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                                                                     Exhibit 4.2



                          REGISTRATION RIGHTS AGREEMENT

         THIS REGISTRATION RIGHTS AGREEMENT is entered into as of August 26,
2004, by and between Silicon Valley Bank ("Purchaser") and Evergreen Solar,
Inc., a Delaware corporation (the "Company").

                                    RECITALS

         A.       Concurrently with the execution of this Agreement, Purchaser
is acquiring from the Company a Warrant to Purchase Stock (the "Warrant")
pursuant to which Purchaser has rights to acquire from the Company the Shares
(as defined in the Warrant).

         B.       By this Agreement, Purchaser and the Company desire to set
forth the registration rights of the Shares.

         NOW, THEREFORE, in consideration of the premises and the mutual
promises, covenants and conditions hereinafter set forth, the parties hereto
mutually agree as follows:

         1        REGISTRATION RIGHTS. The company covenants and agrees as
follows:

         1.1      Definitions. For purposes of this Section 1:

                  (a)      The term "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 of 1933, as
amended, and the rules and regulations thereunder (the "Securities Act"), and
the declaration or ordering of effectiveness of such registration statement or
document;

                  (b)      The term "Registrable Securities" means (i) the
Shares, and (ii) any shares of the Company's common stock, $0.01 par value per
share ("Common Stock") or other securities of the Company 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, the Shares.

                  (c)      The terms "Holder" or "Holders" means Purchaser and
its qualifying transferees under subsection 1.8 hereof who hold Registrable
Securities.

                  (d)      The term "SEC" means the Securities and Exchange
Commission.

                  (e)      The terms "Form S-1," "Form S-3" etc. shall mean
those forms with such designations as are required by the SEC and any successor
or replacement forms adopted by the SEC.

         1.2      Company Registration.

                  (a)      Registration. If at any time or from time to time,
the Company shall determine to register any of its securities, for its own
account or the account of any of its shareholders, other than a registration (i)
on Form S-8 relating solely to employee stock option or purchase plans, (ii) on
Form S-4 relating solely to an SEC Rule 145 transaction, (iii) effected pursuant
to Section 8(c) of that certain Series D Preferred Stock Purchase Agreement by
and among the Company and the other parties thereto dated as


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of December 28, 1999 (the "Series D Agreement"), or (iv) in which any party
holding registration rights pursuant to the Series D Agreement has exercised its
or his right to include any Registrable Shares (as such term is defined in the
Series D Agreement) held by such party in such registration, the Company will:

                           (i)    promptly give to each Holder written notice
                  thereof (which shall include a list of the jurisdictions in
                  which the Company intends to attempt to qualify such
                  securities under the applicable blue sky or other state
                  securities laws); and

                           (ii)   include in such registration (and
                  qualifications), and in any underwriting involved therein, all
                  the Registrable Securities specified in a written request or
                  requests, made within 30 days after receipt of such written
                  notice from the Company, by any Holder or Holders, except as
                  set forth in subsection 1.2(c) below.

                  (b)      Underwriting. If the registration of which the
Company gives notice is for a registered public offering involving a
firm-commitment underwriting, the Company shall so advise the Holders as a part
of the written notice given pursuant to subsection 1.2(a)(i). In such event the
right of any Holder to registration pursuant to this subsection 1.2 shall be
conditioned upon such Holder's participation in such underwriting and the
inclusion of such Holder's Registrable Securities in the underwriting to the
extent provided herein. All Holders proposing to distribute their securities
through such underwriting shall (together with the Company and the other
shareholders distributing their securities through such underwriting) enter into
an underwriting agreement in customary form (and not inconsistent with the terms
hereof) with the underwriter or underwriters selected for such underwriting by
the Company.

                  (c)      In the case of any registration of Common Stock by
the Company in a firm-commitment underwriting, if the managing underwriters give
written advice to the Company that marketing factors require a limitation on the
number of shares of Common Stock (or other securities convertible into or
exercisable or exchangeable for Common Stock) to be offered and sold by
stockholders of Company in such offering, there shall be included in the
offering: (i) first, all shares of Common Stock proposed by Company to be sold
for its account; (ii) second, all shares of Common Stock requested by
stockholders of the Company to be included in such registration, which
stockholders have contractual registration rights from the Company on and as of
the date hereof; and (iii) that number of shares of Common Stock, if any,
requested to be included in such registration statement by Holders and by other
stockholders of the Company granted contractual registration rights from the
Company after the date hereof, on a pro rata basis based upon the number of
shares of Common Stock each Holder and each such other stockholder beneficially
owns.

