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Exhibit 10.120

[*]=Information redacted pursuant to a confidential treatment request. Such
outlined information has been filed separately with the Securities and Exchange
Commission.

        THE SECURITIES REPRESENTED BY THIS CERTIFICATE (THE "SECURITIES") HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
"SECURITIES ACT") OR ANY STATE SECURITIES LAWS AND MAY NOT BE SOLD, TRANSFERRED
OR OTHERWISE DISPOSED OF UNLESS REGISTERED UNDER THE SECURITIES ACT AND UNDER
APPLICABLE STATE SECURITIES LAWS OR COMMERCE ENERGY GROUP, INC. SHALL HAVE
RECEIVED AN OPINION OF COUNSEL THAT REGISTRATION OF SUCH SECURITIES UNDER THE
SECURITIES ACT AND UNDER THE PROVISIONS OF APPLICABLE STATE SECURITIES LAWS IS
NOT REQUIRED.

SENIOR SECURED CONVERTIBLE PROMISSORY NOTE

Dated: August 21, 2008   $20,931,579

        For value received, COMMERCE ENERGY, INC., a corporation organized under
the laws of the State of California and COMMERCE ENERGY GROUP, INC., a
corporation organized under the laws of the State of Delaware (collectively and
severally, the "Maker"), hereby promise to pay to the order of AP FINANCE, LLC,
a limited liability company organized under the laws of the State of Delaware,
with an address at 152 West 57th Street, 4th Floor, New York, NY 10019 (together
with its successors, representatives, and assigns, the "Holder"), in accordance
with the terms hereinafter provided, the principal amount of Twenty Million,
Nine Hundred Thirty One Thousand Five Hundred Seventy Nine Dollars ($20,931,579)
hereunder, together with interest and all other obligations outstanding
hereunder.

        All payments under or pursuant to this Senior Secured Convertible
Promissory Note (this "Note") shall be made in United States Dollars in
immediately available funds to the Holder at the address of the Holder first set
forth above or at such other place as the Holder may designate from time to time
in writing to the Maker or by wire transfer of funds to the Holder's account,
instructions for which are attached hereto as Exhibit A. The outstanding
principal balance of this Note shall be due and payable on December 22, 2008
(the "Maturity Date") or at such earlier time as provided herein. All
obligations and undertaking of, and references to, the Maker under this Note
shall be joint and several.

ARTICLE I

        Section 1.1    Purchase Agreement.    This Note has been executed and
delivered pursuant to the Note and Warrant Purchase Agreement, bearing even date
herewith (the "Purchase Agreement"), by and between the Maker and the Holder (as
a Lender). Capitalized terms used and not otherwise defined herein shall have
the meanings set forth for such terms in the Purchase Agreement.

        Section 1.2    Interest.    The outstanding principal balance of this
Note shall bear interest, in arrears, at a rate per annum equal to twelve
percent (12%), payable in cash on the Maturity Date. Interest shall be computed
on the basis of a 360-day year of twelve (12) thirty-day months, shall compound
monthly and shall accrue commencing on the date hereof. Furthermore, upon the
occurrence of an Event of Default (as defined in Section 2.1 hereof), the Maker
will pay interest to the Holder, payable on demand, on the outstanding principal
balance of the Note and on all unpaid interest from the date of the Event of
Default at a per annum rate equal to the lesser of eighteen percent (18%) and
the maximum applicable legal rate per annum, calculated based on a 360-day year.

        Section 1.3    Payment of Principal; Prepayment.    

        (a)   The principal amount hereof, plus an amount equal to 10%
outstanding principal amount, and plus all outstanding interest and all other
amounts due and owing hereunder, shall be paid in full on the Maturity Date or,
if earlier, upon acceleration of this Note in accordance with the terms hereof
Any amount of principal repaid hereunder may not be reborrowed. The Maker may

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prepay all (but not less than all) of the principal amount of this Note in an
amount equal to the sum of (i) 110% of the face value of this Note, and (ii) all
outstanding interest and all other amounts due and owing hereunder, upon not
less than three (3) Business Days prior written notice to the Holder, without
other penalty or premium.

        Section 1.4    Security Documents.    The obligations of the Maker
hereunder are secured by a continuing security interest in substantially all of
the assets of the Maker pursuant to the terms of a Security Agreement bearing
even date herewith by and between the Maker and the Holder and other collateral
documents.

        Section 1.5    Payment on Non-Business Days.    Whenever any payment to
be made shall be due on a Saturday, Sunday or a public holiday under the laws of
the State of New York, such payment shall be due on the next succeeding Business
Day and such next succeeding day shall be included in the calculation of the
amount of accrued interest payable on such date.

        Section 1.6    Transfer.    This Note may be transferred or sold, and
may also be pledged, hypothecated or otherwise granted as security, by the
Holder; provided, however, that any transfer or sale of this Note must be in
compliance with any applicable securities laws.

