GreenMan Technologies Subsidiary Successfully Completes Test Trials in Australia

LYNNFIELD, MA--(Marketwire - Jun 1, 2011) - GreenMan Technologies, Inc. (OTCQB: GMTI) (PINKSHEETS: GMTI) announced that its American Power Group, Inc. subsidiary ("APG") has successfully completed heavy-duty truck test trials in Australia utilizing APG's patented Dual Fuel System operating on diesel fuel and liquefied natural gas ("LNG"). Last October, APG signed an agreement to carry out a test trial with Wesfarmers LNG Pty Ltd, a subsidiary of Kleenheat Gas, for the conversion of two 500+ horsepower heavy-duty diesel trucks to APG's patented Dual Fuel System.

Kleenheat Gas extracts, distributes and markets liquefied petroleum gas (LPG), and is a leading provider of gas services to residential, commercial, industrial, rural and automotive markets across Australia. Through its subsidiary Wesfarmers LNG Pty Ltd which trades as EVOL LNG, it is the leading provider of LNG to the heavy duty vehicle and remote power generation markets in Australia.

APG's dual fuel system converts diesel engines and diesel generators to function more efficiently and at a lower operating cost, by seamlessly displacing 40% to 60% of the normal diesel fuel consumption with CNG, LNG, well-head gas or bio-methane. APG's system is non-invasive to the OEM engine and operates within all OEM performance controls with the flexibility to return to 100% diesel operation at any time. APG's dual fuel conversion and emissions reduction systems can help users achieve their sustainability goals through lower carbon monoxide, nitrogen oxide, and particulate matter emissions. In addition, the introduction of natural gas through APG's dual fuel system does not impact diesel engine power or pulling torque and will assist in extending the engine's oil life as natural gas is a cleaner burning fuel compared to diesel.

Lyle Jensen, GreenMan's President and Chief Executive Officer, stated, "Passing the Australian test trials is a major performance milestone for APG. We are extremely pleased to report that all fuel displacement, reliability up-time, and emission results met or exceeded EVOL LNG's performance criteria established at the beginning of the trials. The Australian Outback super-highway is one of the world's toughest driving environments and the APG Dual Fuel System performed exceptionally well on high-horsepower diesel engines where natural gas solutions are not yet available from many dedicated alternative fuel system providers. In Australia, we have added 'durability performance' to the economic and environmental benefits of our dual fuel technology."

Commenting on the trials, Kleenheat Gas General Manager Graham Smith said: "During our field tests, we were impressed with the reliability of APG's Dual Fuel System and we eagerly await APG finalizing its offering for the Australian heavy duty market conditions. EVOL LNG is leading the development of LNG as a viable long term alternative fuel to diesel in the Australian heavy-duty vehicle, industrial, and remote power generation markets. We are proud to be at the forefront of how LNG is changing the direction of road transport in Australia."

Mr. Jensen concluded, "We believe that a significant number of Australian trucks and power generators can benefit from APG's dual fuel technology."

About GreenMan Technologies
GreenMan's two alternative energy subsidiaries, American Power Group, Inc. ("APG") and APG International, Inc. ("APGI"), provide a cost-effective patented dual fuel conversion technology for diesel engines and diesel generators. APG's dual fuel technology is a unique non-invasive energy enhancement system that converts existing diesel engines into more efficient and environmentally friendly engines that have the flexibility to run on: 1) diesel fuel and compressed natural gas ("CNG"); 2) diesel fuel and liquid natural gas ("LNG"); 3) diesel fuel and well-head gas); and 4) diesel fuel and bio-methane with the flexibility to return to 100% diesel fuel operation at any time. The proprietary technology seamlessly displaces 40% to 60% of the normal diesel fuel consumption and the energized fuel balance is maintained with a proprietary electronic controller system ensuring the engines operate to Original Equipment Manufacturers' ("OEM") specified temperatures and pressures. Installation on a wide variety of engine models and end-market applications requires no engine modification unlike the more expensive invasive alternative fuel systems in the market. See additional information at www.greenman.biz and www.americanpowergroupinc.com.

About Kleenheat Gas
Kleenheat Gas is part of Wesfarmers Chemicals, Energy & Fertilisers which operates chemical, gas, remote power generation and fertiliser businesses servicing customers domestically and internationally. Wesfarmers Chemicals, Energy & Fertilisers is a division of the diversified conglomerate Wesfarmers Limited, one of Australia's largest publicly listed companies achieving AUD$50 billion in annual revenue and employing more than 200,000 employees in Australia and New Zealand. Please see: www.kleenheatgas.com.au for further information regarding Kleenheat Gas, www.evollng.com.au for further information regarding EVOL LNG, and www.wescef.com.au for further information regarding the Wesfarmers Chemical, Energy & Fertilisers group of businesses.

"Safe Harbor" Statement: Under the Private Securities Litigation Reform Act
With the exception of the historical information contained in this news release, the matters described herein contain "forward-looking" statements that involve risks and uncertainties that may individually or collectively impact the matters herein described, including but not limited to the fact that we have sold the tire recycling operations which have historically generated substantially all our revenue and that we will be prohibited from competing in that business on a regional basis until 2013; the risk that we may not be able to increase the revenue or improve the operating results of our American Power Group division; the risk that we may not be able to return to sustained profitability; the risk that we may not be able to secure additional funding necessary to grow our business, on acceptable terms or at all; the risk that if we have to sell securities in order to obtain financing, the rights of our current stockholders may be adversely affected; the risk that we may not be able to increase the demand for our products and services; the risk that we may not be able to adequately protect our intellectual property; and risks of possible adverse effects of economic, governmental, seasonal and/or other factors outside the control of the Company, which are detailed from time to time in the Company's SEC reports, including our Annual Report on Form 10-K for the fiscal year ended September 30, 2010. The Company disclaims any intent or obligation to update these "forward-looking" statements