Tri-State examining solar supplementation
The largest co-op electricity provider, Tri-State Generation and Transmission Association, is examining the possibility of adding solar energy to their fossil-fueled power plants. Tri-State, which is based in Denver, supplies wholesale power to 44 electric cooperatives in four states.
The project, in association with the Electric Power Research Institute, will add steam generated by a solar thermal field to a conventional fossil fuel-powered steam cycle to offset some of the fuel required to generate electric power. Trials are being conducted at Tri-State’s Escalante Generating Station in Prewitt, New Mexico. At plants like the one in Prewitt, coal is burned to produce steam that turns a generator’s turbines to generate electric power, up to 245 megawatts and hour.
“Solar infusion would be used to augment that cycle, such that you could create the same amount of steam with less coal burning,” said Barry Ingold, Tri-State’s senior manager of production assets.
Tri-State says the infusion of solar energy would not only reduce a plant’s carbon dioxide footprint, but also give it the ability to add utility-scale power generation without the challenges of siting a new plant.
“These hybrid power plants will combine the low-cost reliability of existing fossil power plants with the environmental benefit of renewables, and help companies meet federal and state mandates to reduce their emissions of air pollutants and greenhouse gases with renewable energy,” said Bryan Hannegan, vice president of generation and environment at EPRI.
Currently, 27 states in the U.S. have enacted renewable portfolio standard policies. Some included specific mandates that a percentage of the requirement be met with solar energy. The EPRI believes that this technology could be the cheapest way of achieving this because it uses existing plant assets.
Says Ken Anderson, executive vice president and general manager at Tri-State: “We’re pleased to have the opportunity to partner with EPRI on this project and we are eager to learn most about the potential of this breakthrough technology that could further advance the efficiencies at one of our existing generating facilities.”