Burlington, MA, February 20, 2008 - InterGen announced today that it has executed a purchase agreement to acquire TransAlta Corporations 511 MW Mexico portfolio, consisting of two operating power plants, the 252 MW Campeche facility and the 259 MW Chihuahua facility. The value of the transaction is $303.5 million, and will be funded by a combination of InterGen equity and non-recourse debt.

Campeche is located at Palizada in the State of Campeche in the Yucatan Peninsula, and Chihuahua is located in the highly industrial border region of Juarez, just south of the U.S./Mexico border. Both combined-cycle projects began operations in 2003 and are fully contracted with 25-year power purchase agreements with Comisi?n Federal de Electricidad, the Mexican national utility. They were bid and developed under CFE's successful IPP program, which has awarded 22 PPAs since 1997, including InterGen's La Rosita and Baj?o projects.

"We are delighted to be acquiring TransAlta's Mexican generation portfolio, and to consequently expand our strong platform in Mexico", said Neil H. Smith, InterGen President & Chief Executive Officer. "These facilities are a good fit with InterGen's current portfolio and demonstrate our long-term commitment to Mexico."

InterGen is a global power generation firm with nine power plants representing an equity share of 5,235 MW of production capacity. InterGen plants and development projects are located in the UK, the Netherlands, Mexico, the Philippines and Australia. Additionally, InterGen's 428 MW Rijnmond II project, located in the Netherlands, is currently under construction. InterGen is jointly owned by the Ontario Teachers' Pension Plan and AIG Highstar Capital II, L.P.

For more information on InterGen, visit www.intergen.com.

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