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                                                                    Exhibit 10.8

PROMISSORY NOTE


Cdn. $50,000                                                     August 10, 1999
                                               Burnaby, British Columbia, Canada

FOR VALUE RECEIVED, the receipt and sufficiency of which is hereby acknowledged,
Clean Energy Combustion Systems, Inc. and Clean Energy Technologies (Canada)
Inc. (collectively, the "Maker"), hereby jointly and severally promise to pay to
R. Dirk Stinson, or order (the "Holder"), at such address as the Holder may from
time-to-time designate by written notice to the Maker, the principal sum
hereinbelow described (the "Principal Amount"), together with interest thereon,
in the manner and at the times herebelow provided and subject to the terms and
conditions herebelow described.

1.   PRINCIPAL AMOUNT

     The Principal Amount means the sum of fifty thousand Canadian dollars (Cdn.
     $50,000), which has been advanced by the Holder to the Maker
     contemporaneously with or prior to the date of this Note, plus any such
     additional amounts as the Holder may in the future advance from time-to-
     time to the Maker.

2.   INTEREST

     Interest on the Principal Amount from time-to-time remaining unpaid shall
     accrue from the date of any advances to the Maker under this Note at the
     rate of Royal Bank Prime Rate plus 2% per annum. Interest shall be computed
     on the basis of a three hundred sixty (360) day year and a thirty (30) day
     month.

3.   PAYMENT ON PRINCIPAL AND INTEREST

     Subject to paragraphs 3 and 5, the Principal Amount and all interest and
     other indebtedness under this Note shall be due and payable at such time as
     the Maker raises the sum of seven hundred fifty thousand Canadian dollars
     (Cdn. $750,000) through equity, debt or joint-venture financing or product
     revenues, or any combination thereof, but in any event by August 10, 2000.

     Payments of any amount required hereunder shall be made solely in lawful
     money of Canada, and shall be credited first against other indebtedness
     under this Note, if any, next against accrued but unpaid interest, if any,
     and with the balance of such payment applied against the unpaid balance of
     the Principal Amount.

     The Maker reserves the right to prepay any portion of the Principal Amount
     in whole or in part (in either case with any accrued and unpaid interest
     through the date of prepayment plus any other amounts due under this Note)
     without prepayment penalty or premium or discount.

     Whenever any payment required under the terms of this Note shall be stated
     to be due on a day other than a business day, such payment shall be made on
     the next succeeding business day, and such extension of time shall in such
     case be included in the computation of payment of interest.

4.   ACCELERATION UPON DEFAULT

     At the option of the Holder, all or any part of the indebtedness of the
     Maker hereunder shall immediately become due and payable, irrespective of
     any agreed maturity, upon the happening of any of the following events of
     default:

     (a)  If the Maker shall make an assignment for the benefit of creditors;

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     (b)  If a custodian, trustee, receiver, or agent is appointed or takes
          possession of substantially all of the property of the Maker;

     (c)  If the Maker becomes insolvent;

     (d)  If the Maker shall file a petition of bankruptcy, or apply to any
          tribunal for appointment of a custodian, trustee, receiver, or agent
          of the Maker, or commence any proceeding related to the Maker under
          any bankruptcy or reorganization statute, or under any arrangement,
          insolvency, readjustment of debt, dissolution, or liquidation law of
          any jurisdiction, whether now or hereafter in effect;

     (e)  If any petition is filed against the Maker under any bankruptcy or
          reorganization statute and either (1) the relief is ordered by the
          applicable jurisdiction against the Maker under the applicable
          bankruptcy or reorganization statute, or (2) such petition is not
          dismissed by the applicable jurisdiction within thirty (30) days of
          the date of filing; or

     (f)  If any attachment, execution, or other writ is levied on substantially
          all of the assets of the Maker and remains in effect for more than
          fifteen (15) days.

5.   CONVERSION OF NOTE INTO COMMON STOCK

     The Holder shall reserve the right at any time, in his sole discretion, to
     convert any portion of the Principal Amount and all interest and other
     indebtedness under this Note remaining unpaid into Clean Energy Combustion
     Systems, Inc. common stock at the conversion rate of two United States
     dollars (U.S. $2.00) per one (1) share of common stock. The Maker shall
     afford the Holder five (5) business days' prior written notice relative to
     the Maker's intent to pay or prepay the Principal Amount or any portion
     thereof in order to allow the Holder to make the aforesaid election.

6.   PURCHASE OF PBC TECNOLOGY

     The Maker agrees that it shall not have the right to exercise its right to
     purchase the PBC Technology from 818879 Alberta Limited pursuant to the
     terms of that certain PBC Technology License dated March 5, 1999 unless and
     until all indebtedness under this Note shall be paid or converted into
     common stock pursuant to the terms of this Note.

