of any breach or default under this Agreement,
or any waiver by a party of any provisions or conditions of this Agreement must
be in writing and shall be effective only to the extent specifically set forth
in writing and that all remedies, either under this Agreement, or by law or
otherwise afforded to a party, shall be cumulative and not alternative.

            26. Arbitration. Any controversy or claim arising out of or in
conjunction with this Agreement (other than an action for injunctive relief)
shall be settled by arbitration in accordance with the rules of the American
Arbitration Association then in effect in the State of Delaware and judgment
upon such award rendered by the arbitrator shall be final and binding upon the
parties and may be entered and enforced in any court having jurisdiction
thereof. The arbitration shall be held in the State of Delaware. The arbitration
award shall include attorneys' fees and costs to the prevailing party.

            27. Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

            28. Accession to Agreement. Any person or entity who becomes a party
to the Purchase Agreement as an Additional Investor (as defined therein) shall
become a party to this Agreement by executing a counterpart signature page
hereto, whereupon such person shall become a party to this Agreement for all
purposes hereunder as if such person had been an original signatory.

            29. Aggregation. For purposes of determining the rights exercisable
by a Holder hereunder, all shares of Registrable Securities held by a Series C
Investor and that constitute either Series C Stock or Common Stock obtained upon
the conversion of Series C Stock may be aggregated by the Holder with those
shares of Registrable Securities constituting Series C Stock or Common Stock
obtained upon conversion of Series C Stock beneficially held by Affiliates of
such Holder. For purposes hereof, "Affiliate" shall mean with respect to any
Holder that is a corporation, partnership or other business entity, any of the
stockholders, subsidiaries, officers, directors, members or partners of such
Holder, and any other corporation, partnership or other business entity which
directly or indirectly controls, is controlled by or is under common control
with such Holder. For purposes hereof, the following entities shall be deemed to
be Affiliates of each other: Amerindo Technology Growth Fund II; Matthew
Fitzmaurice; Litton Master Trust; Emeric McDonald; William S. Slattery; James
Stableford; Vertex Capital II, LLC; Sand Brothers Venture Capital LLC; and SB
Necessary Associates LLC. For purposes hereof, the following entities shall be
deemed to be Affiliates of each other: BayStar Capital L.P., BayStar
International Ltd., Wolstar BV and Stichting Wolstar Administratiekantoor.

                                    * * * * *


                                     - 16 -
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have executed this Agreement
as of the day and year first above written.

                                                      Address

ESSENTIAL.COM, INC.                        Three Burlington Woods Drive
                                           Burlington, Massachusetts 01803-4543
By: /s/ Akhil Garland                      Attention:  Akhil Garland, President
    -----------------------                Telephone:  (781) 932-0088
    Name:  Akhil Garland                   Telecopier: (781) 932-6611
    Title: President


                                     - 17 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ [ILLEGIBLE]
                                    -----------------------------------------
                                    Signature of Investor


                                    Amerindo Technology Growth Fund II
                                    -----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Rachel E. Hyman, Manager
                                    -----------------------------------------
                                    Signature of Investor


                                    Aurora Technology Fund LLC
                                    by Aurora Technology Fund Management LLC
                                    by Rachel E. Hyman
                                    -----------------------------------------
                                    Printed Name of Investor


                                             152 W. 57th St., 57th Floor
                                    Address: New York, NY 10019
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Gregory Bellow
                                    -----------------------------------------
                                    Signature of Investor


                                    Bellow 1984 Trust u/a 11/20/84
                                    By: Gregory Bellow
                                    -----------------------------------------
                                    Printed Name of Investor


                                             775 Hillcrest Way
                                    Address: Redwood City, CA 94062
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Michael A. Roth
                                    -----------------------------------------
                                    Signature of Investor


                                    BayStar Capital. L.P.
                                    -----------------------------------------
                                    Printed Name of Investor


