4.1. SR 10-06-1997 - Laserfiche WebLink

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SUN POWER WARMS UP THOUGH THE BASE is small, solar electricity is getting bigger. U.S. silicon photovoltaic cell pro- ducers, which command more than a third of the world market, rang up a 35.5% in- crease in shipments last year, to a record $148 million. Wholesale factory prices for the solar modules, more than half of which were exported, ranged from $3.90 to $4.35 per watt of capacity, according to the trade newsletter PhotoVoltaic News. While that can't compete with conventional power costing as little as 50 cents per watt of ca- pacity, demand continues to grow where sun power has long made sense: at remote water-pumping stations, roadside tele- phone call boxes, and isolated locations in the Third World. Some power companies are experi- menting with erecting arrays of solar cells to relieve peak-hour demands where up- grading transmission capacity is expen- sive, such as suburban neighborhoods served by buried cables. The hottest part of the day, when people want air condi- tioning, coincides with the hours when so- lar cells put out the most juice. But while the cost of photovoltaic installations keeps falling, these projects can't yet pay their own way. One utility has jumped into a solar business that can stand on its own. Idaho Power in Boise has developed a line of 200- to 800-watt solar systems that it in- stalls, owns, and maintains at remote sites such as ranchers' houses and water pumps supplying cattle troughs. The residential setups consist of a solar power array, DC to AC inverter, storage battery, and small backup generator fueled by propane. Idaho Power owns this photovoltaic unit--with a battery for cloudy days-- which it set up at the home of Wendell and Leola Jones near Boise. Most of the systems re- place small, noisy diesel generator sets that re- quire frequent mainte- nance. So far 30 of the systems, for which Idaho Power charges a flat fee of $20 to $150 a month depending on their size, are in place; 70 more are scheduled for installa- tion by the end of the year. Idaho Power's biggest solar job involved replac- ing most of the diesel 9 power at an Air Force ra- ~ dar site 41 miles from the ~ nearest power lines. In 5 the past, Air Force crews relied entirely on diesel fuel that had to be hauled over difficult roads to reach the facility, which now can be kept open during winter months when snow and ice block access roads. In a new joint venture, the utility aims to export stand-alone renewable en- ergy systems to developing countries. Other promising solar ideas are gestat- ing in corporate labs. Cummins Engine of Columbus, Indiana, has been working since 1988 on seven- and 25-kilowatt sys- tems that use solar heat reflected from circular mirrors to run a version of the Stirling engine, whose pistons move when the gas surrounding them is heated. The engine in turn drives an alternator that makes the electricity. Though Cummins is a leading maker of diesel engines, its goal is to match or undercut the "life cycle" cost of diesel-electric power when solar energy's low maintenance and free "fuel" are figured in. search, and so are a number of foreign auto- makers. Though the hybrid car might be less expensive than a battery car, it would still be too pricey, at least initially, to supplant very many of the world's millions of piston- powered gasoline engines. Ultimately, the market for low-polluting cars will be con- trolled by the EPA's mandates on exhaust emissions and fuel-economy standards, which are subject to the whims of politics. "Without mandates, the automotive market won't go anywhere," says Charles Weinstein, director of advanced technology at AlliedSignal. No political mandates are required to open the microturbine's other big market --electric power for stationary uses. The challenges are all technical. Small turbine generators called auxiliary power units, which have been used in airliners for years, wear out fairly quickly. And because they are produced in small volumes, require complex gearing arrangements, and perform other tasks besides supplying electricity, their price--about $1,000 per kilowatt of capac- ity-is too high for them to qualify for a role in today's earthbound electricity wars. Not to worry. The microturbine engineers at AlliedSignal and Capstone hope to squash costs not only through simplified design but also by borrowing production techniques