Coal plant gives way to combined cycle in New Jersey

Sewaren 7 is a combined-cycle power plant being developed in Woodbridge, New Jersey, US.

Estimated to cost $600m, the new plant is part of PSEG's plan to replace units 1, 2, 3 and 4 of its existing Sewaren coal-fired power plant located on the same site. The units are being retired after approximately 70 years of operation.

PSEG is investing in the new plant in order to take advantage of lower gas prices, as well as to reduce power plant emissions. Construction of the Sewaren 7 plant commenced in June 2016 and is scheduled to be completed by 2018.

The new plant will be equipped with GE's 7HA.02 gas turbines and steam turbines. The plant will include a heat recovery steam generator (HRSG), a fuel gas heating station, an air-cooled condenser, an emergency diesel generator, an auxiliary electrical building, a main stack, and an auxiliary boiler stack.

The air-cooled condenser will be 125ft-tall and include 20 discrete heat transfer cells covering 40,500ft². It will continuously recycle water for cooling purposes, thereby reducing the need for cooling water. The condenser will also decrease the plant's dependence on the Arthur Kill tidal strait for cooling water.

Additional facilities include fuel oil forwarding pump house, fuel oil tank, emissions monitoring building, hydrogen and ammonia storage tanks, and fire water storage tanks. The plant will also be equipped with a 230kV step-up transformer, an auxiliary cooling tower, a warehouse, and a service water pump house.

The plant is designed to operate on two types of fuel, including natural gas and ultra-low sulphur distillate (ULSD) fuel oil.