                                             1500 W. Market St.
                                             Suite 200
                                    Address: Mequon, WI 53092
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Michael A. Roth
                                    -----------------------------------------
                                    Signature of Investor


                                    BayStar International Ltd.
                                    -----------------------------------------
                                    Printed Name of Investor


                                             1500 W. Market St.
                                             Suite 200
                                    Address: Mequon, WI 53092
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Robert H. Buescher
                                    -----------------------------------------
                                    Signature of Investor


                                    Bessec Ventures IV LP
                                    By: Deer IV & Co. LLC, General Partner
                                    By: Robert H. Buescher. Manager
                                    -----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Robert H. Buescher
                                    -----------------------------------------
                                    Signature of Investor


                                    BESSEMER VENTURE PARTNERS IV. L.P.
                                    By: Deer IV & Co. LLC, General Partner
                                    By: Robert H. Buescher, Manager
                                    -----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                  INVESTOR:


                                  BRAND EQUITY VENTURES I, L.P.
                                  /s/ William Meurer
                                  ----------------------------------------------
                                  Signature of Investor


                                  By: William Meurer, Vice President, Brand
                                  Equity Partners I, L.L.C., its General Partner
                                  ----------------------------------------------
                                  Printed Name of Investor


                                  Address:
                                           -------------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Manuel Harrington
                                    -----------------------------------------
                                    Signature of Investor


                                    COMDISCO, INC.
                                    Manuel A. Harrington
                                    -----------------------------------------
                                    Printed Name of Investor


                                             611 North River Road
                                             Rosemont, IL 60018
                                    Address: Attn: Venture Group
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Hussain Sajwani
                                    -----------------------------------------
                                    Signature of Investor


                                    DAMAC INVESTORS XII INC.
                                    Hussain Sajwani -- Director
                                    -----------------------------------------
                                    Printed Name of Investor


                                             Post Box: 2195
                                    Address: Dubai, UAE
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                 INVESTOR:


                                 /s/ Hussain Sajwani
                                 -----------------------------------------------
                                 Signature of Investor


                                 DAMAC TECHNOLOGY PARTNERS, LP
                                 Hussain Sajwani -- Director of General Partner
                                 -----------------------------------------------
                                 Printed Name of Investor


                                          Post Box: 2195
                                 Address: Dubai, UAE
                                          -----------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Linda DeRenzo
                                    -----------------------------------------
                                    Signature of Investor


                                    Linda DeRenzo
                                    -----------------------------------------
                                    Printed Name of Investor


                                             238 Kenrick Street
                                    Address: Newton, MA 02458
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Ivy Dodes
                                    -----------------------------------------
                                    Signature of Investor


                                    DLJ ESC II, L.P.
                                    By: DLJ LBO Plans Management Corporation
                                    By: Ivy Dodes, Vice President
                                    -----------------------------------------
                                    Printed Name of Investor


                                             277 Park Avenue, 23rd Floor
                                    Address: New York, NY 10172
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Ivy Dodes
                                    -----------------------------------------
                                    Signature of Investor


                                    DLJ FUND INVESTMENT PARTNERS II, L.P.
                                    By: DLJ LBO Plans Management Corporation
                                    By: Ivy Dodes, Vice President
                                    -----------------------------------------
                                    Printed Name of Investor


                                             277 Park Avenue, 23rd Floor
                                    Address: New York, NY 10172
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Ivy Dodes
                                    -----------------------------------------
                                    Signature of Investor


                                    DLJ Private Equity Employees Fund, L.P.
                                    By: DLJ LBO Plans Management Corporation
                                    By: Ivy Dodes, Vice President
                                    -----------------------------------------
                                    Printed Name of Investor


                                             277 Park Avenue, 23rd Floor
                                    Address: New York, NY 10172
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

       The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Ivy Dodes
                                    -----------------------------------------
                                    Signature of Investor


                                    DLJ Private Equity Partners Fund, L.P.
                                    By: WSW Capital, Inc.
                                    By: Ivy Dodes, Vice President
                                    -----------------------------------------
                                    Printed Name of Investor