        Section 1.7    Replacement.    Upon receipt of a duly executed,
notarized and unsecured written statement from the Holder with respect to the
loss, theft or destruction of this Note (or any replacement hereof) and a
standard indemnity, or, in the case of a mutilation of this Note, upon surrender
and cancellation of such Note, the Maker shall issue a new Note, of like tenor
and amount, in lieu of such lost, stolen, destroyed or mutilated Note.

        Section 1.8    Use of Proceeds.    The Maker shall use the proceeds of
this Note as set forth in the Purchase Agreement.

ARTICLE II

EVENTS OF DEFAULT; REMEDIES

        Section 2.1    Events of Default.    The occurrence of any of the
following events shall be an "Event of Default" under this Note:

        (a)   any default in respect of any payment of the principal amount,
interest or any other monetary obligation under this Note, as and when the same
shall be due and payable (whether on the Maturity Date or by acceleration or
otherwise) or within three (3) days thereafter; or

        (b)   the occurrence of any Event of Default under the terms of the
Second Note (as such term is defined in the Purchase Agreement); or

        (c)   the Maker shall fail to observe or perform any other condition,
covenant or agreement contained in this Note; or

        (d)   other than a suspension relating to the failure of the American
Stock Exchange to approve the listing application being filed in connection with
the transactions contemplated hereby, the suspension from listing, without
subsequent listing on any one of, or the failure of the Common Stock to be
listed on at least one of the OTC Bulletin Board, the American Stock Exchange,
the Nasdaq Capital Markets, the Nasdaq Global Market, the Nasdaq Global Select
Market or The New York Stock Exchange, Inc. for a period of five (5) consecutive
Trading Days, such a suspension to only constitute an Event of Default if the
Holder provides the Maker written notification that it deems such suspension to
be an Event of Default; or

        (e)   the Maker shall default in the performance or observance of
(i) any undertaking, covenant, condition or agreement contained in the Purchase
Agreement or any other Transaction Document; or

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        (f)    any representation or warranty made by the Maker herein or in the
Purchase Agreement or any other Transaction Document shall prove to have been
false or incorrect or breached in a material respect on the date as of which
made; or

        (g)   (A) a default in any payment of any amount or amounts of principal
of or interest on any Indebtedness of the Maker (other than the Indebtedness
hereunder) the aggregate principal amount of which Indebtedness is in excess of
$100,000 or (B) a default in the observance or performance of any other
agreement or condition relating to any Indebtedness or contained in any
instrument or agreement evidencing, securing or relating thereto, or any other
event shall occur or condition exist, the effect of which default or other event
or condition is to cause, or to permit the holder or holders or beneficiary or
beneficiaries of such Indebtedness to cause with the giving of notice if
required, such Indebtedness to become due prior to its stated maturity; or

        (h)   the Maker shall (i) apply for or consent to the appointment of, or
the taking of possession by, a receiver, custodian, trustee or liquidator of
itself or of all or a substantial part of its property or assets, (ii) make a
general assignment for the benefit of its creditors, (iii) commence a voluntary
case under the United States Bankruptcy Code (as now or hereafter in effect) or
under the comparable laws of any jurisdiction (foreign or domestic), (iv) file a
petition seeking to take advantage of any bankruptcy, insolvency, moratorium,
reorganization or other similar law affecting the enforcement of creditors'
rights generally, (v) acquiesce in writing to any petition filed against it in
an involuntary case under United States Bankruptcy Code (as now or hereafter in
effect) or under the comparable laws of any jurisdiction (foreign or domestic),
(vi) issue a notice of bankruptcy or winding down of its operations or issue a
press release regarding same, or (vii) take any action under the laws of any
jurisdiction (foreign or domestic) analogous to any of the foregoing; or

        (i)    a proceeding or case shall be commenced in respect of the Maker,
without its application or consent, in any court of competent jurisdiction,
seeking (i) the liquidation, reorganization, moratorium, dissolution, winding
up, or composition or readjustment of its debts, (ii) the appointment of a
trustee, receiver, custodian, liquidator or the like of it or of all or any
substantial part of its assets in connection with the liquidation or dissolution
of the Maker or (iii) similar relief in respect of it under any law providing
for the relief of debtors, and such proceeding or case described in clause (i),
(ii) or (iii) shall continue undismissed, or unstayed and in effect, for a
period of sixty (60) days or any order for relief shall be entered in an
involuntary case under United States Bankruptcy Code (as now or hereafter in
effect) or under the comparable laws of any jurisdiction (foreign or domestic)
against the Maker or action under the laws of any jurisdiction (foreign or
domestic) analogous to any of the foregoing shall be taken with respect to the
Maker and shall continue undismissed, or unstayed and in effect for a period of
sixty (60) days; or

        (j)    a judgment or judgments in the aggregate amount exceeding
$100,000 is/are entered against the Maker and not dismissed or discharged within
twenty (20) days following the entry thereof; or

        (k)   Maker shall cease to actively conduct its business operations for
a period of five (5) consecutive Business Days; or

        (1)   any material portion of the properties or assets of the Maker is
seized by any governmental authority; or

        (n)   the Maker is indicted for the commission of any criminal activity;
or

        (o)   closing of a purchase, tender or exchange offer made to the
holders of more than fifty percent (50%) of the outstanding shares of Common
Stock in which more than fifty percent (50%) of the outstanding shares of Common
Stock were tendered and accepted.