7.   COLLECTION COSTS AND ATTORNEYS' FEES

     The Maker agrees to pay the Holder all costs and expenses, including
     reasonable attorneys' fees, actually paid or incurred by the Holder in
     connection with the collection or enforcement of this Note. In the event
     any party institutes or should the parties otherwise become a party to any
     action or proceeding in connection with the enforcement or interpretation
     or collection of this Note, or for damages by reason of any alleged breach
     of this Note or any provision hereof and/or any alleged breach, of any
     instrument securing payment of this Note or any provision thereof, or for a
     declaration of rights in connection with this Note and/or any instrument
     securing payment of this Note, or for any other relief, including equitable
     relief, in connection with this Note, the prevailing party in any such
     action or proceeding shall be entitled to receive from the non-prevailing
     party all costs and expenses including, without limitation, reasonable
     attorneys' and other fees actually incurred by the prevailing party in
     connection with such action or proceeding, and shall also be entitled to
     collect as damages those costs and expenses hereinabove described in the
     first sentenced of this section.

8.   NOTICE

     Any notice to the Maker provided for in this Note shall be given by
     personal delivery or by express mail, Federal Express, DHL or similar
     airborne/overnight delivery service, or by mailing

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     such notice by first class or certified mail, return receipt requested,
     addressed to the Maker at his or her address presently on the books of the
     Maker, or to such other address as the Maker may designate by written
     notice to the Holder. Any notice to the Holder shall be given by personal
     delivery or by express mail, Federal Express, DHL or similar
     airborne/overnight delivery service, or by mailing such notice by first
     class or certified mail, return receipt requested, addressed to the Holder
     at its present executive offices, or to such other address as may have been
     designated by written notice to the Maker. Mailed notices shall be deemed
     delivered and received three (3) days after deposit in accordance with this
     provision in the Canadian or, if applicable, United States mail.

9.   USURY COMPLIANCE

     All agreements between the Maker and the Holder are expressly limited, so
     that in no event or contingency whatsoever, whether by reason of the
     consideration given with respect to this Note, the acceleration of maturity
     of the unpaid Principal Amount and interest thereon, or otherwise, shall
     the amount paid or agreed to be paid to the Holder for the use,
     forbearance, or detention of the indebtedness which is the subject of this
     Note exceed the highest lawful rate permissible under the applicable usury
     laws. If, under any circumstances whatsoever, fulfillment of any provision
     of this Note after timely performance of such provision is due, shall
     involve transcending the limit of validity prescribed by law which a court
     of competent jurisdiction deems applicable, then ipso facto, the
     obligations to be fulfilled shall be reduced to the limit of such validity,
     and if, under any circumstances whatsoever, the Holder shall ever receive
     as interest an amount that exceeds the highest lawful rate, the amount that
     would be excessive interest shall be applied to the reduction of the unpaid
     Principal Amount and/or late charges under this Note and not to the payment
     of interest, or, if such excessive interest exceeds the unpaid balance of
     the Principal Amount and/or late charges under this Note, such excess shall
     be refunded to the Maker. This provision shall control every other
     provision of all agreements between the Maker and the Holder.

10.  GENERAL

     (A)  No Waiver of Holder's Rights. No delay or failure or act of commission
          or omission on the part of the Holder in exercising any rights under
          this including, without limitation, the Holder's right to accelerate,
          nor reinstatement of this Note by the Holder after such exercise,
          shall operate as a waiver of the Maker's right to exercise such right
          or of any other right under this Note or as a release of Maker, for
          the same default or any other default, except to the extent such
          waiver is in writing and signed by the Holder and then only to the
          extent specifically set forth in writing.

     (b)  Successors and Assigns. This Note and all of the covenants, promises
          and agreements contained in it shall be binding on and inure to the
          benefit of the respective legal and personal representatives, devises,
          heirs, successors, and assigns of the Maker and the Holder.

     (c)  Integration. This writing is intended by the parties to be an
          integrated and final expression of this Note and also is intended to
          be a complete and exclusive statement of the terms of that agreement.
          No course of prior dealing between the parties, no usage of trade, and
          no parole or extrinsic evidence of any nature shall be used to
          supplement, modify or vary any of the terms hereof. There are no
          conditions to the full effectiveness of this Note except as
          specifically provided herein.

     (d)  Invalidity. If any provision of this Note, or the application of it to
          any party or circumstance, is held to be invalid, the remainder of
          this Note, and the application of such provision to other parties or
          circumstances, shall not be affected thereby, the provisions of this
          Note being severable in any such instance.

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     (e)  Interpretation. This Note shall be governed by, interpreted under and
          construed and enforced in accordance with the laws of the Province of
          British Columbia, Canada applicable to contracts entered into in the
          Province of British Columbia, Canada, by residents of the Province of
          British Columbia, Canada, and intended to be performed entirely within
          the Province of British Columbia, Canada.

IN WITNESS WHEREOF, the Maker, intending to be legally bound hereby, has duly
executed this Note the day and year first above written.

MAKER:

Clean Energy Combustion Systems, Inc.        Clean Energy Technologies (Canada)
                                             Inc.



By:     /s/ J.P. Thuot                       By:     /s/ B.A. Sheahan
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