Wal-Mart, Westport and Mojave Desert Air District Partner to Reduce Emissions With LNG Trucks in Apple Valley, CA

Westport Innovations Inc. (TSX: WPT), a global leader in gaseous-fuelled power technologies, today announced that Wal-Mart Stores, Inc. will introduce four liquefied natural gas (LNG) fuelled Peterbilt 386 trucks into service at their distribution centre in Apple Valley, California.

The deployment will be supported in part by funding from the Mojave Desert Air Quality Management District's (MDAQMD) Mobile Source Emission Reductions Competitive Bidding Program.

Wal-Mart, which operates one of the nation's largest private fleets, announced its "Sustainability 360" program in 2007 which promotes a holistic approach to integrating sustainability throughout its business.

The objective of this project is to demonstrate the efficiency and significant emissions reduction benefits of Westport LNG fuel systems in heavy-duty trucks. The four trucks in this proposal will be used in Wal-Mart's over-the-road (OTR) goods distribution operations in the MDAQMD. The project will also demonstrate the effectiveness of Westport's commercially available technology and will work to grow the heavy-duty natural gas market.

"Our experience shows that by using natural gas, Westport's LNG fuel system can help Wal-Mart reduce their fleet vehicles' greenhouse gas emissions by some 20 per cent and NOx emissions by between 30 and 50 per cent over their diesel equivalents," said Michael Gallagher, president and chief operating officer of Westport. "This represents a significant milestone for Westport as we have been actively pursuing large private and commercial truck fleets. We are very proud to be given the opportunity to showcase Westport's innovative approach to commercial transportation with an environmental leader like Wal-Mart."

"Wal-Mart is careful to consider the civic and environmental impact its operations have in the communities it serves around the world," says Tim Yatsko, senior vice president of transportation at Wal-Mart. "We are continually looking for new, innovative ways to reduce the emissions of our fleet. This program will give us an opportunity to evaluate Westport's low-emissions solution in real-world operations."

John Wall, Vice President and Chief Technical Officer of Cummins Inc. added, "Cummins remains committed to supporting the integration of Westport's unique LNG fuel system with the Cummins ISX engine. We are confident that Wal-Mart will be impressed with the performance of the HPDI-equipped ISX and that it is the right complement to Cummins ISX clean diesel power in their demanding applications."

About Westport's LNG System for Heavy Duty Trucks

Westport's LNG system for heavy duty Class 8 trucks offers class-leading emissions, including lower greenhouse gas emissions than comparable diesel engines, and allows trucking fleets to move to lower-cost, domestically available natural gas and/or biogas. Based on the industry-leading Cummins ISX diesel engine with cooled EGR, the LNG version of the engine offers the same horsepower, torque, and efficiency as the base diesel engine rating it is replacing. The Cummins ISX unique dual overhead cam design delivers high performance and exceptional braking every mile. Variable Geometry Turbocharging produces quicker throttle response with less turbo "lag" for faster acceleration off the line and on highway on-ramps. Infinite adjustment provides the exact amount of boost needed at every engine speed. The 2007 Westport LNG system is available with 400 and 450 horsepower ratings and up to 1,750 lb-ft torque for heavy-duty port, goods distribution and other commercial truck applications. LNG fuel tanks can be configured to suit customer range requirements.

The Westport LNG system comprises LNG fuel tanks, proprietary Westport fuel injectors, cryogenic fuel pumps and associated electronic components to facilitate robust performance and reliable operation. The Westport LNG system is 2008 EPA and CARB certified to 0.8g/bhp-hr NOx and 0.01g/bhp-hr PM. Trucks are eligible for a federal tax credits in the United States and may be eligible for other state-specific emissions credits.

About Wal-Mart Stores, Inc. (NYSE: WMT)

Wal-Mart Stores, Inc. operates Wal-Mart discount stores, Supercenters, Neighborhood Markets and Sam's Club locations in the United States. The Company operates in Argentina, Brazil, Canada, China, Costa Rica, El Salvador, Guatemala, Honduras, Japan, Mexico, Nicaragua, Puerto Rico and the United Kingdom. The Company's securities are listed on the New York Stock Exchange under the symbol WMT. More information about Wal-Mart can be found by visiting www.walmartfacts.com. Online merchandise sales are available at www.walmart.com.

About Westport Innovations Inc.

Westport Innovations Inc. is a leading global supplier of proprietary solutions that allow engines to operate on clean-burning fuels such as compressed natural gas (CNG), liquefied natural gas (LNG), hydrogen and biofuels such as landfill gas. Cummins Westport Inc., Westport's joint venture with Cummins Inc., manufactures and sells the world's broadest range of low-emissions alternative fuel engines for commercial transportation applications such as trucks and buses. BTIC Westport Inc., Westport's joint venture with Beijing Tianhai Industry Co. Ltd., manufactures and sells LNG fuel tanks for vehicles. www.westport.com.

Note: This document contains forward-looking statements about Westport's business, operations, technology development or the environment in which it operates, which are based on Westport's estimates, forecasts and projections. These statements are not guarantees of future performance and involve risks and uncertainties that are difficult to predict, or are beyond Westport's control. Consequently, readers should not place any undue reliance on such forward-looking statements. In addition, these forward-looking statements relate to the date on which they are made. Westport disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.