                                             277 Park Avenue, 23rd Floor
                                    Address: New York, NY 10172
                                             --------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                              INVESTOR:


                              /s/ Scott B. Ungerer
                              --------------------------------------------------
                              Signature of Investor


                              EnerTech Capital Partners, L.P.
                              By: EnerTech Management, L.P., its General Partner
                              By: EnerTech Management Company, L.L.C.,
                                   its General Partner
                              --------------------------------------------------
                              Printed Name of Investor


                              Address:
                                       -------------------------------------


                                     - 18 -
<PAGE>

             SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                              INVESTOR:


                              /s/ Scott B. Ungerer
                              --------------------------------------------------
                              Signature of Investor


                              EnerTech Capital Partners II, L.P.
                              By: ECP II Management, L.P., its General Partner
                              By: ECP II Management, L.L.C., its General Partner
                              --------------------------------------------------
                              Printed Name of Investor


                              Address:
                                       -------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Matthew O. Fitzmaurice
                                    ----------------------------------------
                                    Signature of Investor


                                    Matthew O. Fitzmaurice
                                    ----------------------------------------
                                    Printed Name of Investor


                                             130 West Lake Street
                                    Address: Wayzata, MN 55391
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Marie Paulette Galliker
                                    ----------------------------------------
                                    Signature of Investor


                                    Marie Paulette Galliker
                                    ----------------------------------------
                                    Printed Name of Investor


                                             14 Ship Pasture Way
                                    Address: E. Sandwich, MA 02537
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Thomas C. O'Laughlin
                                    ----------------------------------------
                                    Signature of Investor


                                    Gas Research Institute
                                    ----------------------------------------
                                    Printed Name of Investor


                                             8600 West Bryn Mawr Avenue
                                    Address: Chicago, IL 60631
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                   INVESTOR:


                                   /s/ Eric J. Hall
                                   ---------------------------------------------
                                   Signature of Investor


                                   Robert Hall, Eric Hall & William Hall, JTWROS
                                   ---------------------------------------------
                                   Printed Name of Investor


                                            183 State Street
                                   Address: Boston, MA 02109
                                            ------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                   INVESTOR:


                                   /s/ Robert A. Hall
                                   ---------------------------------------------
                                   Signature of Investor


                                   Robert Hall, Eric Hall & William Hall, JTWROS
                                   ---------------------------------------------
                                   Printed Name of Investor


                                            183 State Street
                                   Address: Boston, MA 02109
                                            ------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                   INVESTOR:


                                   /s/ William J. Hall
                                   ---------------------------------------------
                                   Signature of Investor


                                   Robert Hall, Eric Hall & William Hall, JTWROS
                                   ---------------------------------------------
                                   Printed Name of Investor


                                            183 State Street
                                   Address: Boston, MA 02109
                                            ------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ George W. Thibeault
                                    ----------------------------------------
                                    Signature of Investor


                                    HIGH STREET INVESTORS 2000
                                    By: Testa, Hurwitz & Thibeault, LLP
                                    By: George W. Thibeault, Partner
                                    ----------------------------------------
                                    Printed Name of Investor


                                             125 High Street
                                    Address: Boston, MA 02110
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Michael B. Kolowich
                                    ----------------------------------------
                                    Signature of Investor


                                    Michael E. Kolowich
                                    ----------------------------------------
                                    Printed Name of Investor


                                             116 Monument Street
                                    Address: Concord, MA 01742
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Edmund W. Lang
                                    ----------------------------------------
                                    Signature of Investor


                                    Edmund W. Lang
                                    ----------------------------------------
                                    Printed Name of Investor


                                             5 Tabor Hill Road
                                    Address: Lincoln, MA 01773
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Ilene H. Lang
                                    ----------------------------------------
                                    Signature of Investor


                                    Ilene H. Lang
                                    ----------------------------------------
                                    Printed Name of Investor


