Solarplant 1 was a high-tech ghost town near Lake Henshaw in the California desert, halfway between San Diego and Palm Springs. From the highway, it was an indistinct mirage sparkling on the horizon, isolated by rugged terrain and fences warning trespassers to stay away. But from a small plane hired to circle low overhead, the first commercially financed solar-thermal power plant looked like an abandoned movie location from a Western set on Mars.

Lightweight plastic reflectors — an innovation that investors once thought would help make commercial solar power economically competitive — were scattered across the 40-acre property. Thousands of the shiny disks had been mounted on 700 collectors, each shaped like a 30-foot-high satellite dish, which computers once turned to track the sun. But the whole derelict operation had already been idle for several years when I visited it. That was 17 years ago.

Solarplant 1 tells a tale about the end of a technological Gold Rush, one that may haunt those who are responsible for energy policy today. By the time LaJet Energy, a Texas oil company, built the $19 million plant in the early 1980s, energy prices were decreasing from the crisis levels of the previous decade, and Congress and the Reagan administration were reducing federal support for renewable energy. That left it to the entrepreneurs to find their own way to free-market profitability in a challenging new business.

So did LaJet’s experiment in California’s back country, like many alternative energy projects of the same era, fail because changing market conditions and tricky new technology made it uneconomical — or because policy makers and energy utilities were impatient or short-sighted? As with any desert mirage, passersby could probably peer at this one and see what they wanted.

But the question is still relevant. With concerns about rising energy costs, growing dependence on foreign oil and increasing alarm over global warming, government and industry leaders are again exploring ways to develop new energy technologies.

There is no shortage of ideas. A Senate subcommittee, for example, recently heard how nanotechnology-enabled lithium ion batteries could quickly double the mileage of today’s hybrid cars, especially with federal research support and tax incentives to generate consumer interest. Energy executives are also pressing Congress to underwrite large-scale projects to test plans for capturing and storing carbon emitted from coal power plants. Legal and regulatory changes are needed too, the executives say, to make clear who ultimately would be responsible for carbon storage facilities — an issue with echoes of the long debate over nuclear waste.

Others in the energy business say government help would accelerate efforts to increase the efficiency of modern wind turbines, and that extending tax incentives will increase private investment in new solar technology. Incentives have been proposed for making more biofuels too, and to help pay for new gas pumps that would be needed to sell some agriculture-based energy sources. And there is the longer-term promise of hydrogen fuel cells, a favorite of the Bush administration.

Any of these technologies could pan out, but many will not. A venture capitalist would probably spread the risk, investing in a variety of promising inventions in the hope that one pays off big and offsets other losses. That’s difficult in the public sector, where the political cost of any failure can be prohibitively high.

Energy debates of the past have led government officials down many such blind alleys. In the late 1960s, as Washington grappled with the link between air pollution and the internal combustion engine, some prominent scientists and engineers lobbied for federal funding to investigate an alternative transportation energy. The technology was an external combustion contraption known as a Rankine-cycle reciprocating engine — a steam-powered automobile, reminiscent of the famed Stanley Steamers of the early 20th century.

A few entrepreneurs, such as private jet builder William Lear, invested in developing such vehicles; even the big U.S. automakers bankrolled some research. One federal contribution was to help pay for a demonstration project in California that involved testing steam-powered buses in three cities. The results were promising: The buses’ performance “equaled or exceeded the road performance of standard diesel vehicles,” the state reported to the Transportation Department. But more research was needed, and little got done. Needless to say, steam power did not revolutionize late-20th century commuting, despite lingering enthusiasm among a handful of believers.

This is the inevitable fate of at least some of the energy and global warming solutions touted in Washington today. A clean energy revolution may well require direct government investments in research or indirect help in the form of tax breaks or other incentives. If so, the price of success will include some failures — and the stamina to endure them.

Mark Stencel is deputy publisher and a technology columnist for Governing magazine, published by Congressional Quarterly Inc.