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        Section 2.2    Remedies Upon An Event of Default.    If an Event of
Default shall have occurred and shall be continuing, the Collateral Agent may at
any time at its option (a) declare the entire unpaid principal balance of this
Note, together with all interest accrued hereon, plus fees and expenses, due and
payable, and thereupon, the same shall be accelerated and so due and payable,
without presentment, demand, protest, or notice, all of which are hereby
expressly unconditionally and irrevocably waived by the Maker; provided,
however, that upon the occurrence of an Event of Default described in
Sections 2.1 (h) or (i) above, the outstanding principal balance and accrued
interest hereunder, plus fees and expenses, shall be immediately and
automatically due and payable, and/or (b) exercise or otherwise enforce any one
or more of the Holder's rights, powers, privileges, remedies and interests as
well as its own rights, powers and remedies under this Note, the Purchase
Agreement, the Security Agreement or other Transaction Document or applicable
law. No course of delay on the part of the Holder shall operate as a waiver
thereof or otherwise prejudice the right of the Holder. No remedy conferred
hereby shall be exclusive of any other remedy referred to herein or now or
hereafter available at law, in equity, by statute or otherwise. Upon and after
an Event of Default, this Note shall bear interest at the default rate set forth
in Section 1.2 hereof.

ARTICLE III

CONVERSION; ANTIDILUTION

        Section 3.1    Conversion Option.    At any time and from time to time
on or after the Issuance Date, this Note shall be convertible (in whole or in
part), at the option of the Holder (the "Conversion Option"), into such number
of fully paid and non-assessable shares of Common Stock (the "Conversion Rate")
as is determined by dividing (x) that portion of the outstanding principal
balance plus any accrued but unpaid interest under this Note as of such date
that the Holder elects to convert by (y) the Conversion Price (as defined in
Section 3.2 hereof) then in effect on the date on which the Holder delivers a
notice of conversion (the "Conversion Notice"), duly executed, to the Company
(the "Voluntary Conversion Date"), provided, however, that the Conversion Price
shall be subject to adjustment as described in Section 3.5 below. The Holder
shall deliver this Note to the Company at the address designated in the Purchase
Agreement at such time that this Note is fully converted. With respect to
partial conversions of this Note, the Company shall keep written records of the
amount of this Note converted as of each Conversion Date.

        Section 3.2    Conversion Price.    The term "Conversion Price" shall
mean $3.00, subject to adjustment under Section 3.5 hereof (the "Set Price").

        Section 3.3    Mechanics of Conversion.    

        (a)   Not later than three (3) Trading Days after any Conversion Date,
the Company or its designated transfer agent, as applicable, shall issue and
deliver to the Depository Trust Company ("DTC") account on the Holder's behalf
via the Deposit Withdrawal Agent Commission System ("DWAC") as specified in the
Conversion Notice, registered in the name of the Holder or its affiliates, for
the number of shares of Common Stock to which the Holder shall be entitled. In
the alternative, not later than three (3) Trading Days after any Conversion
Date, the Company shall deliver to the applicable Holder by express courier a
certificate or certificates which shall be free of restrictive legends and
trading restrictions (other than those required by Section 5.1 of the Purchase
Agreement) representing the number of shares of Common Stock being acquired upon
the conversion of this Note (the "Delivery Date"). Notwithstanding the foregoing
to the contrary, the Company or its transfer agent shall only be obligated to
issue and deliver the shares to the DTC on the Holder's behalf via DWAC (or
certificates free of restrictive legends) if such conversion is in connection
with a sale and the Holder has complied with the applicable prospectus delivery
requirements (as evidenced by documentation furnished to and reasonably
satisfactory to the Company) or such shares may be sold pursuant to Rule 144 or
other exemption under the Securities Act. If in the case of any Conversion

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Notice such certificate or certificates are not delivered to or as directed by
the applicable Holder by the Delivery Date, the Holder shall be entitled by
written notice to the Company at any time on or before its receipt of such
certificate or certificates thereafter, to rescind such conversion, in which
event the Company shall immediately return this Note tendered for conversion,
whereupon the Company and the Holder shall each be restored to their respective
positions immediately prior to the delivery of such notice of revocation, except
that any amounts described in Sections 3.3(b) and (c) shall be payable through
the date notice of rescission is given to the Company.

