Niagara Blower of Buffalo, New York, has been selected to engineer, manufacture and supply a Wet Surface Air Cooler (closed-loop, evaporative ) for the Calpine Otay Mesa power plant located in San Diego County, California.

The Wet Surface Air Cooler will cool the plant’s main loop water and optimise use of scarce water resources.

The project will build on experience with the Wet Surface Air Cooler for auxiliary loop cooling and vacuum steam condensing at a number of simple and combined cycle power plants.

The Wet Surface Air Cooler is a natural evaporative heat rejection device used to achieve the coldest possible process outlet without the need for refrigeration (process outlet below ambient wet bulb).

The WSAC technology combines elements of a tubular heat exchanger and cooling tower in a single structure.

It offers a cost-effective heat transfer technology, providing lower outlet temperatures and requiring less space and using less power than some of the alternatives.

The Wet Surface Air Cooler can also use poor quality water as spray makeup.

The Wet Surface Air Cooler at Calpine Otay Mesa will blowdown (waste) significantly less water than traditional cooling systems, says Niagara Blower. “Less operational horsepower is used to reject the same amount of heat. This translates directly into lower operating costs and better overall plant efficiency.”

After several years of delays, the 596 MWe Otay Mesa generating project will be the first new power plant to be built in San Diego County in nearly 30 years.

The power plant is expected to enter operation in mid-2009.

It has been estimated that getting on for half of fresh water usage in the United States can be attributed to power production.