The company's decision was based on lack of state and federal energy policies in the promotion of zero-emissions energy.

The move is expected to impact 675 employees and also 1,500 contracted workers at the nuclear plant located in Dauphin County, Pennsylvania.

The Chicago-based nuclear power generation company stated that Three Mile Island will be retiring on or about 30 September 2019 in the absence of policy reforms.

It said that without policy reforms, the subsequent loss of nuclear plants in Pennsylvania would result in increased levels of air pollution.

Further, Exelon said that the plants’ closure will reduce the stability of the electric grid, increase energy prices for consumers, and affect thousands of well-paid jobs besides weakening the economy of Pennsylvania.

The energy company expressed disappointment at the exclusion of nuclear power in the state’s Alternative Energy Portfolio Standard (AEPS) although 16 clean power sources were included in it and backed by the state energy policy.

Exelon president and CEO Chris Crane said: “Like New York and Illinois before it, the Commonwealth has an opportunity to take a leadership role by implementing a policy solution to preserve its nuclear energy facilities and the clean, reliable energy and good-paying jobs they provide.

“We are committed to working with all stakeholders to secure Pennsylvania’s energy future, and will do all we can to support the community, the employees and their families during this difficult period.”

Among the immediate actions, Exelon would be taking in connection with TMI’s retirement is to end capital investment projects required for its long-term operation. It would also cancel 2019 fuel purchases and outage planning.

On 28 March 1979, the power plant’s Unit 2 had a partial reactor meltdown owing to technical malfunction and human error. For several days after the incident, radiation was released forcing thousands of residents to be evacuated for safety.

Image: The Three Mile Island nuclear power plant pictured in 1979. Photo: courtesy of United States Department of Energy/