WC-[    ]

NEITHER THIS WARRANT NOR THE SHARES OF COMMON STOCK  ISSUABLE  UPON  EXERCISE OF
THIS WARRANT HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 ( THE "ACT"),
AND NEITHER  THIS WARRANT NOR SUCH SHARES MAY BE SOLD,  ENCUMBERED  OR OTHERWISE
TRANSFERRED  EXCEPT PURSUANT TO AN EFFECTIVE  REGISTRATION  STATEMENT UNDER SUCH
ACT OR AN EXEMPTION  FROM SUCH  REGISTRATION  REQUIREMENT,  AND, IF AN EXEMPTION
SHALL BE APPLICABLE,  THE  REGISTERED  HOLDER SHALL HAVE DELIVERED AN OPINION OF
COUNSEL  REASONABLY  ACCEPTABLE  TO THE COMPANY  THAT SUCH  REGISTRATION  IS NOT
REQUIRED.


                SERIES C REDEEMABLE COMMON STOCK PURCHASE WARRANT
                                       OF
                            U.S. ENERGY SYSTEMS, INC.


This is to certify  that,  FOR VALUE  RECEIVED,  [ ] or  permitted  assigns,  is
entitled to  purchase,  subject to the  provisions  of this Series C  Redeemable
Common Stock Purchase Warrant (the "Warrant"), from U.S. ENERGY SYSTEMS, INC., a
Delaware  corporation  (the  "Company"),  at an  exercise  price of Six  Dollars
($6.00) per share, [ ] ( ) shares of Common Stock,  par value $.01 per share, of
the Company  (the "Common  Stock") at any time during the period (the  "Exercise
Period") commencing as of [the Effective Date], and ending at 5:00 p.m. New York
City time, [five years after the Effective Date]. The number of shares of Common
Stock to be received  upon the exercise of this Warrant and the price to be paid
for a share of Common Stock may be adjusted from time to time as hereinafter set
forth.  The  shares of Common  Stock  deliverable  upon  such  exercise,  and as
adjusted from time to time, are  hereinafter  sometimes  referred to as "Warrant
Shares,"  and the  exercise  price for the  purchase of a share of Common  Stock
pursuant to this Warrant in effect at any time and as adjusted from time to time
is hereby referred to as the "Exercise Price". This Warrant is one of the Series
C Redeemable  Common Stock Warrants  issued pursuant to an Agreement and Plan of
Merger  dated as of  November  28,  2000 by and  among  the  Company,  USE Zapco
Aquisition Corporation and Zahren Alternative Power Corporation.

                  1. EXERCISE OF WARRANT.  Except as otherwise  provided herein,
this  Warrant  may be  exercised  in whole at any time,  or in part from time to
time,  during the Exercise  Period by presentation  and surrender  hereof to the
Company at its principal  office,  or at the office of its stock transfer agent,
if any, with the Purchase Form annexed  hereto as Exhibit A duly executed and by
paying in full, in lawful money of the United States,  in cash,  certified check
or bank draft payable to the order of the Company,  the Exercise  Price for each
full share of Common Stock as to which the Warrant is exercised  and any and all
applicable  taxes  due in  connection  with the  exercise  of the  Warrant,  the
exchange  of the Warrant for the Common  Stock,  and the  issuance of the Common
Stock. If this Warrant should be exercised in part only, the Company shall, upon
surrender  of this Warrant for  cancellation,  execute and deliver a new Warrant

<PAGE>


evidencing the rights of the Registered  Holder (as defined)  hereof to purchase
the balance of the shares purchasable hereunder.  Upon receipt by the Company of
this  Warrant and the  Exercise  Price  therefor at its office,  or by the stock
transfer  agent of the Company at its office,  in proper form for exercise,  the
Registered Holder shall, except as otherwise provided by Section 9(b) herein, be
deemed to be the holder of record of the shares of Common  Stock  issuable  upon
such exercise provided, that if the date of such surrender and payment is a date
when the stock  transfer  books of the Company are closed,  such person shall be
deemed to have  become  the  Registered  Holder  of such  shares at the close of
business on the next succeeding date on which the stock transfer books are open.

                  2. VALID ISSUANCE.  All shares of Common Stock issued upon the
proper  exercise of this  Warrant in  conformity  with the terms hereof shall be
validly issued, fully paid and non-assessable.

                  3. RESERVATION OF COMMON STOCK; LISTING OF SHARES. The Company
hereby agrees that: (a) at all times there shall be reserved for issuance and/or
delivery upon exercise of this Warrant such number of shares of its Common Stock
as shall be required for issuance and delivery  upon  exercise of this  Warrant;
and (b) in the event the shares of the Company's Common Stock are included on an
Exchange (as defined), it shall cause the Warrant Shares to be so listed.