        (b)   The Company understands that a delay in the delivery of the shares
of Common Stock upon conversion of this Note beyond the Delivery Date could
result in economic loss to the Holder. If the Company fails to deliver to the
Holder such shares via DWAC (or, if applicable, certificates) by the Delivery
Date, the Company shall pay to such Holder, in cash, an amount per Trading Day
for each Trading Day until such shares are delivered via DWAC or certificates
are delivered (if applicable), together with interest on such amount at a rate
of 10% per annum, accruing until such amount and any accrued interest thereon is
paid in full, equal to the greater of (A) 2% of the aggregate principal amount
of the Notes requested to be converted for each Trading Day and (B) $2,000 per
day (which amount shall be paid as liquidated damages and not as a penalty).
Nothing herein shall limit a Holder's right to pursue actual damages for the
Company's failure to deliver certificates representing shares of Common Stock
upon conversion within the period specified herein and such Holder shall have
the right to pursue all remedies available to it at law or in equity (including,
without limitation, a decree of specific performance and/or injunctive relief).
Notwithstanding anything to the contrary contained herein, the Holder shall be
entitled to withdraw a Conversion Notice, and upon such withdrawal the Company
shall only be obligated to pay the liquidated damages accrued in accordance with
this Section 3.3(b) through the date the Conversion Notice is withdrawn.

        (c)   In addition to any other rights available to the Holder, if the
Company fails to cause its transfer agent to transmit via DWAC or transmit to
the Holder a certificate or certificates representing the shares of Common Stock
issuable upon conversion of this Note on or before the Delivery Date, and if
after such date the Holder is required by its broker to purchase (in an open
market transaction or otherwise) shares of Common Stock to deliver in
satisfaction of a sale by the Holder of the shares of Common Stock issuable upon
conversion of this Note which the Holder anticipated receiving upon such
conversion (a "Buy-In"), then the Company shall (1) pay in cash to the Holder
the amount by which (x) the Holder's total purchase price (including brokerage
commissions, if any) for the shares of Common Stock so purchased exceeds (y) the
amount obtained by multiplying (A) the number of shares of Common Stock issuable
upon conversion of this Note that the Company was required to deliver to the
Holder in connection with the conversion at issue times (B) the price at which
the sell order giving rise to such purchase obligation was executed, and (2) at
the option of the Holder, either reinstate the portion of the Note and
equivalent number of shares of Common Stock for which such conversion was not
honored or deliver to the Holder the number of shares of Common Stock that would
have been issued had the Company timely complied with its conversion and
delivery obligations hereunder. For example, if the Holder purchases Common
Stock having a total purchase price of $11,000 to cover a Buy-In with respect to
an attempted conversion of shares of Common Stock with an aggregate sale price
giving rise to such purchase obligation of $10,000, under clause (1) of the
immediately preceding sentence the Company shall be required to pay the Holder
$1,000. The Holder shall provide the Company written notice indicating the
amounts payable to the Holder in respect of the Buy-In, together with applicable
confirmations and other evidence reasonably requested by the Company. Nothing
herein shall limit a Holder's right to pursue any other remedies available to it
hereunder, at law or in equity including, without limitation, a decree of
specific performance and/or injunctive relief with respect to the Company's
failure to timely deliver certificates representing shares of Common Stock upon
conversion of this Note as required pursuant to the terms hereof.

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        Section 3.4    Ownership Cap and Certain Conversion Restrictions.    

        (a)   Notwithstanding anything to the contrary set forth in Section 3 of
this Note, at no time may the Holder convert all or a portion of this Note if
the number of shares of Common Stock to be issued pursuant to such conversion,
when aggregated with all other shares of Common Stock owned by the Holder at
such time, would result in the Holder beneficially owning (as determined in
accordance with Section 13(d) of the Exchange Act and the rules thereunder) in
'excess of 4.99% of the then issued and outstanding shares of Common Stock
outstanding at such time; provided, however, that upon the Holder providing the
Company with 61 days' prior written notice that the Holder would like to waive
Section 3.4(a) of this Note with regard to any or all shares of Common Stock
issuable upon conversion of this Note, this Section 3.4(a) shall be of no force
or effect with regard to all or a portion of the Note referenced in the waiver
notice.

        Section 3.5    Trading Market Regulation.    The Company shall not be
obligated to issue any shares of Common Stock upon conversion of this Note if
the issuance of such shares of Common Stock would exceed the aggregate number of
shares of Common Stock which the Company may issue upon conversion or exercise,
as applicable, of the Notes, Warrants and additional warrants to purchase up to
875,000 shares of Common Stock issuable to finders and placement agents in
connection with transactions contemplated by the Purchase Agreement in the
aggregate without breaching the Company's obligations under the rules or
regulations of any applicable Trading Market, except that such limitation shall
not apply in the event that the Company (A) obtains the approval of its
stockholders as required by the applicable rules of such Trading Market for
issuances of Common Stock in excess of such amount or (B) obtains a written
opinion from outside counsel to the Company that such approval is not required,
which opinion shall he reasonably satisfactory to the Holder.

        Section 3.6    Adjustment of Conversion Price.    

        (a)   Until the Note has been paid in full or converted in full, the Set
Price shall be subject to adjustment from time to time as follows (but shall not
be increased, other than pursuant to Section 3.5(a)(i) hereof):

        (i)    Adjustments for Stock Splits and Combinations.    If the Company
shall at any time or from time to time after the date hereof (the "Issuance
Date"), effect a stock split of the outstanding Common Stock, the applicable Set
Price in effect immediately prior to the stock split shall be proportionately
decreased. If the Company shall at any time or from time to time after the
Issuance Date, combine the outstanding shares of Common Stock, the applicable
Set Price in effect immediately prior to the combination shall be
proportionately increased. Any adjustments under this Section 3.5(a)(i) shall be
effective at the close of business on the date the stock split or combination
occurs.