         1.3      Expenses of Registration. All expenses incurred in connection
with any registration, qualification or compliance pursuant to this Section 1
including without limitation, all registration, filing and qualification fees,
printing expenses, underwriting fees, discounts and commissions(other than
underwriting fees, discounts and commissions in respect of Registrable
Securities included in such registration), fees and disbursements of counsel for
the Company and expenses of any special audits incidental to or required by such
registration, shall be borne by the Company. All expenses of any registered
offering not otherwise borne by the Company will be borne pro rata among the
Holders, any other shareholders of the Company participating in such offering
and the Company.


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         1.4      Registration Procedures. In the case of each registration,
qualification or compliance effected by the Company pursuant to this
Registration Rights Agreement, the Company will keep each Holder participating
therein advised in writing as to the initiation of each registration,
qualification and compliance and as to the completion thereof. At its expense
the Company will:

                  (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 registered
thereunder, keep such registration statement effective for up to 120 days (the
"Effective Period").

                  (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 numbers of copies of a
prospectus, including a preliminary prospectus, in conformity with the
requirements of the Securities Act, and such other documents as they may
reasonably request in order to facilitate the disposition of Registrable
Securities owned by them.

                  (d)      Use its best efforts to register and qualify the
securities covered by such registration statement under such other securities or
Blue Sky laws of such 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 to qualify to do business or to file a general consent
to service of process in any such states or jurisdictions.

                  (e)      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. Each Holder
participating in such underwriting shall also enter into and perform its
obligations under such an agreement provided that all other shareholders of the
Company participating in such offering do the same.

                  (f)      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.

         1.5      Indemnification.

                  (a)      The Company will indemnify each Holder of Registrable
Securities and each of its officers, directors and partners, and each person
controlling such Holder within the meaning of Section 15 of the Securities Act
("controlling person"), and each underwriter, if any, and each controlling
person of such underwriter, with respect to which registration, qualification or
compliance of Registrable Securities has been effected pursuant to this
Registration Rights Agreement, against all claims, losses, expenses, damages and
liabilities (or actions in respect thereto) arising out of or based on any
untrue statement (or alleged untrue statement) of a material fact contained in
any prospectus, offering circular or



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other document (including any related registration statement, notification or
the like) incident to any such registration, qualification or compliance, or
based on any omission (or alleged omission) to state therein a material fact
required to be stated therein or necessary to make the statement therein not
misleading, or any violation or alleged violation by the Company of the
Securities Act, the Securities Exchange Act of 1934, as amended, and the rules
and regulations thereunder ("Exchange Act") or any state securities law
applicable to the Company or any rule or regulation promulgated any such state
law and relating to action or inaction required of the Company in connection
with any such registration, qualification or compliance, and will reimburse each
such Holder, each of its officers, directors and partners, and each person
controlling such Holder, each such underwriter and each person who controls any
such underwriter, within a reasonable amount of time after incurred for any
reasonable legal and any other expenses incurred in connection with
investigating, defending or settling any such claim, loss, damage, liability or
action; provided, however, that the indemnity agreement contained in this
subsection 1.5(a) shall not apply to amounts paid in settlement of any such
claim, loss, damage, liability, or action if such settlement is effected without
the consent of the Company (which consent shall not be unreasonably withheld or
delayed); and provided further, that the Company will not be liable in any such
case to the extent that any such claim, loss, damage or liability arises out of
or is based on any untrue statement or omission made in reliance upon and
conformity with written information furnished to the Company specifically for
use therein by an instrument duly executed by such Holder.

                  (b)      Each Holder will, if Registrable Securities held by
or issuable to such Holder are included in the securities as to which such
registration, qualification or compliance is being effected, indemnify the
Company, each of its directors, officers and controlling persons, each
underwriter, if any, of the Company's securities covered by such a registration
statement, and each controlling person of such underwriter, and each other
Holder, each of its officers, directors, partners and controlling persons,
against all claims, losses, expenses, damages and liabilities (or actions in
respect thereof) arising out of or based on any untrue statement (or alleged
untrue statement) of a material fact contained in any such registration
statement, prospectus, offering circular or other document, or any omission (or
alleged omission) to state therein a material fact required to be stated therein
or necessary to make the statements therein not misleading, and will reimburse
the Company, such Holders, such directors, officers, partners, persons or
underwriters for any reasonable legal or any other expenses incurred in
connection with investigating, defending or settling any such claim, loss,
damage, liability or action, in each case to the extent, but only to the extent,
that such untrue statement (or alleged untrue statement) or omission (or alleged
omission) is made in such registration statement, prospectus, offering circular
or other document in reliance upon and in conformity with written information
furnished to the Company specifically for use therein by an instrument duly
executed by such Holder; provided, however, that the indemnity agreement
contained in this subsection 1.5(b) shall not apply to amounts paid in
settlement of any such claim, loss, damage, liability or action if such
settlement is effected without the consent of the Holder, (which consent shall
not be unreasonably withheld or delayed); and provided further, that the total
amount for which any Holder shall be liable under this subsection 1.5(b) shall
not in any event exceed the aggregate net proceeds received by such Holder from
the sale of Registrable Securities held by such Holder in such registration.

