Taken from http://www.popularmechanics.com/science/research/1766936.html [Accessed on December 18, 2008] 5 New Ideas To Power Our Future - October 2005 Cover Story from Popular Mechanics With the outlook for oil uncertain, it's time for new ideas. Here are five emerging technologies--from buoys that harness the power of waves to bacteria that extract electricity from wastewater. Together they can keep the world humming. BY KRISTIN ROTH
Illustrations by Flying-Chilli.com
Published in the October 2005 issue.
Imagine driving your car for months without refilling your gas tank, powering your home with the energy of ocean waves, or running a laptop computer on electricity generated by your jacket. For anyone facing a gas pump that reads $2.50 for a gallon of regular, or looking ahead to the prospect of record heating oil costs this winter, such visions of energy utopia might seem far off. But today's worrisome energy situation contains a silver lining. Rising prices, increased awareness and new government policies are driving energy innovation to new levels. Some of these breakthroughs will take years to reach their full potential. Others are virtually ready to roll. Will we ever reach a state of infinite energy? In a strict sense, no. There is certainly a finite amount of oil in the Earth. And even the hydrogen that powers the sun will start to run low in, oh, about 5 billion years. Barring a sudden leap in fusion reactor technology (see Next-Generation Hybrid), there won't be one new source of energy that solves our problems in a blinding flash. Instead, progress in meeting humanity's energy needs will come from a combination of cutting-edge technologies. Solar, wind, wave and other alternative energy sources will play a part. So will improved efficiencies as modern technology learns to do more with less. The five bold ideas outlined here will help ease the pressure on fossil fuels. Each is relatively near implementation, and will pave the way for further breakthroughs in production and efficiency. It won't happen overnight, but the pace of change is accelerating as scientists, industry and consumers focus on the problem--and its solutions. Because, in the end, while the sources of energy might be finite, the human capacity for innovation is not. [pic]
A low-wind-speed converter saves voltage that would otherwise go to waste by matching power from a generator to that accepted by a battery.
WIND ENERGY CONTROLLER
Don't live in the Windy City? You don't have to. A small turbine could still provide half your home's electricity, thanks to a simple twist on a standard device. How It Works: In a small-scale wind turbine, the wind rotates the turbine, which spins the generator, which produces AC voltage. But because the wind speed is variable, the voltage is also variable and may be too low to be stored in batteries or fed into the grid. Andy Knight, associate professor at the Department of Electrical and Computer Engineering at the University of Alberta, leads a team that has come up with a system that enables turbines to harvest voltage in relatively calm conditions. With the Knight team technology, the AC current produced by the generator is converted to DC in the rectifier so it can be stored in what is generally a 12-volt battery. Since a battery cannot recharge on voltage that is lower than its output, the team's unique controller monitors the frequency of the AC from the generator. If the voltage is too low to be rectified and sent through the system for storage, the controller directs a switch in the converter to stop the flow of electricity and pool it until the total voltage is 12 volts. The switch in the converter opens and closes about a thousand times per second. By adjusting the ratio of open to closed time, the device precisely controls the voltage. Time Frame: Manufacturers could incorporate the controller now by tweaking existing designs for small-scale turbines. Payoff: "In a region that's borderline...
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