Betting on wave dragons, sea snakes, green crude, power kites and other cleantech innovations to fuel the planet.
Hydroelectric dams come with their own environmental collateral, crop-based ethanol turned out to be far from sustainable (and in some cases worse than fossil fuels), and the dream of the hydrogen economy remains elusive. But newer and greener technologies are
in development within the renewable energy sector, which is already seeing big growth in wind farms, solar power towers and other forms of clean energy. Here are five of the emerging cleantech trends you won’t want to miss.
1. HIGH ALTITUDE WIND ENERGY
Wind speeds are faster high above the ground, so why not go high to harness it?
Italian company Kite Gen is developing power plants that use kites, gliding up to one kilometre above the earth, to generate electricity. The kites are tethered to heavy machinery at ground level, where the power is generated. Current Kite Gen plant designs could produce 100 megawatts (MW)—enough to power maybe 30 to 40,000 homes—but the company is already working on designs for 1,000 MW (1 gigawatt) plants.
Dutch scientists are working on another design, called the Laddermill, which generates electricity from the pull of an array kites rushing upwards and downwards, and Australian company Solartran is working on something similar using hot air balloons.
And Californian start-up Makani Power is also working on a high altitude design—though they are keeping the specifics of their lofty plans a secret for the time being.
2. TIDAL ENERGY / RIVER TURBINES
Hydroelectric dams, though eco-friendly in terms of air pollution, still come with intense environmental collateral: floods can destroy upstream areas, and downstream rivers can diminish to parched trickles. So why not try to harness the energy of flowing streams without damming them?
Already, the Ontario government is installing Verdant Power’s Free Flow Kinetic Hydropower turbines—which look like little underwater wind turbines—in the St. Lawrence River near Cornwall, and a similar system is already operating in the East River in New York.
Farther from shore, tidal turbines are being installed in the ocean to harness the tides—hence the nickname, “lunar power.” Ten-metre-wide hydroelectric turbines, enough to produce 1.5 MW of electricity all together, will be installed in Nova Scotia’s Bay of Fundy (home to the world’s strongest tides), and built by British company Marine Current Turbines. (The company is also behind the 1.2 MW SeaGen project off the coast of Northern Ireland and the upcoming Skerries tidal farm off the coast of Wales, which will generate 10.5 MW when operational.
Also in the mix are Irish company OpenHydro, which will install its open centre turbines (which look more like jet engines) in the Bay of Fundy, and Canadian company Clean Current, which has installed tidal turbines off the coast of Vancouver Island.
3. WAVE ENERGY
And on top of the ocean, other entrepreneurs are learning to harness the energy of the waves themselves to generate electricity.
Portugal is home to the world’s largest “wave farm,” which generates 2.25 MW of power with the upward and downward bobbing of 140-metre-long “sea snakes,” designed by Scottish companyPelamis. The company is also building commercial wave farms off the coast of Cornwall and Scotland.
And other designs are also in R&D, including the Wave Dragon (currently being tested in Wales and Denmark) and PowerBuoys (tested in Hawaii, New Jersey and Spain).
4. THIN FILM SOLAR PANELS
Solar energy has seen big growth in the past several years, especially in the form of huge solar thermal power plants in the U.S., southern Europe and the Middle East. These use arrays of mirrors to heat up water (or other fluids) to drive turbines, which is a more cost-effective way of generating electricity than from flat photovoltaic solar panels (which have become even more expensive in recent years due to the global increase in the price of silicon).
Indeed, the future of photovoltaic solar energy lies in new, high-tech materials called “thin film” solar panels that use very little—or no— silicon at all, and are usually made of flexible metal-plastic hybrids. Even better, they are light, flexible and can be printed off roll-to-roll manufacturing systems much like newsprint, making them cheap to produce, easy to install, resistant to damage (since they are flexible), and adaptable to almost any kind of surface.
A few thin-film solar products are already available from companies including United Solar Ovonic,Daystar Technologies, Konarka and Nanosolar. Though current thin-film products tend to have pretty low efficiencies (around 6 percent, compared to about 20 percent for a standard wind turbine), but they are expected to improve in leaps and bounds as research proceeds. Abu Dhabi’s Masdar Initiative—which will feature a zero-carbon solar-powered city, as well as the cleantech research capital of the world—has targeted thin-film solar technology for large-scale industrial production, aiming to produce 1 GW of thin-film capacity by 2014.
5. ALGAL FUELS
Few new energy sources are generating as much buzz as algae, which convert sunlight into energy through photosynthesis, just like land-based plants, and so can be used in the same way as other biofuel stocks, such as corn.
But unlike corn, soy or palm oil, using algae to create biofuels doesn’t impact our global food supply and use up large tracts of land or fertilizers. And it generates about 15 times more ethanol per acre to boot. Already, the U.S. company Algenol is building a plant with Mexican company Biofields to generate up to 15 billion gallons of ethanol per year, using algae.
Algae has other potential uses: California company Sapphire Energy says they can make a gasoline-like liquid straight from algae, called “green crude,” which was used in the world’s first biofuel-powered flight earlier this year by Continental Airlines. The city of Venice has announced plans to construct power plants that will generate half the city’s electricity from algae. And biodiesel from algae also shows promise—last month scientists announced they had developed the first economical process for producing biodiesel from algae.
And also last month, U.S. researchers discovered a new chemical pathway inside a specific species of algae that generates hydrogen—suggesting that the hydrogen economy might be more attainable than we had thought.