Natural gas fired electric power generation plants experience a reduction in power output when the ambient temperature exceeds 60°F. In order to maintain the power design output of this generating plant in Texas during hot days, TAS Energy provided a “Turbine Inlet Chilling” retrofit in 2009. In 2008, the plant began design of a second 7FA-powered 2×1 turbine for the site, options including Turbine Inlet Chilling (TIC) to maximize the plant’s output were considered. Various solutions were discussed and studies concluded that on a hot summer day, evaporative coolers could only produce 560 MW, whereas TAS Energy’s Generation Storage TM* solution could produce over 600 MW. It was decided that it was economical and beneficial to retrofit one existing unit and incorporate
TIC to the future unit as well.
A 6.1 MG Thermal Energy Storage (TES) tank designed & built by DN Tanks was integrated into the unit’s TIC system. The TES tank supplies chilled water for both combined cycle Units 1 & 2 and allows the plant operator to pull electricity from the grid at night-time hours (and pricing) to chill the water, and stored it for use the following day for cooling the inlet air during the peak demand, thereby reducing the daytime parasitic electric load.
The results of the turbine inlet chilling retrofit include:
- Enhanced power capacity by cooling the inlet air to 50°F, the plant’s output increased from 86% to 104% of the rated capacity
during the critical hot & humid summer months.
- The plant utilizes Generation Storage during warm days to optimize operation, thereby generating additional revenue.
- Use of Generation Storage allows the plant to use stored chilled water at the highest peak power pricing, when the ISO is at its greatest need to service Electronic Reliability Council of Texas (ERCOT’s) load requirements.