                  4.       FRACTIONAL SHARES.

                           (a) The  Company shall not  be  required to  issue
fractional  shares upon exercise  of this Warrant.  If upon exercise  of  this
Warrant the  Company would  be required to  issue a fractional number of shares,
the Company shall, in lieu thereof,  pay to the Holder an amount  in cash equal
to such fraction  multiplied by the current Market Price Per Share (as defined),
as of the last  business  day prior  to the date of exercise  of this Warrant.

                           (b) As used herein, the term "Market Price Per Share"
on any date shall mean the closing  price per share of the Common  Stock for the
trading  day  immediately preceding  such date. The closing price  for each such
day shall be the last sale price or,  in  case no such sale  takes place on such
day,  the  average of the closing  bid and asked  prices, in  either case on the
principal  securities exchange (including any automated system of quotation) (an
"Exchange") on which the Common Stock is listed or admitted for trading,  or, if
not so listed on an Exchange, the average of the closing bid and asked prices as
furnished by  two members of the National  Association  of  Securities  Dealers,
Inc. selected from time to time by the Company for that purpose. If such bid and
asked prices are not available,  then "Market Price Per Share" shall be the fair
market value of the Company's Common Stock as determined  in good  faith by  the
Board of Directors of the Company.

                  5.  EXCHANGE,  TRANSFER,  ASSIGNMENT OR LOSS OF WARRANT.  This
Warrant  is  exchangeable,  without  expense,  at the  option of the  Registered
Holder,  upon  presentation and surrender hereof to the Company or at the office
of  its  stock  transfer   agent,  if  any,  for  other  warrants  of  different
denominations  entitling  the  Registered  Holder  thereof  to  purchase  in the

<PAGE>

aggregate  the same  number of shares of  Common  Stock  purchasable  hereunder.
Subject to the  provisions of Section 9 of this Warrant,  upon surrender of this
Warrant to the  Company or at the office of its stock  transfer  agent,  if any,
with the  Assignment  Form annexed  hereto as Exhibit A duly  executed and funds
sufficient to pay any transfer tax, the Company shall,  without charge,  execute
and deliver a new Warrant in the name of the assignee  named in such  instrument
of assignment and this Warrant shall  promptly be canceled.  This Warrant may be
divided or  combined  with  other  Warrants  which  carry the same  rights  upon
presentation  hereof at the office of the  Company or at the office of its stock
transfer agent, if any,  together with a written notice specifying the names and
denominations  in  which  new  Warrants  are  to be  issued  and  signed  by the
Registered  Holder  hereof.  The term  "Warrant"  as used  herein  includes  any
Warrants  into which this Warrant may be divided or  exchanged.  Upon receipt by
the  Company  of  evidence  reasonably  satisfactory  to it of the loss,  theft,
destruction  or mutilation of this Warrant,  and (in the case of loss,  theft or
destruction) of reasonably satisfactory indemnification,  and upon surrender and
cancellation of this Warrant, if mutilated, the Company will execute and deliver
a new Warrant of like tenor and date.

                  6. RIGHTS OF THE HOLDER. The holder of this Warrant shall not,
by virtue of this  Warrant,  be entitled to any rights of a  stockholder  in the
Company,  either at law or equity,  and the rights of the holder are  limited to
those  expressed  in the  Warrant  and are not  enforceable  against the Company
except to the extent set forth herein.

                  7.  ANTIDILUTION  ADJUSTMENT  OF NUMBER OF WARRANT  SHARES AND
EXERCISE PRICE; OTHER RECLASSIFICATIONS, REORGANIZATIONS OR MERGERS.

                           (a)In case  the Company  shall (i) pay  a dividend or
make a  distribution  on its  shares of  Common Stock in shares of Common Stock,
(ii)  split, subdivide or reclassify its outstanding Common Stock into a greater
number of shares or (iii) combine or  reclassify  its  outstanding  Common Stock
into a smaller  number of shares,  then the  number of  Warrant  Shares issuable
upon exercise of this Warrant, and the Exercise Price per share in effect at the
time of the  record date  for such dividend or  distribution or at the effective
date  of  such split, subdivision, combination or reclassification,  shall be
proportionately adjusted  so that if this Warrant is exercised  after such date,
the  Registered  Holder shall  be  entitled  to  receive  for the same aggregate
purchase  price, the aggregate number and kind of shares which,  if this Warrant
had been  exercised immediately prior to such time, such Registered Holder would
have  owned  after giving  effect to  such  dividend or  distribution,  split,
subdivision,  combination or  reclassification.  Such  adjustments shall be made
successively  whenever any event listed in this Section 7 shall occur. All price
calculations  under this  Section 7 shall be made  to the nearest whole cent and
share  adjustments  to the nearest share.

