The alternatives to alternative energy

As it bobs in the waves, a 70-foot shaft hidden underneath moves up and down, generating power. Because water is denser than air, the friction produces more energy. Finavera's buoys can occupy half the space of a wind farm while producing just as much power, says CEO Jason Bak. The company hopes to commercialize the technology by 2010. "We are on target to generate a whole new industry," Bak says.

Other concepts have drawn government grants. Prometheus Energy, which has designed a process for extracting liquid natural gas from landfill waste, received a $600,000 grant last year from the Energy Dept. to build a refueling station in Sacramento. The company is building a plant at a local landfill that would produce 9,000 gallons of natural gas a day.

And, of course, there are plenty of ideas that have yet to win any backing. One company named KiteShip is proposing to use massive kites to reduce the amount of fuel used by freighters and other big commercial ships. There is some proof behind this concept, at least with smaller boats: KiteShip has long made kites to help power yachts. The company once created a 4,500-square-foot kite to speed a racing yacht in Australia.

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Now executives say they're in talks with four shipping companies to build a $2 million, 13,000-square-foot kite to help haul ships as large as 400 feet long. KiteShip estimates the wind power from that kite would allow a typical commercial ship to cut fuel costs by 10 percent to 20 percent without sacrificing speed. For an average ship, that would translate into $400,000 in savings per year, figures Dave Culp, president of KiteShip and a longtime professional yacht designer. "The economic viability wasn't there until recently," he says. "Fuel was very cheap."

Steve LeRoy, an inventor based in DeKalb, Ill., has also taken a cue from a common force of nature. LeRoy has developed a device that generates lightning to harvest energy from the electrical discharge. The prototype, derived from the coiled transformer developed by physicist Nikola Tesla more than a century ago, can create lightning bolts three feet in length and as loud as a gun shot. Each little bolt only generates enough electricity to illuminate a 60-watt lightbulb for 20 minutes. But a full-scale system, LeRoy believes, could power 30,000 homes for a day with just one lightning bolt. That's not that surprising, considering that an average Midwest thunderstorm releases enough electrical energy to power the entire U.S. for 20 minutes. "If you've ever seen a tree hit by lightning, [you know] it's energy for the taking," LeRoy says.

Likewise, though algae and giant kites may sound like far-fetched solutions to a national energy crisis, it wasn't so long ago that corn was mostly for dinner.

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