        (ii)    Adjustments for Certain Dividends and Distributions.    If the
Company shall at any time or from time to time after the Issuance Date, make or
become irrevocably obligated to issue the holders of Common Stock a dividend or
other distribution payable in shares of Common Stock, then, and in each event,
the applicable Set Price in effect immediately prior to such event shall be
decreased as of the time of such issuance or, in the event a record date shall
have been fixed, as of the close of business on such record date, by
multiplying, the applicable Set Price then in effect by a fraction:

        (1)   the numerator of which shall be the total number of shares of
Common Stock issued and outstanding immediately prior to the time of such
issuance or the close of business on such record date; and

        (2)   the denominator of which shall be the total number of shares of
Common Stock issued and outstanding immediately prior to the time of such
issuance or the close of business on such record date plus the number of shares
of Common Stock issuable in payment of such dividend or distribution.

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        (iii)    Adjustment for Other Dividends and Distributions.    If the
Company shall at any time or from time to time after the Issuance Date, make or
become irrevocably obligated to issue the holders of its Common Stock a dividend
or other distribution payable in other than shares of Common Stock, then, and in
each event, an appropriate revision to the applicable Set Price shall be made
and provision shall be made (by adjustments of the Set Price or otherwise) so
that the holders of this Note shall receive upon conversions thereof, in
addition to the number of shares of Common Stock receivable thereon, the number
of securities of the Company or other issuer (as applicable) which they would
have received had this Note been converted into Common Stock on the date of such
event and had thereafter, during the period from the date of such event to and
including the Conversion Date, retained such securities (together with any
distributions payable thereon during such period), giving application to all
adjustments called for during such period under this Section 3.5(a)(iii) with
respect to the rights of the holders of this Note; provided, however, that if a
record date shall have been fixed and such dividend is not fully paid or if such
distribution is not fully made on the date fixed therefor, the Set Price shall
be adjusted pursuant to this paragraph as of the time of actual payment of such
dividends or distributions.

        (iv)    Adjustments for Reclassification, Exchange or
Substitution.    If the Common Stock issuable upon conversion of this Note at
any time or from time to time after the Issuance Date shall be changed to the
same or different number of shares of any class or classes of stock, whether by
reclassification, exchange, substitution or otherwise (other than by way of a
stock split or combination of shares or stock dividends provided for in
Sections 3.5(a)(i), (ii) and (iii), or a reorganization, merger, consolidation,
or sale of assets provided for in Section 3.5(a)(v)), then, and in each event,
an appropriate revision to the Set Price shall be made and provisions shall be
made (by adjustments of the Set Price or otherwise) so that the Holder shall
have the right thereafter to convert this Note into the kind and amount of
shares of stock and other securities receivable upon reclassification, exchange,
substitution or other change, by holders of the number of shares of Common Stock
into which such Note might have been converted immediately prior to such
reclassification, exchange, substitution or other change, all subject to further
adjustment as provided herein.

        (v)    Adjustments for Reorganization, Merger, Consolidation or Sales of
Assets.    If at any time or from time to time after the Issuance Date there
shall be a capital reorganization of the Company (other than by way of a stock
split or combination of shares or stock dividends or distributions provided for
in Section 3.5(a)(i), (ii) and (iii), or a reclassification, exchange or
substitution of shares provided for in Section 3.5(a)(iv)), or a merger or
consolidation of the Company with or into another Person where the holders of
outstanding voting securities prior to such merger or consolidation do not own
over fifty percent (50%) of the outstanding voting securities of the merged or
consolidated entity, immediately after such merger or consolidation, or the sale
of all or substantially all of the Company's properties or assets to any other
Person (an "Organic Change"), then as a part of such Organic Change, (A) if the
surviving entity in any such Organic Change is a public company the traded
equity securities of which are registered pursuant to the Securities Exchange
Act of 1934, as amended, and such securities are listed or quoted on a national
securities exchange (as defined in the Securities Exchange Act of 1934) or the
OTC Bulletin Board, an appropriate revision to the Set Price shall be made and
provision shall be made (by adjustments of the Set Price or otherwise) so that
the Holder shall have the right thereafter to convert such Note into the kind
and amount of shares of stock and other securities or property of the Company or
any successor corporation resulting from Organic Change, and (B) if the
surviving entity in any such Organic Change is not such a public company, or its
equity securities are not listed or quoted on a national securities exchange or
the OTC Bulletin Board, the Holder shall have the right to demand prepayment
pursuant to Section 1.3(b) hereof. In any such case, appropriate adjustment
shall be made in the application of the provisions of this Section 3.5(a)(v)
with respect to the rights of the Holder after the Organic Change to the end
that the provisions of

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this Section 3.5(a)(v) (including any adjustment in the applicable Set Price
then in effect and the number of shares of stock or other securities deliverable
upon conversion of this Note) shall be applied after that event in as nearly an
equivalent manner as may be practicable.

