39. What is the writer’s attitude towards the sales of fireworks in Beijing?

    A. Negative                    B. Not mentioned

C. Positive                     D. Satisfactory

                  (B)

   People will soon cool their homes with power from the burning desert sun. Deserts are becoming hot spots for solar thermal (热的) power in which futuristic troughs (低谷期) pay more attention to the sun's rays and create steam to run power-producing turbines (涡轮机) at power plants.

   Tiny experimental plants built in the 1980s in California ran into problems when energy prices dropped. But as oil, natural gas and electricity costs soar, companies are racing to build commercial solar thermal plants that are the size of power plants.

   Limits on emissions (释放) of greenhouse gases from fossil fuels have also promoted the new technology. Utah-based International Automated Systems Inc. signed an agreement to build a $150 million, 100-megawatt power plant for Solar Renewable Energy in Nevada. And North Carolina-based Solargenix will break ground on a 64 MW, $100 million solar thermal plant called Nevada Solar One.

   Currently, all the types of solar energy provide only about 1 percent of U. S. power. One problem is price. Solar thermal at present costs about 12 to 15 cents per kilowatt hour, Westerholt said, compared with natural gas power which costs 10 cents per KWH. But as production grows, solar companies expect costs to slip to 8 cents per KHW in five years.

   Solar thermal is expensive compared with wind energy and fuels. But it does have advantages. Power from the desert sun is more reliable than wind power during the day. And unlike fuels, it has no greenhouse gases.

    And solar thermal is growing globally. A white paper says that by 2040 solar power could satisfy more than 5 percent of the world's electricity demand. The best places for it are Australia, the United States, Spain, the Middle East and North Africa, which could export power from the sun to Europe on high-tech power lines.

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