Orion Energy Systems: Wisconsin-based Orion CEO to ring Nasdaq exchange opening bell on Earth Day

Energy management company helping customers reduce negative impact on environment and save on energy costs

MANITOWOC, Wis. — April 21, 2009 — Neal Verfuerth, president and CEO of Orion Energy Systems Inc. (Nasdaq: OESX), will ring the opening bell at the Nasdaq stock exchange on Wednesday, April 22, to celebrate Earth Day.

Verfuerth, surrounded by key management of the growing energy management company, will ring the Nasdaq opening bell at 8:30 a.m. CDT at Nasdaq MarketSite in Times Square at West 43rd Street and Broadway in New York City.

The bell ringing ceremony will be broadcast live on webcam starting at 8:15 a.m. CDT at http://www.oesx.com.

Orion is a leading power technology enterprise that designs, manufactures and implements energy management systems, consisting primarily of high-performance, energy-efficient lighting systems, controls and direct renewable products for commercial and industrial customers.

“We’re honored to be kicking off Earth Day at the Nasdaq exchange for the second year in a row,” Verfuerth said. “Our mission of reducing greenhouse gas emissions fits in well with Earth Day. Through our technology, we’ve helped more than 4,000 customers displace more than 4.3 million tons of carbon dioxide and saving them more than $500 million in energy costs.”

Orion’s technology helps the U.S. overcome electrical grid challenges through permanent distributed load reduction by deploying its integrated system in commercial and industrial facilities. Orion’s integrated system, which includes its high-intensity fluorescent lighting platform, wireless controls and Apollo® Solar Light Pipes, permanently reduces energy consumption, freeing electrical capacity for constrained utilities, and decreasing greenhouse gases, which are the byproduct of electricity generation.

Recently, Orion’s innovation and technology won the praise of President Barack Obama, who applauded Orion in a White House speech promoting clean energy, the creation of green collar jobs and the importance of energy efficiency. Obama challenged Orion and other clean energy companies to “mount a historic effort to end once and for all our dependence on foreign oil.”

Orion has rung the bell at Nasdaq twice before, on Earth Day, April 22, 2008, and on Dec. 31, 2007.

In addition to ringing the opening bell at the Nasdaq stock exchange on Earth Day, Orion on Wednesday will officially unveil its state-of-the-art technology center to more than 500 invited guests and the media. Wisconsin Gov. Jim Doyle is scheduled to speak at the event.

The media is invited to cover the event and Doyle’s speech at 2 p.m. For more information about covering the open house, contact Linda Diedrich, Orion’s director of corporate communications at (920) 482-1988, by cell phone at (920) 918-2643 or at ljd@oes1.com.

Orion has deployed its energy management systems in 4,387 facilities across North America. Since 2001, Orion technology has displaced more than 423 megawatts, saving customers more than $514 million and reducing indirect carbon dioxide emissions by 4.3 million tons. Orion’s technology was recently internationally recognized with a Platts Global Energy Award for the single most innovative and sustainable green technology of 2008.

Webcast: A live webcast of the NASDAQ Opening Bell will be available at: http://www.nasdaq.com/reference/marketsite_about.stm.

Photos: To obtain a hi-resolution photograph of the Market Open, please go to http://www.nasdaq.com/reference/marketsite_events.stm and click on the market open of your choice.

Orion Energy Systems Inc. (Nasdaq: OESX) is a leading power technology enterprise that designs, manufactures and implements energy management systems, consisting primarily of high-performance, energy-efficient lighting systems, controls and related services for commercial and industrial customers without compromising their quantity or quality of light. For more information, visit http://www.oesx.com.

Media Contacts

Linda Diedrich

Director Corporate Communications

(920) 482-1988

ljd@oes1.com

NASDAQ MarketSite:

Robert Madden

(646) 441-5045 (office)

Robert.Madden@NASDAQOMX.com