                                             78 Jason Street
                                    Address: Arlington, MA 02476
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:

                                    [ILLEGIBLE]
                                    ----------------------------------------
                                    Signature of Investor


                                    Litton Master Trust
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                            --------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Emeric J. McDonald
                                    ----------------------------------------
                                    Signature of Investor


                                    Emeric J. McDonald
                                    ----------------------------------------
                                    Printed Name of Investor


                                             707 Continental Circle, #431
                                    Address: Mt. View, CA 94040
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Robert W. Driscoll, Jr.
                                    ----------------------------------------
                                    Signature of Investor


                                    Mellon Ventures II, L.P.
                                    By MVMA II, L.P., its General Partner
                                    By MVMA, Inc. its General Partner
                                    ----------------------------------------
                                    Printed Name of Investor


                                             Mellon Ventures, Inc.
                                             Five Radnor Corporate Center
                                             100 Matsonford Road, Suite 170
                                    Address: Radner, PA 19087
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Norman C. Nicholson
                                    ----------------------------------------
                                    Signature of Investor


                                    Norman C. Nicholson
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/[ILLEGIBLE], EVP & CFO
                                    ----------------------------------------
                                    Signature of Investor


                                    Rare Medium Group, Inc.
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Pamela Stone Ryan
                                    ----------------------------------------
                                    Signature of Investor


                                    Pamela Stone Ryan
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Martin Sands
                                    ----------------------------------------
                                    Signature of Investor


                                    Sands Brothers Venture Capital LLC
                                    By: SB Venture Capital Management LLC
                                    By: Martin Sands, Manager
                                    ----------------------------------------
                                    Printed Name of Investor


                                             c/o Sands Brothers
                                             90 Park Avenue, 39th Floor
                                    Address: New York, New York 10016
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Martin Sands
                                    ----------------------------------------
                                    Signature of Investor


                                    SB Necessary Associates LLC
                                    By: SB Necessary Management Associates LLC
                                    By: Martin Sands, Manager
                                    ----------------------------------------
                                    Printed Name of Investor


                                             c/o Sands Brothers
                                             90 Park Avenue, 39th Floor
                                    Address: New York, New York 10016
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Abdullah Mosa'ad Abdulaziz
                                    ----------------------------------------
                                    Signature of Investor


                                    Saudi Paper Manufacturing Company, Ltd.
                                    Abdullah Mosa'ad Abdulaziz, Chairman
                                    ----------------------------------------
                                    Printed Name of Investor


                                             P.O. Box 55375
                                    Address: Riyadh 11534, K.S.A
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ William S. Slattery
                                    ----------------------------------------
                                    Signature of Investor


                                    William S. Slattery
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ James Stableford
                                    ----------------------------------------
                                    Signature of Investor


                                    James Stableford
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ William A. Stone
                                    ----------------------------------------
                                    Signature of Investor


                                    William A. Stone
                                    ----------------------------------------
                                    Printed Name of Investor


                                             5208 Indian Woods Ct.
                                    Address: Louisville, KY 40207
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ James W. Storey
                                    ----------------------------------------
                                    Signature of Investor


                                    James W. Storey
                                    ----------------------------------------
                                    Printed Name of Investor


                                    Address:
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Scott D. Sullivan
                                    ----------------------------------------
                                    Signature of Investor


                                    Scott D. Sullivan
                                    ----------------------------------------
                                    Printed Name of Investor


                                             6318 Woodbury Road
                                    Address: Boca Raton, FL 33433
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Brad Rudderman
                                    ----------------------------------------
                                    Signature of Investor


                                    Talon Ventures Two, LLC
                                    ----------------------------------------
                                    Printed Name of Investor


                                             9440 Santa Monica Blvd, #600
                                    Address: Beverly Hills, CA 90210
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Matthew O. Fitzmaurice
                                    ----------------------------------------
                                    Signature of Investor