                  (c)      Each party entitled to indemnification under this
subsection 1.5 (the "Indemnified Party") shall give notice to the party required
to provide indemnification (the "Indemnifying Party") promptly after such
Indemnified Party has actual knowledge of any claim as to which indemnity may be
sought, and shall permit the Indemnifying Party to assume the defense of any
such claim or any litigation resulting therefrom; provided that counsel for the
Indemnifying Party, who shall conduct the defense of such claim or litigation,
shall be approved by the Indemnified Party (whose approval shall not


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be unreasonably withheld), and the Indemnified Party may participate in such
defense at such party's expense; and provided further, that the failure of any
Indemnified Party to give notice as provided herein shall not relieve the
Indemnifying Party of its obligations hereunder, unless such failure resulted in
prejudice to the Indemnifying Party; and provided further, that an Indemnified
Party (together with all other Indemnified Parties which may be represented
without conflict by one counsel) shall have the right to retain one separate
counsel, with the fees and expenses to be paid by the Indemnifying Party, if
representation of such Indemnified Party by the counsel retained by the
Indemnifying Party would be inappropriate due to actual or potential differing
interests between such Indemnified Party and any other party represented by such
counsel in such proceeding. No Indemnifying Party, in the defense of any such
claim or litigation, shall, except with the consent of each Indemnified Party,
consent to entry of any judgment or enter into any settlement which does not
include as an unconditional term thereof the giving by the claimant or plaintiff
to such Indemnified Party of a release from all liability in respect to such
claim or litigation.

                  (d)      In order to provide for just and equitable
contribution in circumstances in which the indemnification provided for in this
Section 1.5 is due in accordance with its terms but for any reason is judicially
determined to be unenforceable against the Indemnifying Party or otherwise
unavailable to the Indemnified Party in respect to any losses, claims, damages
and liabilities referred to herein, then the Indemnifying Party shall, in lieu
of indemnifying such Indemnified Party, contribute to the amount paid or payable
by such Indemnified party as a result of such losses, claims, damages or
liabilities to which such party may be subject in such proportion as is
appropriate to reflect the relative fault of the Company, on the one hand, and
the selling Holders, on the other hand, in connection with the statements or
omissions which resulted in such losses, claims, damages or liabilities, as well
as any other relevant equitable considerations. The relative fault of the
Company and such selling Holders shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement, or omission or
alleged omission, of material fact related to the information supplied by the
Company or such selling Holders and the parties' relative intent, knowledge,
access to information and opportunity to correct or prevent such statement or
omission. The Company and Holders agree that it would not be just and equitable
if contribution pursuant to this Section 1.5(d) were determined by pro rata
allocation or any other method of allocation which does not take account of the
equitable considerations referred to above. Notwithstanding the provisions of
this Section 1.5(d), (i) in no case shall any Holder be liable or responsible
for any amount in excess of the net proceeds received by such Holder from the
sale of Registrable Securities pursuant to such registration; and (ii) no person
adjudged 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 adjudged guilty of such fraudulent misrepresentation. Any party
entitled to contribution shall, promptly after receipt of notice of commencement
of any action, suit or proceeding against such party in respect of which a claim
for contribution may be made against another party or parties under this Section
1.5(d), notify such party or parties from whom contribution may be sought, but
the omission so to notify such party or parties from whom contribution may be
sought shall not, in the absence of actual prejudice to such party or parties,
relieve it or them from such contribution obligation. No party shall be liable
for contribution with respect to any action, suit, proceeding or claim settled
without its written consent.

         1.6      Information by Holder. Any Holder or Holders of Registrable
Securities included in any registration shall promptly furnish to the Company
such information regarding such Holder or Holders and the distribution proposed
by such Holder or Holders as the Company may request in writing and as shall be
required in connection with any registration, qualification or compliance
referred to herein.

