Natural gas-fired combined-cycle plant
Developer and Owner
Killingly Energy Center is a 650MW natural gas-fired combined-cycle plant being developed in Killingly, Connecticut, US, by NTE Energy (NTE).
The project will involve a private capital investment of $700m. NTE will also own and operate the plant upon completion.
The plant will have a capacity to power 500,000 homes and address the demand for expanding the energy base in the state of Connecticut and the region. It will be a cost-effective energy generation facility with measures for reduced environmental impact.
Connecticut Siting Council approved the NTE’s Certificate of Environmental Compatibility and Public Need in June 2019. Not Another Power Plant, the Connecticut Fund for the Environment, and Sierra Club approached the council to reconsider the approval and later challenged the decision in a court of law.
In February 2020, the Connecticut State Superior Court quashed the appeal, challenging the council’s approval, paving the way for the project to go ahead.
The construction activities for the project are scheduled to begin in the second quarter of 2020 and the plant is expected to begin operations in 2022.
The power plant project will generate 450 jobs during the construction period and up to 25 jobs during its operations.
Killingly Energy Center location
The power generation facility will be located on a 28.3ha area at 180/189 Lake Road in Killingly Town, Windham County, North-eastern Connecticut.
The plant will be located in an industrial area in the northern part of Killingly. The site is bounded by Interstate 395 and Alexander Lake, the Quinebaug River, Lake Road and the Hartford Providence Turnpike.
The area of the site is separated from the residential areas by the Killingly Industrial Park and I-395. The Killingly town is connected to natural gas and electric transmission network.
Killingly Energy Center details
The Killingly Energy Center will incorporate a single combustion turbine generator (CTG) in a 1x1x1 configuration with a steam turbine and a heat recovery steam generator.
The plant will use natural gas as the primary fuel with ultra-low sulphur diesel (ULSD) as a back-up fuel. It will receive natural gas via the Algonquin natural gas pipeline, which will be delivered through an upgraded Yankee Gas lateral.
The facility will utilise Mitsubishi M501JAC gas turbine with DLN combustors, duct burners and heat recovery steam generator. The turbine will improve KEC’s emissions profile and decrease ambient air impact concentrations compared to the previously proposed Siemens SGT6-8000H CTG.
The Killingly energy centre will be connected to the existing Eversource 345kV electric transmission line located adjacent to the site.
Water will be supplied from the Connecticut Water Company (CWC) under an existing contract and wastewater will be discharged via interconnections to the existing Killingly wastewater treatment plant.
Mitsubishi M501JAC gas turbine details
The Mitsubishi M501JAC is an advanced high-capacity gas turbine for 60Hz power generation. It will deliver a combined-cycle efficiency of more than 64% and a rated speed of 3,600rpm.
The Killingly plant will use the Mitsubishi turbine and a TC2F steam turbine in a multi-shaft configuration. It will reduce the amount of fuel consumed by the duct burners.
The M501JAC turbine uses air cooling for combustors instead of steam cooling and operates at a turbine inlet temperature of 1,600°C. It ensures high operability and short start-up time.
The turbine’s combustor has an improved fuel nozzle, which helps to produce a homogeneous mixture of fuel and air.
Its compressor incorporates advanced three-dimensional design techniques for better performance with reduced shock loss in the initial stages and frictional loss in the intermediate and final stages.
Killingly power plant’s sustainability features
Killingly facility’s Environmental Justice Plan was developed in accordance with the Connecticut Department of Energy and Environmental Protection (DEEP)’s Environmental Justice Policy.
The plant is expected to support Connecticut’s commitment to the Global Warming Solutions Act of 2008. NTE aims to reduce greenhouse gas emission levels at the plant by a minimum of 80% by 2050.
It will help displace less efficient and older coal and oil-fired facilities with cleaner power generation units. The facility is expected to be among the cleanest and most efficient natural gas power generation plants in the North America region.
The company made a pledge to either retire the plant in 2050 or operate it with zero net greenhouse gas emissions. It will also consume less water compared to traditional wet-cooled facilities.
Gemma Power Systems, a wholly owned subsidiary of Argan, signed an engineering, procurement and construction (EPC) services contract with NTE Connecticut to build the power plant in March 2020.
Mitsubishi Hitachi Power Systems Americas (MHPS) was contracted to provide the power train, while Tetra Tech prepared an environmental overview report for the project.