                                    Vertex Capital II, L.L.C.
                                    By: Matthew O. Fitzmaurice, Manager
                                    ----------------------------------------
                                    Printed Name of Investor


                                             Attn: Matthew O. Fitzmaurice
                                             130 West Lake Street
                                    Address: Wayzata, MN 55391
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Brooks Whitehouse, Jr.
                                    ----------------------------------------
                                    Signature of Investor


                                    Brooks Whitehouse, Jr.
                                    ----------------------------------------
                                    Printed Name of Investor


                                             74 Gates Street
                                    Address: Portsmouth, NH 03801
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Maurice Wyatt
                                    ----------------------------------------
                                    Signature of Investor


                                    Maurice Wyatt
                                    ----------------------------------------
                                    Printed Name of Investor


                                             7 Bertwell Ct.
                                    Address: Timonium, MD 21093
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Henry M. Zachs
                                    ----------------------------------------
                                    Signature of Investor


                                    Henry M. Zachs
                                    ----------------------------------------
                                    Printed Name of Investor


                                             40 Woodland Street
                                    Address: Hartford, CT 06105
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Henry M. Zachs
                                    ----------------------------------------
                                    Signature of Investor


                                    Zafa II LLC
                                    Henry M. Zachs
                                    ----------------------------------------
                                    Printed Name of Investor


                                             40 Woodland Street
                                    Address: Hartford, CT 06105
                                             -------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                    INVESTOR:


                                    /s/ Kevin Cannon
                                    ------------------------------------------
                                    Signature of Investor


                                    Kevin Cannon, CEO Zweig-Dimenna
                                    International, Managers, Inc., Investment
                                    Manager of Zweia-Dimenna International Ltd
                                    ------------------------------------------
                                    Printed Name of Investor


                                             Zweig-Dimenna International Ltd
                                             c/o Zwieg-Dimenna International
                                                 Managers, Inc.
                                             900 Third Avenue
                                    Address: New York, New York 10022
                                             ---------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                 INVESTOR:


                                 /s/ Kevin Cannon
                                 -----------------------------------------------
                                 Signature of Investor


                                 Kevin Cannon, CEO, Zweig-Dimenna Assoc. LLC
                                 General Partner of Zweig-Dimenna Investors, L.P
                                 -----------------------------------------------
                                 Printed Name of Investor


                                          Zweig-Dimenna Investors, L.P.
                                          900 Third Avenue
                                 Address: New York, New York 10022
                                          --------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                 INVESTOR:


                                 /s/ Kevin Cannon
                                 -----------------------------------------------
                                 Signature of Investor


                                 Kevin Cannon, CEO, Zweig-Dimenna Assoc. LLC
                                 General Partner of Zweig-Dimenna Partners, L.P.
                                 -----------------------------------------------
                                 Printed Name of Investor


                                          Zweig-Dimenna Partners, L.P.
                                          900 Third Avenue
                                 Address: New York, NY 10022
                                          --------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                                   INVESTOR:


                                   /s/ Kevin Cannon
                                   ---------------------------------------------
                                   Signature of Investor


                                   Kevin Cannon, CEO, Zweig-Dimenna Assoc. LLC
                                   General Partner of Zweig-Dimenna Select, L.P.
                                   ---------------------------------------------
                                   Printed Name of Investor


                                            Zweig-Dimenna Select, L.P.
                                            900 Third Avenue
                                   Address: New York, NY 10022
                                            ------------------------------------


                                     - 18 -
<PAGE>

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                                 SIGNATURE PAGE

      The undersigned hereby (a) executes that certain Second Amended and
Restated Investor Rights Agreement dated as of the date first above written (the
"Investor Rights Agreement") by and among essential.com, inc. and the Investors
named in Schedule I thereto, (b) agrees to become a party to and be bound as an
"Investor" under such Investor Rights Agreement, and (c) authorizes this
signature page to be attached as a counterpart signature page to such Investor
Rights Agreement.