        (d)    No Impairment.    The Company shall not, by amendment of its
Articles of Incorporation or through any reorganization, transfer of assets,
consolidation, merger, dissolution, issue or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be observed or performed hereunder by the Company, but will at all
times in good faith, assist in the carrying out of all the provisions of this
Section 3.5 and in the taking of all such action as may be necessary or
appropriate in order to protect the Conversion Rights of the Holder against
impairment. In the event the Holder shall elect to convert the Note as provided
herein, the Company cannot refuse conversion based on any claim that the Holder
or any one associated or affiliated with the Holder has been engaged in any
violation of law, violation of an agreement to which the Holder is a party or
for any reason whatsoever, unless, an injunction from a court, or notice,
restraining and or adjoining conversion of the Note shall have issued and the
Company posts a surety bond for the benefit of the Holder in an amount equal to
one hundred fifty percent (150%) of the amount of the Notes, which bond shall
remain in effect until the completion of arbitration/litigation of the dispute
and the proceeds of which shall be payable to the Holder (as liquidated damages)
in the event it obtains judgment.

        (e)    Certificates as to Adjustments.    Upon occurrence of each
adjustment or readjustment of the Conversion Price or number of shares of Common
Stock issuable upon conversion of this Note pursuant to this Section 3.5, the
Company at its expense shall promptly compute such adjustment or readjustment in
accordance with the terms hereof and furnish to the older a certificate setting
forth such adjustment and readjustment, showing in detail the facts upon which
such adjustment or readjustment is based. The Company shall, upon written
request of the Holder, at any time, furnish or cause to be furnished to the
Holder a like certificate setting forth such adjustments and readjustments, the
applicable Conversion Price in effect at the time, and the number of shares of
Common Stock and the amount, if any, of other securities or property which at
the time would be received upon the conversion of this Note. Notwithstanding the
foregoing, the Company shall not be obligated to deliver a certificate unless
such certificate would reflect an increase or decrease of at least one percent
(1%) of such adjusted amount.

        (f)    Issue Taxes.    The Company shall pay any and all issue and other
taxes, excluding federal, state or local income taxes, that may be payable in
respect of any issue or delivery of shares of Common Stock on conversion of this
Note pursuant thereto; provided, however, that the Company shall not be
obligated to pay any transfer taxes resulting from any transfer requested by the
Holder in connection with any such conversion.

        (g)    Fractional Shares.    No fractional shares of Common Stock shall
be issued upon conversion of this Note. In lieu of any fractional shares to
which the Holder would otherwise be entitled, the Company shall pay cash equal
to the product of such fraction multiplied by the average of the Closing Bid
Prices of the Common Stock for the five (5) consecutive Trading Days immediately
preceding the Conversion Date.

        (h)    Reservation of Common Stock.    The Company shall at all times
when this Note shall be outstanding, reserve and keep available out of its
authorized but unissued Common Stock, such number of shares of Common Stock as
shall from time to time be sufficient to effect the conversion of this Note and
all interest accrued thereon; provided that the number of shares of Common Stock
so reserved shall at no time be less than one hundred fifty percent (150%) of
the number of shares of Common Stock for which this Note and all interest
accrued thereon are at any time convertible. The Company shall, from time to
time in accordance with Delaware law, increase the authorized number of shares
of Common Stock if at any time the unissued number of

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authorized shares shall not be sufficient to satisfy the Company's obligations
under this Section 3.5(h).

        (i)    Regulatory Compliance.    If any shares of Common Stock to be
reserved for the purpose of conversion of this Note or any interest accrued
thereon require registration or listing with or approval of any governmental
authority, stock exchange or other regulatory body under any federal or state
law or regulation or otherwise before such shares may be validly issued or
delivered upon conversion, the Company shall, at its sole cost and expense, in
good faith and as expeditiously as possible, endeavor to secure such
registration, listing or approval, as the case may be.

ARTICLE IV

MISCELLANEOUS

        Section 4.1    Notices.    Any notice, demand, request, waiver or other
communication required or permitted to be given hereunder shall be in writing
and shall be effective (a) upon hand delivery, telecopy or facsimile at the
address or number designated in the Purchase Agreement (if delivered on a
Business Day during normal business hours where such notice is to be received),
or the first Business Day following such delivery (if delivered other than on a
Business Day during normal business hours where such notice is to be received)
or (b) on the second Business Day following the date of mailing by express
courier service, fully prepaid, addressed to such address, or upon actual
receipt of such mailing, whichever shall first occur.

        Section 4.2    Governing Law.    This Note shall be governed by and
construed in accordance with the internal laws of the State of New York, without
giving effect to any of the conflicts of law principles which would result in
the application of the substantive law of another jurisdiction. This Note shall
not be interpreted or construed with any presumption against the party causing
this Note to be drafted.

        Section 4.3    Headings.    Article and section headings in this Note
are included herein for purposes of convenience of reference only and shall not
constitute a part of this Note for any other purpose.

