Renewable energy sounds great, but there are a bunch of problems. For example, half the time you can’t even use it.
It’s hard to get wind power when the wind isn’t blowing, for example. Likewise, it’s hard to get solar power when it’s cloudy.
So researchers are dumping billions of dollars into trying to find alterative energy technologies that provide power as consistently as, say, oil. Or nukes.
And here’s the good news: They say they’re this close to cracking the code that will lead to unlimited energy for all.
The Harvard Business Review has identified six sources of permanent alternative energy at various stages of development. There is no guarantee they will work, of course. But at least they’re trying.
Conventional wind turbines stop when winds die down. But at altitudes of 1000 to 1500 feet where winds are ever strong, there is enough energy to power civilisation 100 times over.
Magenn Power, based in Ottawa, Canada, is building turbine-bearing balloons or rotors that intercept energy at those heights. They hope to make the world's first commercial high-altitude turbine called MARS--a 60-foot-diameter helium-filled blimp--by 2010.
Scientists hope that algae could be genetically engineered to continuously secrete oil that can be refined into fuel. The technology already exists but is not quite economical.
Many companies are investing heavily, including the U.S. government, which has earmarked $50 million for research. Key players, Synthetic Genomics (led by J. Craig Venter) and Sapphire Energy (led by Bill Gates), are engineering algae to produce algae gasoline. Exxon is also spending hundreds of millions on algae.
The ocean is an immense and mostly unharnessed source of power. As the wind blows over the surface of water, it generates waves that contain concentrated energy. Generators that catch the waves can power up to 2,000 terawatts per hour each year. This is equivalent to the market for nuclear and hydroelectric power.
The world's first commercial wave-farm was commissioned off the coast of Portugal by Scotland's Pelamis Wave Power. Each generator is 13-feet in diameter, and supplies enough energy to power 500 homes.
Conventional geothermal systems trap the heat of the earth near the surface. But enhanced systems currently under development can inject cool water two miles inside the earth for super heating. And it can work anywhere.
Australian company Geodynamics expects to start up a one-megawatt power plant, among the world's biggest, as early as 2010. Projects are also underway in France, Switzerland, Germany, California and Japan.
Solar cells are not much use when it's cloudy, dusty, or night-time. Using cells positioned in space can harness the power of eternal sunshine and beam it onto earth in the form of radio waves.
The U.S. Department of Energy and NASA have spent $80 million over 30 years in research. In 2007, the DOE and the tiny nation of Palau started testing the concept with a satellite 300 miles above the earth.
The start-up Solaren has signed a contract with California's Pacific Gas and Electric to deliver electricity from space in 2016.
Photo courtesy NASA
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