Sustainable Energy Secures $7.6 Million Private Placement

Doughty Hanson Technology Ventures Provides $4.5 Million Lead Investment

CALGARY, ALBERTA--(Marketwire - May 8, 2009) - Sustainable Energy Technologies Ltd (TSX VENTURE:STG) ("Sustainable Energy" or the "Company"), a developer of breakthrough solar inverter technology, announces that it has secured a minimum $7.6 million in financing to support the launch of its next generation "SUNERGY II" solar inverter platform in Europe and North America.

Doughty Hanson, one of Europe's leading venture capital investors, has led the funding round with an initial $4.5 million investment in Sustainable Energy, with an option to invest a further $1.5 million over the next six months. Other investors have invested a further $3.1 million, and the Company expects to secure up to an additional $1.3 million by May 15, 2009.

Solar photovoltaic ("PV") inverters convert the direct current ("DC") power generated by solar PV modules into alternating current ("AC") power required by the power grid. SUNERGY II is the only inverter that allows grid connected solar PV systems to be designed using a "massively parallel" architecture with electrical conversion efficiencies that meet or exceed industry leaders.

Conventional inverters require solar panels to be installed using a "series" architecture, where any reduction in power from one panel results in reduced power from all the panels. The impacts of partial shading caused by normal building congestion (e.g. chimneys, railings, telecommunications towers, etc) and of different panel orientations to the sun cause significant reductions in power yield and require considerable design expense.

The massively parallel approach of SUNERGY II enables each module to operate at its optimum level, significantly increasing total energy harvest from the system. In addition, the parallel architecture allows higher utilization of available rooftop space at a lower design cost.

George Powlick, Partner of Doughty Hanson Technology Ventures, who will join the Board of the Company comments: "We've been studying the limitations of conventional serial inverter technologies for more than two years and believe that the parallel system architecture has the potential to accelerate solar PV as a mainstream power source. Sustainable Energy's approach is the only one we have seen with the ability to increase the energy output of a solar PV system while bringing down costs at the same time."

"Sustainable Energy has the unique combination that we look for in a potential investment: differentiated technology, a low manufactured cost on which to build a world class company and an ambitious and experienced management team. The company is well placed to consolidate its strong market position, and we look forward to supporting the management in achieving its ambitious growth strategy for the future." added Powlick.

Michael Carten, President & CEO of Sustainable Energy added:

"Sustainable Energy is at an inflection point in its development. Changing market dynamics have created an unparalleled opportunity for our technologies and products, which must be seized now. This investment will enable us to do just that; and to build Sustainable Energy into one of the leading inverter companies serving the needs of the global solar industry."

"The value of our partnership with Doughty Hanson is substantial. As an experienced investor in the solar PV industry, their participation is an important validation of our technology's potential. Their commitment of capital and management resources enhances our abilities to create the key strategic relationships and to attract the people Sustainable Energy will need to execute on our business plan." concluded Carten.

Financing Terms

Doughty Hanson has invested $4.5 million to acquire (i) 450,000 units ("Class A Units") each unit consisting of one (1) redeemable, 8%, voting, First Preferred Share Series 7 of the Company initially convertible into Common Shares of the Company at a rate of $0.15 per share (the "Convertible First Preferred Shares) and 28 warrants (Warrants) to acquire one voting or non-voting Common Share of the Company exercisable for a period of 4 years from the Closing Date at an exercise price of $0.30 per share and (ii) an option (the "Option") exercisable for a period of 6 months from the Closing Date to invest an additional $1.5 million for 10 million Common Shares of the Company. The full and complete terms of the Convertible First Preferred Shares will be filed on SEDAR and will be available at www.sedar.com.

The Warrants are exercisable for voting Common Shares unless at the time of exercise the holder of the Warrants would, following the exercise, have or be entitled to acquire more than 20% of the voting rights of Sustainable Energy. The shareholders of the Company will be asked to approve the exercise of Warrants for voting Common Share in all cases at the next Annual Meeting of Shareholders to be held on or about July 22, 2009. If such approval is not forthcoming the number of Warrants in the Class A Units will be increased to 33.

The Class A Units and Common Shares acquired by Doughty Hanson are subject to a lock up agreement prohibiting the sale or other disposition of such securities for a period of one year from the Closing Date. The Directors of the Company are also subject to a similar one-year lock up agreement while they remain directors.

Doughty Hanson acquires the right to designate a representative to the Board of Directors of the Company which shall be set at 5 directors at the next Annual Shareholders Meeting, and, if the Board of Directors is expanded to 7, the right to nominate one outside director who shall be independent of Doughty Hanson. Doughty Hanson and the Company have entered into an investor rights agreement that will give Doughty Hanson information and governance rights as well as registration rights.

Sustainable Energy will issue, as a brokered private placement, up to 440,000 units ("Class B Units"), each Class B Unit consisting of one Convertible First Preferred Share and 22 Warrants for a total consideration of up to $4.4 million. As of this date 313,500 Class B Units have been issued for gross proceeds of $3.14 million. Doughty Hanson holds approximately 19% of voting rights of Sustainable Energy.

The Class A Units, the Class B Units, the Option and the securities comprising such instruments are subject to a four month hold period.

About Doughty Hanson: Doughty Hanson (www.doughtyhanson.com) is one of Europe's most successful independent private equity firms. Since 1985, Doughty Hanson has undertaken more than 118 investments with an aggregate acquisition value in excess of EUR 28 billion. Doughty Hanson employs over 50 investment professionals of 15 nationalities, located in offices in London, San Francisco, Frankfurt, Madrid, Milan, Munich, Paris and Stockholm.

About Sustainable Energy: Based in Calgary, Canada, Sustainable (www.sustainableenergy.com) designs, manufactures and distributes power inverters for grid-connected solar PV systems. Advanced power inverters are a critical enabler of all modern solar PV power systems converting the direct current ("DC") power output of the solar PV modules into the high quality alternating current ("AC") power required by the power grid. Advanced power inverters also optimize the performance of the solar PV modules and maintain the integrity and safety of the interconnection with the power grid.

Sustainable Energy has developed and patented an inverter design which is a breakthrough in solar inverter technology. It is the only inverter design which allows grid connected solar PV systems to be designed using a "massively parallel" architecture with an industry standard form factor and with electrical conversion efficiencies that meet or exceed industry leaders.

Sustainable Energy's technologies are the subject of 9 patents issued by the US Patent Office with further patents pending.

Forward Looking Information

The reader is advised that some of the information herein may constitute forward-looking statements within the meaning assigned by National Instruments 51-102 and other relevant securities legislation. In particular, we include: statements concerning the impact of our technology on solar PV system performance; statements concerning the potential for sales in the markets we have entered and statements concerning the manufactured cost of our products. Forward-looking information is not a guarantee of future performance and involves a number of risks and uncertainties. Many factors could cause the Company's actual results, performance or achievements, or future events or developments, to differ materially from those expressed or implied by the forward-looking information. Readers are cautioned not to place undue reliance on forward-looking information, which speaks only as of the date hereof. The Company does not undertake any obligation to release publicly any revisions to forward-looking information contained herein to reflect events or circumstances that occur after the date hereof or to reflect the occurrence of unanticipated events, except as may be required under applicable securities laws.

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.