Fewer emissions. Less water usage. And more power.

That's the concept GWF Energy is selling to state regulators as the company seeks to convert the existing power plant in Hanford's industrial park to a so-called "combined-cycle" plant. Through the conversion, GWF wants to capture heat that is usually released into the atmosphere -- with it, some greenhouse gases and an ozone precursor -- in the operation of gas turbines and turn it into steam to produce more electricity. The company has a similar plan for its Henrietta plant near the Lemoore Naval Air Station.

Both projects must be approved by the California Energy Commission and the San Joaquin Valley Air Pollution District.

On Tuesday, company officials presented an overview of their plans to Hanford city leaders in an informational session. Although the project would not require city approval, it would affect the city. While the project could mean more property tax revenues and reduced air pollution, it could also mean an increase, however slight, in water use.

GWF says the proposal is part of its greening effort.

"Because of this push toward renewable energy and because those types of energy don't generate all the time and are somewhat unpredictable, it's our view that the backbone of the system will still have a fossil fuel component," said Doug Wheeler, GWF vice president. "So that fossil fuel component needs to be as efficient as we can possibly achieve. That's where this combined-cycle technology comes in."

The $110 million project will install new technology that would remove the waste heat from the first cycle and let it go through a boiler to generate steam that turns a second set of turbines, allowing the facility to generate an extra 25 megawatts, according to the California Energy Commission. The existing Hanford plant has a capacity to generate 95 megawatts, providing energy to about 95,000 homes.

According to GWF, the combined-cycle conversion would cut the greenhouse emission from the Hanford plant by half, from 6 parts per million to 3 ppm, and reduce the nitrogen oxide emission by about 30 percent, from 3.6 ppm to 2.5 ppm.

The plant will use a dry cooling system, minimizing the increased water use at 8 acre feet per year. That's a far more efficient option compared with a conventional cooling water system, which would use 425 acre feet of water each year, GWF says.

City leaders' reaction to GWF plans was favorable.

"I think they're trying to be environmentally efficient about it. What they are trying to do will also reduce the emissions, so it sounds like a win-win deal," said Mayor David Ayers. "They seem to be sensitive to the fact that there isn't much water out there by using the air-cooling method to minimize the water usage. That also makes it a good project. I have no qualms about it."

The conversion would also provide the plant with flexibility, Wheeler said.

The retrofit would allow the plant to run through an energy-efficient combined cycle when electricity needs are predictable. But in an emergency situation requiring a quick supply of megawatts, the plant could still run in a simple cycle, which takes much less time to generate power, Wheeler said.

GWF Hanford is called a "peaker plant" that runs only when there is a high demand for electricity. That usually occurs during summer months when the air conditioning load is high and during the holiday season when consumers put a strain on the power grid by cranking up the heat and plugging in the Christmas lights. In a typical year, the Hanford plant runs about 1,500 hours a year.

The permit application for GWF's latest proposal, filed recently with the energy commission, is expected to be processed within a year.

If everything goes well, construction could start in early 2011, with a goal of starting operation of the combined-cycle plant in 2012, company officials said.

The reporter can be reached at 583-2429.

(Dec. 17, 2008)