        Section 4.4    Remedies, Characterizations, Other Obligations, Breaches
and Injunctive Relief.    The remedies provided in this Note shall be cumulative
and in addition to all other remedies available under this Note, at law or in
equity (including, without limitation, a decree of specific performance and/or
other injunctive relief), no remedy contained herein shall be deemed a waiver of
compliance with the provisions giving rise to such remedy and nothing herein
shall limit a holder's right to pursue actual damages for any failure by the
Maker to comply with the terms of this Note. Amounts set forth or provided for
herein with respect to payments, conversion and the like (and the computation
thereof) shall be the amounts to be received by the holder thereof and shall
not, except as expressly provided herein, be subject to any other obligation of
the Maker (or the performance thereof). The Maker acknowledges that a breach by
it of its obligations hereunder will cause irreparable and material harm to the
Holder and that the remedy at law for any such breach may be inadequate.
Therefore the Maker agrees that, in the event of any such breach or threatened
breach, the Holder shall be entitled, in addition to all other available rights
and remedies, at law or in equity, to seek and obtain such equitable relief,
including but not limited to an injunction restraining any such breach or
threatened breach, without the necessity of showing economic loss and without
any bond or other security being required.

        Section 4.5    Enforcement Expenses.    The Maker agrees to pay all
costs and expenses incurred from time to time by the Holder with respect to any
modification, consent or waiver of the provisions of this Note or the
Transaction Documents and any enforcement of this Note and the Transaction
Documents, including, without limitation, reasonable attorneys' fees and
expenses.

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        Section 4.6    Amendments.    

        (a)   This Note may not be modified or amended in any manner except in
writing executed by the Maker and the Holder.

        (b)   To the extent that amendments to this Note are required in
connection with the filing of a listing application with the American Stock
Exchange in connection with the transactions contemplated hereby, the Maker and
the Holder shall cooperate in good faith to reach mutually acceptable
resolutions with regard to such amendments, without penalty; provided that the
Holder has, in its sole discretion, determined such amendments to be advisable.

        Section 4.7    Compliance with Securities Laws.    

        (a)   The Holder of this Note acknowledges that this Note is being
acquired solely for the Holder's own account and not as a nominee for any other
party, and for investment, and that the Holder shall not offer, sell or
otherwise dispose of this Note except in accordance with applicable law.

        (b)   The Holder is an "accredited investor" (as defined in Rule 501 of
Regulation D under the Securities Act), and such Holder has such experience in
business and financial flatters that it is capable of evaluating the merits and
risks of an investment in the Securities. The Holder is not required to be
registered as a broker-dealer under Section 15 of the Exchange Act and it is not
a broker-dealer. The Holder acknowledges that an investment in the Securities is
speculative and involves a high degree of risk.

        Section 4.8    Consent to Jurisdiction.    Each of the Maker and the
Holder (i) hereby irrevocably submits to the exclusive jurisdiction of the
United States District Court sitting in the Southern District of New York and
the courts of the State of New York located in New York county for the purposes
of any suit, action or proceeding arising out of or relating to this Note and
(ii) hereby waives, and agrees not to assert in any such suit, action or
proceeding, any claim that it is not personally subject to the jurisdiction of
such court, that the suit, action or proceeding is brought in an inconvenient
forum or that the venue of the suit, action or proceeding is improper. Each of
the Maker and the Holder consents to process being served in any such suit,
action or proceeding by mailing a copy thereof to such party at the address in
effect for notices to it under the Purchase Agreement and agrees that such
service shall constitute good and sufficient service of process and notice
thereof. Nothing in this Section 3.8 shall affect or limit any right to serve
process in any other manner permitted by law.

        Section 4.9    Binding Effect.    This Note shall be binding upon, inure
to the benefit of and be enforceable by the Maker, the Holder and their
respective successors and permitted assigns. The Maker shall not delegate or
transfer this Note or any obligations or undertakings contained in this Note.

        Section 4.10    Failure or Indulgence Not Waiver.    No failure or delay
on the part of the Holder in the exercise of any power, right or privilege
hereunder shall operate as a waiver thereof, nor shall any single or partial
exercise of any such power, right or privilege preclude other or further
exercise thereof or of any other right, power or privilege.

        Section 4.11    Maker Waivers: Dispute Resolution.    

        (a)   Except as otherwise specifically provided herein, the Maker and
all others that may become liable for all or any part of the obligations
evidenced by this Note, hereby waive presentment, demand, notice of nonpayment,
protest and all other demands' and notices in connection with the delivery,
acceptance, performance and enforcement of this Note, and do hereby consent to
any number of renewals of extensions of the time or payment hereof and agree
that any such renewals or extensions may be made without notice to any such
persons and without affecting their liability herein and do further consent to
the release of any person liable hereon, all without affecting the liability of
the other persons, firms or Maker liable for the payment of this Note, AND DO
HEREBY WAIVE TRIAL BY JURY.

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        (b)   No delay or omission on the part of the Holder in exercising its
rights under this Note, or course of conduct relating hereto, shall operate as a
waiver of such rights or any other right of the Holder, nor shall any waiver by
the Holder of any such right or rights on any one occasion be deemed a waiver of
the same right or rights on any future occasion.