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         1.7      Rule 144 Reporting. With a view to making available to Holders
the benefits of certain rules and regulations of the SEC which may permit the
sale of the Registrable Securities to the public without registration, the
Company agrees at all times to:

                  (a)      make and keep public information available, as those
terms are understood and defined in SEC Rule 144;

                  (b)      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

                  (c)      so long as a Holder owns any Registrable Securities,
to furnish to such Holder promptly following Holder's written request a written
statement by the Company as to its compliance with the reporting requirements of
said Rule 144 and of the Securities Act and the Exchange Act, a copy of the most
recent annual or quarterly report of the Company, and such other reports and
documents so filed by the Company as the Holder may reasonably request in
complying with any rule or regulation of the SEC allowing the Holder to sell any
such securities without registration.

         1.8      Transfer of Registration Rights. Holders' rights to cause the
Company to register their securities and keep information available, granted to
them by the Company under subsections 1.2 and 1.7 may be assigned to a
transferee or assignee of a Holder's Registrable Securities not sold to the
public, provided, that the Company is given written notice by such Holder at the
time of or within a reasonable time after said transfer, stating the name and
address of said transferee or assignee and identifying the securities with
respect to which such registration rights are being assigned.

         2        GENERAL.

         2.1      Waivers and Amendments. With the written consent of the record
or beneficial holders of at least a majority of the Registrable Securities, the
obligations of the Company and the rights of the Holders of the Registrable
Securities under this agreement may be waived (either generally or in a
particular instance, either retroactively or prospectively, and either for a
specified period of time or indefinitely), and with the same consent the
Company, when authorized by resolution of its Board of Directors, may enter into
a supplementary agreement for the purpose of adding any provisions to or
changing in any manner or eliminating any of the provisions of this Agreement;
provided, however, that no such modification, amendment or waiver shall reduce
the aforesaid percentage of Registrable Securities without the consent of all of
the Holders of the Registrable Securities. Upon the effectuation of each such
waiver, consent, agreement of amendment or modification, the Company shall
promptly give written notice thereof to the record holders of the Registrable
Securities who have not previously consented thereto in writing. This Agreement
or any provision hereof may be changed, waived, discharged or terminated only by
a statement in writing signed by the party against which enforcement of the
change, waiver, discharge or termination is sought, except to the extent
provided in this subsection 2.1.

         2.2      Governing Law. This Agreement shall be governed in all
respects by the laws of the Commonwealth of Massachusetts as such laws are
applied to agreements between Massachusetts residents entered into and to be
performed entirely within Massachusetts.


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         2.3      Successors and Assigns. Except as otherwise expressly provided
herein, the provisions hereof shall inure to the benefit of, and be binding
upon, the successors, assigns, heirs, executors and administrators of the
parties hereto.

         2.4      Entire Agreement. Except as set forth below, this Agreement
and the other documents delivered pursuant hereto constitute the full and entire
understanding and agreement between the parties with regard to the subjects
hereof and thereof.

         2.5      Notices, etc. All notices and other communications required or
permitted hereunder shall be in writing and shall be mailed by first class mail,
postage prepaid, certified or registered mail, return receipt requested,
addressed (a) if to Holder, at such Holder's address(es) as set forth below, or
at such other address(es) as such Holder shall have furnished to the Company in
writing, or (b) if to the Company, at the Company's address set forth below, or
at such other address as the Company shall have furnished to the Holder in
writing.

         2.6      Severability. In case any provision of this Agreement shall be
invalid, illegal, or unenforceable, the validity, legality and enforceability of
the remaining provisions of this Agreement or any provision of the other
Agreement s shall not in any way be affected or impaired thereby.

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

         2.8      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.

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         IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be executed by their duly authorized representatives as of the date
first above written.



SILICON VALLEY BANK                         EVERGREEN SOLAR, INC.


By:  /s/ David Rodriguez                   By:  /s/ Richard G. Chleboski
    --------------------------------            -------------------------------
         Name:  David E. Rodriguez                  Name: Richard G. Chleboski
         Title: VP                                  Title: Vice President

Address: One Newton Executive Park         Address: 138 Bartlett Street
         2221 Washington Street                     Marlboro, MA 01752
         Suite 200
         Newton, MA 02462

copy to: Silicon Valley Bank
         Treasury Department
         3003 Tasman Drive, HA 200
         Santa Clara, CA 95054






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