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Three Mile Island (TMI) Unit 1, located in Londonderry Township, Dauphin County, in Pennsylvania, generates 852 megawatts of clean, safe and reliable electricity for more than 800,000 homes.

In 2009, Three Mile Island Unit 1 received a 20 year extension to the plant's operating license from the U.S. Nuclear Regulatory Commission. With license extension, Three Mile Island is well positioned to help meet the growing demand for energy well into the future as power needs across central Pennsylvania and the United States are projected to increase. The operation of Three Mile Island produces no greenhouse gas emissions and improves the air quality of the region.

Three Mile Island's original operating license was set to expire in 2014, but with license extension, TMI can continue to provide central Pennsylvania with safe, clean and reliable energy until 2034. Visit the License Renewal section to read about the license renewal process that Three Mile Island recently completed, as well as documents released by the NRC about TMI's safe and environmentally friendly operations.