        (c)   THE MAKER ACKNOWLEDGES THAT THE TRANSACTION OF WHICH THIS NOTE IS
A PART IS A COMMERCIAL TRANSACTION, AND TO THE EXTENT ALLOWED BY APPLICABLE LAW,
HEREBY WAIVES ITS RIGHT TO NOTICE AND HEARING WITH RESPECT TO ANY PREJUDGMENT
REMEDY WHICH THE HOLDER OR ITS SUCCESSORS OR ASSIGNS MAY DESIRE TO USE.

        Section 4.12    Definitions.    Terms used herein and not defined shall
have the meanings set forth in the Purchase Agreement. For the purposes hereof,
the following terms shall have the following meanings:

        "Business Day" (whether or not capitalized) shall mean any day banking
transactions can be conducted in New York City, NY, USA and does not include any
day which is a federal or state holiday in such location.

        "Closing Bid Price" means, on any particular date (i) the last trading
price per share of the Common Stock on such date on the OTC Bulletin Board or
another registered national securities exchange on which the Common Stock is
then listed, or if there is no such price on such date, then the last trading
price on such exchange or quotation system on the date nearest preceding such
date, or (ii) if the Common Stock is not then listed or traded on a registered
national securities exchange or quoted on the OTC Bulletin Board, then the
average of the "Pink Sheet" quotes for the relevant conversion period, as
determined in good faith by the Holder, or (iii) if the Common Stock is not then
publicly traded the fair market value of a share of Common Stock as determined
by the Holder and reasonably acceptable to the Maker.

        "Common Stock" means shares of common stock, par value $0.001 per share,
of the Company.

        "Company" means Commerce Energy Group, Inc., a Delaware corporation.

        "Person" means an individual or a corporation, partnership, trust,
incorporated or unincorporated association, joint venture, limited liability
company, joint stock company, government (or an agency or political subdivision
thereof) or other entity of any kind.

        "Trading Day" means (a) a day on which the Common Stock is traded on the
OTC Bulletin Board or a registered national securities exchange, or (b) if the
Common Stock is not traded on the OTC Bulletin Board or a registered national
securities exchange, a day on which the Common Stock is quoted in the
over-the-counter market as reported by the National Quotation Bureau
Incorporated (or any similar organization or agency succeeding its functions of
reporting prices); provided, however, that in the event that the Common Stock is
not listed or quoted as set forth in (a) or (b) hereof, then Trading Day shall
mean any day. except Saturday, Sunday and any day which shall be a legal holiday
or a day on which banking institutions in the State of New York are authorized
or required by law or other government action to close.

        "Trading Market" means the Over the Counter Bulletin Board, the New York
Stock Exchange, the Nasdaq Capital Markets, the Nasdaq Global Markets, the
Nasdaq Global Select Market or the American Stock Exchange.

        "Transaction Documents" means this Note, the Purchase Agreement, the
Security Agreement, and all other security documents or related agreements now
or hereafter entered into in connection with and/or as security for this Note
and all amendments and supplements thereto and replacements thereof and any
other Transaction Document (as that term is defined in the Purchase Agreement).

[Signature appears on following page]

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        IN WITNESS WHEREOF, each Maker has caused this Note to be duly executed
by its duly authorized officer as of the date first above indicated.

  COMMERCE ENERGY, INC,

 

By:

 

/s/ Gregory L. Craig

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  Name:   Gregory L. Craig

  Title:   Chief Executive Officer

 

COMMERCE ENERGY GROUP, INC.

 

By:

 

/s/ Gregory L. Craig

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  Name:   Gregory L. Craig

  Title:   Chief Executive Officer

[SIGNATURE PAGE TO SENIOR SECURED
CONVERTIBLE PROMISSORY NOTE]

S-1

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EXHIBIT A

WIRE INSTRUCTIONS

Wire instructions for AP Finance, LLC

Bank:   Commerce Bank
ABA#:
 
[*]
Account Name:
 
AP Finance, LLC
Account Number:
 
[*]

EXHIBIT B

   

   

   

[*]=Information redacted pursuant to a confidential treatment request. Such
outlined information has been filed separately with the Securities and Exchange
Commission.

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EXHIBIT B

FORM OF

NOTICE OF CONVERSION

(To be Executed by the Registered Holder in order to Convert the Note)

The undersigned hereby irrevocably elects to convert $                  of the
principal amount of the above Note No.        into shares of Common Stock of
Commerce Energy Group, Inc. (the "Maker") according to the conditions hereof, as
of the date written below.

Date of Conversion  

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Applicable Conversion Price  

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Number of shares of Common Stock beneficially owned or deemed beneficially owned
by the Holder on the
Date of Conversion:    

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Signature  

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[Name]

Address:  

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EXHIBIT B

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QuickLinks

Exhibit 10.120

SENIOR SECURED CONVERTIBLE PROMISSORY NOTE
ARTICLE I
ARTICLE II
EVENTS OF DEFAULT; REMEDIES
ARTICLE III
CONVERSION; ANTIDILUTION
ARTICLE IV
MISCELLANEOUS