by Justice Litle
Wouldn't it be nice if we could surf our way to energy independence?
Complete freedom from fossil fuels is a pipe dream - for the next few decades, anyway. But maybe we can get to a place of significantly less dependence on them. As demand relentlessly outstrips supply in the coming years, we'll have to cut back no matter what. It will merely be a question of how rough the ride turns out to be.
Going back to the surfing analogy, the basic ingredients of a good wave aren't hard to guess: wind, water and sun. There are interesting developments taking place in all three areas.
We'll start with wind. On June 28, at the 2006 Wind Power Asia exhibition in Beijing, China unveiled a major technological breakthrough: the first ever "Maglev generator," or permanent magnetic levitation wind power generator. The Maglev generator is expected to produce 20% more output than previous wind turbine designs, while cutting operating expenses in half - generating power in the range of five cents per kilowatt hour. The Maglev generator can also make use of significantly lower wind speeds than previous designs, likely due to the same frictionless operating principle that Maglev trains use to travel at more than 300 miles per hour. Lower wind speed requirements mean the new turbine can be deployed effectively in far-flung rural areas, and the vastly improved economics make it a competitive alternative to fossil fuels. As a side benefit, the breakthrough gives China new incentive for respecting intellectual property rights, as it now has some highly valuable IP of its own to export.
Back in the United States, General Electric has partnered with the U.S.
Department of Energy to develop a crop of giant new wind turbines over the next three years. At up to seven megawatts, the new turbines will be almost twice as powerful as existing ones, each one capable of powering a thousand homes. At 95 meters, these monsters are as tall as a football field, and destined to get larger over time. As the turbines grow in size, however, the problem of "visual pollution" becomes more acute. East Coasters don't like having their ocean views ruined by ugly structures too close to shore.
The solution? Tow the suckers out to sea, where the wind is better anyway. The MIT Technology Review reports:
MIT researchers recently demonstrated the feasibility of "tension-leg" platforms, a technology that oil companies have recently adopted for deep-water rigs. The wind turbines and towers would be assembled at a shipyard and placed on top of large floating cylinders. The canisters would be ballasted on the bottom with high-density concrete to keep the structure from tipping over, and the whole turbine assembly would be tugged out to sea.
There, four steel cables would be attached to the platform, anchoring it to the sea floor. First, though, some water would be allowed into the cylinder, causing the structure to sink more into the water. Once the cables are attached, the water is pumped back out again, allowing the turbine to rise, tightening the cables and preventing the turbine from bobbing up and down, yet allowing some lateral movement that would help cushion the impact of storm waves on the tower. (The blades themselves would be high enough to avoid even waves from hurricanes.)
Two of the biggest challenges for this out-to-sea approach will be maintenance and durability. The turbines will have to be incredibly durable to endure the regular battering they will take from wind and waves. Sending out a repairman will be no small task. But Jim Lyons, the leader of Advanced Technology for GE's Wind Energy Division, believes wind could handle 20% of U.S. energy needs - as much as nuclear power handles today.
Other alternative energy companies are less focused on the wind and more interested in the waves. Ocean Power Technologies (OPT), the first ever wave-power company to list on the London Stock Exchange, has focused on perfecting a remarkably straightforward concept. OPT's "PowerBuoy" system utilizes a piston that moves up and down with the waves, as if the sea itself were turning a hand crank. The piston is connected to a generator, which, turned by the movement of piston, generates electricity and stores it in a battery.
The buoy concept carries great advantage in its simplicity. More complex wave-energy devices have typically proven to be not durable enough, or vulnerable to storms; making them "sea-proof" was cost prohibitive. OPT claims its low-impact PowerBuoy setups can last in the open sea for decades, thanks to simplicity of design and special sensors that constantly monitor the ocean environment for changing conditions. In the event of rough waters, the PowerBuoy can suspend operations and disconnect itself, resuming operations when wave conditions return to normal. OPT has wave-power stations off the coasts of Spain, France and Hawaii, and will soon be embarking on its first project for the United Kingdom, a 5MW (five
megawatt) installation off the north coast of Cornwall. For this project, 30 separate PowerBuoys ranging in capacity from 150-250 kilowatts each will be deployed in 2007 and 2008.
Last but not least, alternative energy life is stirring in the sun-baked deserts of Southern California, with the help of an ingenious 19th-century concept. Two major utility companies, Southern California Edison and San Diego Gas and Electric, are working with a Phoenix company, Stirling Energy Systems, to harness the power of the California sunshine. It is said to be the biggest solar effort in the world so far - bigger than all other solar projects in the U.S. combined. After a period of testing and scaling, production is slated to begin on the larger of the two planned sites in 2008. Upon completion, the new Mojave Desert facility should produce a whopping 500 megawatts of electricity per day by 2012, enough juice for 250,000 homes. And it will be done without solar panels.
The nearly 190-year-old technology being employed for the project is the Stirling engine (for which Stirling Energy Systems is named). Invented in 1816 as an alternative to the dangerous steam engines of the day, which had the annoying tendency of exploding every now and then - the Stirling engine contains a sealed gas - in this case, hydrogen. Piston movement is generated by heating the hydrogen and forcing it to expand through hot and cold heat exchangers. For the 500MW site, the sun will be precision-tracked by 20,000 swiveling mirrored dishes spread over 4,500 acres, each of them 38 feet in diameter and reflecting their intensely concentrated rays into a powerful heat source for thousands upon thousands of Stirling engines. The setup is expected to convert 30% of the sun's available energy into electricity, which is an efficiency rate double or triple that of present-day solar panels.
These examples only scratch the surface; there are too many initiatives and innovations under way to mention even a fraction of them all. Common themes are cost of manufacturing, ease of maintenance, durability and efficiency. All these elements are improving as our knowledge increases and technology marches forward. Of course, we will not be spared the harrowing effects of Peak Oil in the meantime. The transition from traditional fossil fuels threatens to be drawn out, messy and painful, as we have already seen.
But there is still some great alternative surf out there, and a better world waiting when we make it through the bottleneck.
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