2000. Cities within 50 miles include Harrisburg (12 miles to city center), York (13 miles to city center), and Lancaster (24 miles to city center). Electricity Production During its last full year of operation in 2018, Three Mile Island generated 7,355 GWh of electricity. In that same year, electricity from nuclear power produced approximately 39% of the total electricity generated in Pennsylvania (83.5 TWh nuclear of 215 TWh total), with Three Mile Island Generating Station contributing approximately 4% to the statewide total generation. In 2021 the state of Pennsylvania generated approximately 241 TWh total electricity. Three Mile Island Unit 1 The Three Mile Island Unit 1 is a pressurized water reactor designed by Babcock & Wilcox with a net generating capacity of 819 MWe. The initial construction cost for TMI-1 was , equal to $ billion in 2018 dollars. Unit 1 first came online on April 19, 1974, and began commercial operations on September 2, 1974. TMI-1 is licensed to operate for 40 years from its first run, and in 2009, was extended 20 years, which means it could have operated until April 19, 2034. TMI-1 had a closed-cycle cooling system for its main condenser using two natural draft cooling towers. Makeup water was drawn from the river to replace the water lost via evaporation in the towers. Once-through cooling with river water is used for the service water system which cools auxiliary components and removed decay heat when the reactor was shut down. On February 17, 1979, TMI-1 went offline for refueling. It was brought back online on October 9, 1985, after public opposition, several federal court injunctions, and some technical and regulatory complications - more than six years after it initially went offline. Unit 1 was scheduled to be shut down by September 2019 after Exelon announced they did not receive any commitments for subsidies from the state, rendering Exelon unable to continue operating the reactor. TMI-1 was shut down on September 20, 2019. Incidents In February 1993, a man drove his car past a checkpoint at the TMI nuclear plant, then broke through an entry gate. He eventually crashed the car through a secure door and entered the Unit 1 turbine building. The intruder, who had a history of mental illness, hid in the turbine building and was apprehended after four hours. During and following the September 11 attacks, there was a moral panic that United Airlines