The Chickahominy power station is a 1.65GW natural gas-fired power plant to be constructed in Charles City County, Virginia, US.

Construction of the combined-cycle power plant is expected to be started in 2019, while operations are expected to be started in 2022. Named to honor the Chickahominy Nation, the power station is estimated to generate electricity sufficient to power two million homes.

Chickahominy Power, a subsidiary of Balico, is developing the combined-cycle power plant. The project is expected to create between 800 and 1,000 construction jobs and 35 operational jobs.

Chickahominy power station location and make-up

The Chickahominy power station will be located near the emerging economies of Northern Virginia and Hampton Roads. The site will be located on a 185-acre parcel approximately 3.4km from Roxbury, Virginia, and 10km from Providence Forge, Virginia.

The project will feature three advanced combustion turbine power trains to generate power. The power trains will be equipped with air-cooled condensers in order to minimise water usage.

The plant will include three 1x1 power blocks comprising M-501 JAC gas turbines, three steam turbines, a heat recovery boiler, and three generators. The body parts and accessories of the gas turbines are proposed to be manufactured at the Takasago Plant owned by MHPS and assembled at the Savannah plant.

The power block will feature a combustion turbine generator (CTG) as well as a heat recovery steam generator (HRSG) providing steam to the steam turbine generator.

The heat recovery steam generator (HRSG) will be equipped with supplemental duct firing capabilities, and selective catalytic reduction technology for nitrogen oxides (NOx). It will also feature an oxidation catalyst for CO/VOC reduction.

The combustion turbine will comprise of a reheat, condensing steam turbine generator, which will receive high-pressure super-heated steam from the HRSG. The steam will be exhausted to the reheat section of the HRSG.

The steam turbine generators associated with MHPS turbines are designed to produce 178MW of electric output.

The project will comprise two 84MMBtu/h auxiliary boilers, a diesel-fired emergency generator and fire water pump, two diesel storage tanks, and circuit breakers. The auxiliary boilers will supply steam to the steam turbine generators at start-up and at cold or warm starts to warm up the HRSG.

It will also include three fuel gas heaters, operating at 12MmBtu/h, to warm up the incoming natural gas fuel to prevent freezing of the gas regulating valves.

Fuel supply system for Chickahominy power station

Natural gas for the combined-cycle power plant is proposed to be sourced from the Marcellus shale formation.

Off-take of electricity

The power generated by the Chickahominy power station will be distributed to the regional grid through the Pennsylvania-New Jersey-Maryland Interconnection (PJM) transmission circuit.

Chickahominy power station infrastructure

A 3MW ultra low sulfur diesel (ULSD)-fired emergency generator will be installed at the palnt to provide power in emergency situations. A 376bhp ULSD-fired generator will be installed to serve as fire water pump driver.

Other infrastructure elements include circuit breakers and two distillate oil storage tanks with a capacity to store 572 gallon and 2,500 gallons, respectively.

The project is in close proximity to two existing electric transmission lines and a substation. A natural gas pipeline from Virginia Natural Gas Company is currently supplying gas to the area.

Contractors involved

Gemma Power Systems was awarded the engineering, procurement, and construction (EPC) contract for the combined-cycle power plant, in June 2018.

Mitsubishi Hitachi Power Systems is the supplier of turbine technology and accessories for the project, while Sargent & Lundy was engaged as the design engineer.