N.M. planning commercial solar plant
LPEA supplier is one of several partners in project
July 3, 2008
By Dale Rodebaugh | Herald Staff Writer

The company that supplies power for La Plata Electric Association has joined three other large electricity providers in New Mexico to build that state's first commercial solar-powered generating plant, it was announced this week.

Jim Van Someren, spokesman for Tri-State Generation and Transmission Association, said Tuesday that the process started last year when several partners approached the Electric Power Research Institute, a nonprofit research and development firm, to propose a feasibility study regarding concentrated-solar power.

"So our request Monday for proposals to develop the plant is really the second step," he said.

Tri-State's partners in the venture are Xcel Energy, Public Service Co. of New Mexico and El Paso Electric. Southern California Edison and San Diego Gas & Electric were involved early in the process but dropped out. Tri-State is LPEA's supplier.

Although Durango-based LPEA will not be involved in the New Mexico project, LPEA General Manager Greg Munro said that eventually there could be a similar project in La Plata County.

"Ideas are floating around here but nothing as big as Tri-State," Munro said. "The Southern Utes are interested, and we'll be talking to them."

The problem is infrastructure, Munro said. There is no simple way to connect to the grid.

Electric Power Research Institute conducted the feasibility study. It assembled a team of experts from electric utilities and engineering firms to guide assessment of concentrated-solar technology, plant location and economic, environmental and regulatory issues.

Out of the study came a project aimed at building a plant in New Mexico to use parabolic-trough technology to produce 211,000 to 375,000 megawatt-hours of electricity a year. The ability to store electricity would be a plus.

A pair of locations near Albuquerque and a location near Lordsburg, in the southwest corner of the state, have been mentioned as sites for the plant.

Parabolic-trough technology - used at three commercial-sized plants in California and one in Nevada - relies on banks of trough-shaped mirrors that focus solar rays on an oil-filled tube, Van Someren said. The hot oil generates steam to operate a generator.

When energy can be stored - as opposed to power that is used instantly - parabolic-trough technology can generate electricity on cloudy days and at night, Van Someren said.

It's estimated that parabolic-trough plants require five to 10 acres per megawatt. A plant meeting the study specifications could satisfy the electrical needs of 29,000 to 52,000 New Mexico homes.

"It looked viable," Van Someren said. "So we used the information to put out a request for proposals."

By comparison, the proposed Desert Rock project in New Mexico involves two coal-fired 750-megawatt generating units. If the plant ran full bore, 24 hours a day, 365 days a year, the plant would produce in excess of 13 million megawatt-hours of electricity a year. That's 35 to 60 times more power than the New Mexico solar plant is expected to produce.

The partners hope to winnow construction proposals to two or three and then negotiate a contract by the end of the year, Van Someren said. If regulatory requirements are forthcoming, the plant could be operating by the end of 2011.

Who will own the plant hasn't been determined, Van Someren said. That decision is step No. 3.

"If the wheels of justice turn slowly, the wheels of utility resources development are even slower," Van Someren said.

Also to be determined is how power from the plant would be divided among the partners. Tri-State probably would have a minority share since it's small relative to the others, Van Someren said.

Overall, the availability of land, reliable sunshine and the ability to deliver electricity determine where solar-powered generation plants are located, Van Someren said.

A story in last week's Business Week about the development of wind power in Kansas cited the importance of plant location. While Kansas has some of the strongest winds in the country, there is no adequate grid to deliver power to the east and west coasts where the bulk of demand is, according to the story.

Electricity from the New Mexico plant would be used by in-state consumers.

None of the power Tri-State presently generates comes from the sun's rays, Van Someren said. The Tri-State energy mix comes 70 percent from coal, 15 percent from other providers who use a variety of sources, 12 percent from water projects and 3 percent from natural gas, which is used to satisfy peak demand.

Tri-State, based in the Denver suburb of Westminster, supplies power to 44 electric cooperatives in four states - 18 in Colorado, 12 in New Mexico, eight in Wyoming and six in Nebraska.