                               INVESTOR:


                               /s/ Kevin Cannon
                               -------------------------------------------------
                               Signature of Investor


                               Kevin Cannon, CEO, Zweig-Dimenna Assoc. LLC
                               General Partner of
                               Zweig-Dimenna Special Opportunities, L.P.
                               -------------------------------------------------
                               Printed Name of Investor


                                        Zweig-Dimenna Special Opportunities, L.P
                                        900 Third Avenue
                               Address: New York, NY 10022
                                        ----------------------------------------


                                     - 18 -
<PAGE>

                                   SCHEDULE I

Angel Investors

Bellow 1984 Trust u/a 11/20/84
Linda DeRenzo
Marie Paulette Galliker
Robert A. Hall, Eric J. Hall & William J. Hall, JTWROS
Michael E. Kolowich
Edmund W. Lang
Ilene H. Lang
David J. Mushlitz
Mark C. Nicholson
Norman C. Nicholson, Jr.
Pamela Stone Ryan
William A. Stone
James W. Storey
Brooks Whitehouse, Jr.
Maurice R. Wyatt, Sr.
Henry Zachs

Existing Outside Investors

EnerTech Capital Partners, L.P.
Bessemer Venture Partners IV L.P.
Bessec Venture Partners IV L.P.
Brand Equity Ventures I, L.P.
Comdisco, Inc.
Gas Research Institute
Zafa II, LLC

Series C Investors

Amerindo Technology Growth Fund II
Aurora Technology Fund II LLC
BayStar Capital L.P.
Bessec Ventures IV L.P.
Bessemer Venture Partners IV L.P.
Brand Equity Ventures I, L.P.
Comdisco, Inc.
Damac Investors XII Inc.
Damac Technology Partners, L.P.
DLJ ESC II, L.P.


                                     - 19 -
<PAGE>

DLJ Investment Partners II, L.P.
DLJ Private Equity Employees Fund, L.P.
DLJ Private Equity Partners Fund, L.P.
EnerTech Capital Partners II, L.P.
Matthew Fitzmaurice
High Street Investors
Litton Master Trust
Emeric McDonald
Mellon Ventures II, L.P.
Rare Medium Group Inc.
Sands Brothers Venture Capital LLC
Saudi Paper Manufacturing Company Ltd.
SB Necessary Associates LLC
William Slattery
James Stableford
Scott Sullivan
Talon Ventures Two, LLC
Vertex Capital II, LLC
Zweig-Dimenna International Ltd.
Zweig-Dimenna Investors, L.P.
Zweig-Dimenna Partners, L.P.
Zweig-Dimenna Select, L.P.
Zweig-Dimenna Special Opportunities, L.P.


                                     - 20 -
<PAGE>

                                   SCHEDULE II

                               essential.com, inc.

              SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

                             INSTRUMENT OF ACCESSION

      The undersigned, __________________, as a condition precedent to becoming
the owner or holder of record of _____________________ (_______) shares of the
Series C Convertible Preferred Stock, par value $.01 per share, of
essential.com, inc., a Delaware corporation (the "Company"), hereby agrees to
become party to and bound by that certain Second Amended and Restated Investor
Rights Agreement, dated as of February 8, 2000, by and among the Company and
other stockholders of the Company as a Series C Investor. This Instrument of
Accession shall take effect and shall become an integral part of the said
Investor Rights Agreement immediately upon execution and delivery to the Company
of this Instrument.

      IN WITNESS WHEREOF, this INSTRUMENT OF ACCESSION has been duly executed by
or on behalf of the undersigned, as a sealed instrument under the laws of the
State of Delaware, as of the date below written.


                              Name:___________________________________

                              By:____________________________
                                 Name of Signator:
                                 Title (If Applicable):

                              Address:
                              ________________________________________
                              ________________________________________
                              ________________________________________

                              Date: __________________________________

                              Accepted:

                              essential.com, inc.

                              By:_____________________________________
                                Name:_________________________________
                                Title:________________________________

                              Date:___________________________________