Page 1 of 2 In press coverage of the alternative energy boom, new energy gets all the press. Solar panels, windmills, tidal generators, biofuels: They fill our minds with visions of plentiful and clean power. We dream of ethanol, and bio-diesel, and plug-in hybrids. But one of the biggest and most untapped opportunities - both for the planet and investors - lies not in creating new energy, but in advancing energy efficiency. No, we're not talking about Jimmy-Carter-in-a-sweater-style energy efficiency; we're talking major technological advances with profit potentials that measure in the billions. The biggest opportunity of all may lie in improving the efficiency of the nation's power grid - the complex of wires, substations and transformers that take power from where it's made (at the power plant) to where it's used (at your home). According to Bob Fesmire, the U.S. spokesperson for the power technology division of the ABB Group, there's a 6% - 8% differential between power generated and power sold in the U.S. That missing juice represents a 250-billion kilowatt-hour resource worth $20 billion per year if you could actually resell it, ripe for harvest and free from the environmental impact you'd get if you actually generated that additional power. So forget, for the moment, the front-loaded glamour of new power-generating technologies from fuel cells to fusion. Turn instead to the freewheeling frontier of power distribution and transmission; territory that for the moment is being productively homesteaded by said ABB Group, a Swiss corporation (formed by the 1996 merger of the Swedish company Asea and the Swiss company Brown Boveri), and also, to some extent, by the German Siemens AG, a company that reaches more broadly across many other industries and technologies. High-Voltage Direct Current One area that's getting a lot of play is high-voltage direct current. Dusting off the old AP physics textbook, we know that the flow of electricity in a circuit is related to two things: voltage, amperage and resistance (Ohms(=)).To use the high-school-level analogy, the voltage is the water pressure - how motivated the electrons are to get moving. Amperage is the size of the pipe - bigger pipes mean more flow, more electrons getting where they need to go. A given number of electrons - a useful amount of power - can be pushed through a system at high voltage and low current (your pressure washer), or low voltage and high current (dumping out the kiddie pool onto the lawn). It's kind of like a teeter-totter. Joule's law tells us that the amount of loss in electrical transmission (through heat) is proportional to the square of the "current." In other words, if we cut the current (amps) in half, we will cut the loss in the system by 25%. So the lower the current, the more efficient the system. That's why the nozzle of the power washer heats up - resistance turns into heat. We use high-voltage (and low-current) transmission lines to transfer power long distances because they do so with lower currents, and therefore, less power loss. Most of the electricity distributed around the world is distributed as alternating current, which means the voltage and current switch back and forth in direction every 1/50th of a second. AC has been the dominate form of electrical distribution for years, but it's not the only way. Direct current - or DC power - is actually a stabler and more efficient way to transmit power over long distances than AC. The ABB Group pioneered the use of high-voltage DC transmission systems in 1954 with a submarine line connecting the island of Gotland to the Swedish mainland, and in the 1960s, during the heroic age of U.S. public works projects, with the 846-mile Pacific DC Intertie that connects Los Angeles to the hydropower resources of the Columbia River on the Washington-Oregon border. The major challenge with DC current is that it has historically cost more to set up than competing AC counterparts. DC current must be turned into AC current before it can be used in factories and homes, as the local electrical grid is AC-only.
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