Faced with a surge in the number of proposed solar power plants, the federal government has placed a moratorium on new solar projects on public land until it studies their environmental impact, which is expected to take about two years. The Bureau of Land Management says an extensive environmental study is needed to determine how large solar plants might affect millions of acres it oversees in six Western states. But the decision to freeze new solar proposals temporarily ... has caused widespread concern in the alternative-energy industry ... just as the demand for viable alternative energy is accelerating. It doesn't make any sense," said Holly Gordon, vice president for ... a solar thermal energy company in Palo Alto, Calif. "The Bureau of Land Management land has some of the best solar resources in the world. This could completely stunt the growth of the industry." Much of the 119 million surface acres of federally administered land in the West is ideal for solar energy. Galvanized by the national demand for clean energy development, solar companies have filed more than 130 proposals with the Bureau of Land Management since 2005. According to the bureau, the applications, which cover more than one million acres, are for projects that have the potential to power more than 20 million homes. Craig Cox, the executive director of the Interwest Energy Alliance, a renewable energy trade group, said he worried that the freeze would "throw a monkey wrench" into the solar energy industry at precisely the wrong time.