                           (b) If after  the  date hereof  any  capital
reorganization  or reclassification of  the Common  Stock  of  the Company,  or
consolidation or merger of the Company with or into another corporation,  or the
sale of all or substantially all of its assets to another  corporation  or other
similar event  (collectively  referred to as a "Transaction") shall be effected,
then,  as a condition  of such  Transaction, lawful and fair provision  shall be

<PAGE>

made whereby  the  Registered  Holder of this Warrant shall  thereafter have the
right  thereafter by exercising this Warrant, to purchase (in lieu of purchasing
the shares of Common  Stock of the Company immediately  theretofore  purchasable
and receivable upon the exercise of this Warrant), the kind and amount of shares
of stock, securities,  or assets receivable upon such Transaction by a holder of
the number of  shares of  Common Stock  which might  have been  purchased  upon
exercise of this Warrant  immediately prior to such Transaction.  In such event,
appropriate  provision shall be made with  respect to the  rights and  interests
of the  Registered  Holder of this Warrant to the end that the provisions hereof
(including,  without  limitation, provisions  for  adjustments  of the Exercise
Price and of the number of shares purchasable upon the exercise of this Warrant)
shall  thereafter be  applicable, as nearly  as may be, to  any  share of stock,
securities,  or assets  thereafter deliverable  upon the  exercise  hereof.  The
Company  shall not effect any such Transaction unless prior to the consummation
thereof  the  successor corporation (if  other than  the Company) resulting from
such Transaction,  or the corporation purchasing such  assets,  shall assume the
obligations  to  deliver  to  the Registered  Holder of this Warrant such shares
of stock,  securities,  or  assets which, in  accordance with  the  foregoing
provisions,  such holder may be entitled to purchase.

                  8. NOTICES OF CHANGE IN WARRANT.  Upon every adjustment of the
Exercise Price or the number of shares issuable on exercise of this Warrant, the
Company  shall give  written  notice  thereof to the  Registered  Holder of this
Warrant,  which  notice  shall  state the  Exercise  Price  resulting  from such
adjustment  and the  increase  or  decrease,  if any,  in the  number  of shares
purchasable  at such price upon the  exercise  of a  Warrant,  setting  forth in
reasonable  detail  the  method of  calculation  and the facts  upon  which such
calculation is based.  Upon the occurrence of any event  specified in Section 7,
then, in any such event, the Company shall give written notice to the Registered
Holder of this  Warrant  of the  record  date for such  dividend,  distribution,
split, reclassification or recombination,  or the effective date of Transaction.
Such notice  shall also specify the date as of which the holders of Common Stock
of  record   shall   participate   in  such   dividend,   distribution,   split,
reclassification or recombination, or shall be entitled to exchange their Common
Stock for stock,  securities,  or other assets  deliverable  upon a Transaction.
Failure  to give such  notice,  or any  defect  therein,  shall not  affect  the
legality or validity of such event.

                  9.       COMPLIANCE WITH THE SECURITIES ACT OF 1933.

                           (a)      This Warrant or  the Warrant Shares  or any
other security issued or issuable upon exercise of this Warrant may not  be sold
or otherwise disposed of except as follows:

                                    (i)     to a person who, in the opinion of
counsel reasonably acceptable the Company,  is a person to whom this  Warrant or
Warrant  Shares  may  legally be transferred  without   registration and without
the  delivery  of  a  current prospectus  under  the Act with  respect  thereto,
and  against receipt  of an  agreement of  such person  to  comply  with  the
obligations  of the holder of this Warrant which agreement  shall be reasonably
satisfactory in form and substance to the Company; or

<PAGE>

                                    (ii)  to  any  person  upon  delivery  of  a
prospectus then meeting the requirements of the Act relating to such securities
and the offering thereof for such sale or disposition.

                           (b) Notwithstanding anything to the contrary herein,
the  Company  shall  not be  obligated to deliver any securities  issuable  on
exercise  of  this  Warrant unless  the  issuance  of such securities  has  been
registered  under the  Act or, in  the  opinion of counsel to the Company,  the
issuance is exempt from the registration requirements of the Act and applicable
state  securities laws. This  Warrant may not  be  exercised by, nor  may  any
securities be issued to, any Registered  Holder or any other person in any state
in which such exercise would be unlawful.

                  10.      REDEMPTION

                           (a) After the first anniversary date of the Effective
Date, this Warrant may  be redeemed,  at the option of  the Company,  if all the
other outstanding  Series C Redeemable Common Stock  Purchase Warrants are  also
contemporaneously  redeemed, at any time, at  the office of the  Company or  its
stock transfer agent, upon  the notice  referred  to in  Section  10(b),  at the
price of $.001 per  Warrant Share (the "Redemption  Price"),  provided that  the
average of the last reported sales prices of the Common Stock  for  a  period of
twenty (20) consecutive trading  days ending on the  third  trading day prior to
the date on which notice of redemption is  given is at least one hundred twenty-
five  (125%)  percent  of the then effective Exercise Price of the Warrant.

                           (b) In the event the  Company  shall  elect to redeem
all of the outstanding Series C Redeemable Common Stock Purchase Warrants,   the
Company shall fix  a  date for  the redemption.  Notice  of redemption  shall be
mailed by first class mail,  postage prepaid,  by the Company or the  Company's
agent at its direction not less that fifteen  (15)  business  days  prior to the
date  fixed  for  redemption  to the  Registered Holder  of  this Warrant  to be
redeemed at  the  Registered Holder's last  address  as it shall  appear on  the
Warrant  Register  (as  defined).  Any  notice  mailed  in  the manner  herein
provided shall be conclusively presumed to have been duly give  whether  or not
the  Registered  Holder of this  Warrant  shall  have received such notice.

                           (c) This Warrant may be exercised in accordance  with
Section 1 hereof at any time  after notice of  redemption  shall have been given
by the  Company  pursuant to Section  10(b) and  prior to the  close of business
on the  date  fixed  for redemption.  After the redemption date,  the Registered
Holder of this Warrant shall  have no  further rights  except  to receive,  upon
surrender of this Warrant, the Redemption Price.

                  11.      MISCELLANEOUS.

                           (a)      All communications provided for herein shall
be sent, except as may be otherwise specifically provided, by registered or
certified mail: if  to  the Registered Holder of  this Warrant, to  the address
shown on the books of the Company; and if to the Company, to U.S. Energy Systems
, Inc., 515 N.  Flagler Drive, Suite 702,  West Palm  Beach, Florida  33401,
Attention: President, or to  such  other address  as the Company may advise the
Registered Holder  of  this Warrant in writing.  Notices shall  be  deemed given
when mailed.

<PAGE>

                           (b)      The provisions of this Warrant shall in all
respects  be  constructed according to, and the  rights and  liabilities  of the
parties hereto shall in all respects be  governed  by, the laws of the  State of
Delaware,  without  regard to such state's choice of law rules.

                           (c)      The Company shall maintain books ("Warrant
Register") for the  registration of original  issuance and the  registration  of
transfer of the Warrants. Upon the initial issuance of the Warrants, the Company
shall issue and  register  the Warrants in the names of the holders thereof.

                           (d)      Prior to due presentment for registration of
transfer of this Warrant, the Company may deem and treat  the  person  in  whose
name  this  Warrant  shall be registered  upon the Warrant Register ("Registered
Holder"),  as the absolute owner of such Warrant and of each Warrant represented
thereby  (notwithstanding  any  notation of  ownership  or  other writing on the
Warrant  certificate  made by anyone other than the Company,  for the purpose of
any exercise thereof, and for all other  purposes,  and the Company shall not be
affected by any notice to the contrary).

Dated:  [Effective Date]


                                      U.S. ENERGY SYSTEMS, INC.


                                      By:__________________________
                                         Goran Mornhed, President

<PAGE>


                                                                Exhibit A

                                  PURCHASE FORM

                                                            Dated_______ , 20__

         The  undersigned  hereby irrevocably  elects  to exercise  the  within
Warrant  to  the  extent of purchasing shares of Common Stock and hereby  makes
payment of _________ in payment of the actual exercise price thereof.

                     INSTRUCTIONS FOR REGISTRATION OF STOCK

Name___________________________________
         (Please typewrite or print in block letters)

Signature________________________________


                                 ASSIGNMENT FORM

                  FOR VALUE RECEIVED,
hereby sells, assigns and transfer unto

Name___________________________________
    (Please typewrite or print in block letters)

Address_________________________________

Social Security or Employer Identification No.__________
the right to purchase Common Stock  represented by this Warrant to the extent of
_____shares  as to which such right is exercisable  and does hereby  irrevocably
constitute and appoint  ________________  Attorney,  to transfer the same on the
books of the Company with full power of substitution in the premises.

Dated:___________, 20__

Signature_____________

Signature Guaranteed


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