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Earth, Wind and Fire

By Ed Lawrence | Nov 15, 2008
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That the United States is still relying on nonrenewable energy sources to turn on light bulbs in the 21st century is just nutty. Consider this: there’s more potential wind power in North Dakota, which has few wind farms, than in Germany, for which wind power has been a major power source for years. In fact, scientists contend that the available wind power in the United States could double the amount of electricity currently produced.

On another front, the Solar Energy Industries Association (SEIA) recently released a report stating that 2007 was a record year for solar energy. By SEIA’s count, 314 megawatts of new solar were installed in the United States, an increase of 125 percent from 2006. SEIA president Rhone Resch said solar power is good for the economy.

“Over the past few years, the solar energy industry, which includes manufacturers and distributors of photovoltaic, concentrating solar power and solar heating technology, has pumped over $2 billion into the U.S. economy and created 6,000 new jobs,” he said.

Meanwhile, on Oregon’s Pacific coast, in the middle of the East River in Manhattan, and on a bay in Maine, waves and currents are powering commercial buildings. Not surprisingly, wave and current power are a major source of power in Europe.

So, why are we still relying on other, nonrenewable sources of energy? It appears the obstacles to maximizing these available resources are related to a Catch-22 involving congressional gridlock and fundamental economics.

“The uncertainty relative to the development of wind, solar and wave technologies revolve around the uncertainty of the Congress and the extension of tax credits,” said Reese Tisdale, a senior analyst specializing in renewable and clean power generation at Emerging Energy Research in Cambridge, Mass.

As history has proven, any alternative challenging the status quo faces an uphill battle against entrenched industries and an operating infrastructure.

“From a pricing standpoint, with gas-power electricity being sold, in general, at a price of $0.07–0.08 per kilowatt hour, wind is marginally competitive,” Tisdale said. “At this point, solar costs approximately $0.21 per kilowatt hour.”

But—and it’s a big but—the caveat “in general” is an important distinction. During peak consumption hours, the cost of electricity increases six- to tenfold, while the price of renewables remains constant. Given a broader perspective, the cost of alternative energy may be more competitive than appears at first blush.

The good news for electrical contractors looking for new opportunities is that advances in new technology are on the horizon, and most of them are good for business.

Water power

Among the more intriguing and least complicated of emerging technologies are energy farms located in rivers and oceans. New York University has estimated as much as 12,500 megawatts (MW) of “free flow” (damless) hydropower potential for the United States. The U.S. Department of Energy estimates the potential at 21,000–170,000 MW for North America, including tidal power, wave power, ocean thermal energy conversion, ocean currents, ocean winds and salinity gradients.

On Dec. 12, 2006, Verdant Power of New York installed a free flow turbine at the RITE Project in the East River. The company claims the project is the world’s first grid-connected kinetic hydropower turbine. At present, the turbines are delivering 40,000 kilowatt-hours to a large supermarket and parking garage in Manhattan.

In appearance, the turbines are similar to a wind generator but are anchored in 30-foot-deep water. Their 16-foot diameter rotors are more than 8 feet below the surface, so they do not impede navigation.

“They reach maximum efficiency in only four knots of current,” said Trey Taylor, Verdant president.

Since that current is constant along the river, the turbines are producing energy around the clock. Taylor anticipates that Verdant may add 30 turbines to the farm, increasing production to 1.5 megawatts.

Further north, in Eastport, Maine, the Ocean Renewable Power Co. (ORPC) of Fall River, Mass., has installed an OCGEN generator that is producing energy from continuous flows of ocean current. The OCGEN, which is anchored on the bottom of a bay, generates power when currents push a horizontally oriented blade that rotates around a turbine, producing 250 kilowatts of energy in six knots of current. OCGEN units may be stacked four high. In that configuration, operating at only 30 percent efficiency, the units will produce sufficient energy to power 225 typical homes.

Imagine this: Given these new devices, turbines located at 100 yard intervals along the Mississippi River, between Minneapolis and New Orleans, could power the entire region.

Meanwhile, Professor Annette von Jouanne of Oregon State University in Corvallis and her associates continue testing a buoy that will deliver power to land using wave motion.

“Wave heights measured offshore average 3.5 meters during the winter, which translates to about 50 kilowatts [kW] per meter of crest length,” von Jouanne said. “During the summer, average wave heights are lower, about 1.5 meters, which convert to 10 Kilowats (kW) per meter of crest length. Considering an overall average of 30 kW per meter, the total energy potential intercepted along the entire Oregon coast is in the range of 13,800 MW” That’s double the state’s current 5,000–6,000 MW consumption.

The buoy, tested at Oregon State, creates energy from the relative movement between a fixed spar and the movement of the buoy. Energy will be transmitted to shore through an outflow pipe once used by a now-defunct timber mill.

In an interesting arrangement, prototypes are tested at the university’s O.H. Hinsdale Wave Research Laboratory, which is equipped with the largest wave flume of its type in North America. The flume was constructed using funds donated by Columbia Power Technologies (CPT) of Charlottesville, Va., a privately owned company that entered the wave energy arena in 2002.

“Columbia’s Permanent Magnet Generators present a compelling method to convert the reciprocating motion of wave energy into electrical power using simple, reliable, nonpolluting technology,” said Brad Lamb, CPT president.

Once final development of the buoys is completed, CPT will construct and market them. It may not be long now; the buoy was recently tested for one day one mile from land.

“The buoy has a current capacity of 1 kW that may be increased to 250 kW based on results of testing and refinements in the laboratory,” said Ted Brekken, OSU professor. “The only limiting factor is the wave length.”

He predicted that a “buoy farm” populated by 50–100 buoys could save the amount of energy required to run one large coal-powered generator per year.

Taylor said water power has a lot of potential.

“It’s not a stretch to imagine that 10–15 percent of the electricity needs of this country could be produced by water surrounding it,” he said.

Solar

Solar energy is available throughout the country. However, there have been two limiting factors to solar’s acceptance: the transmission of energy and the manufacture of efficient, cost-effective solar panels.

However, Georgia Institute of Technology professor Ajeet Rohatgi recently invented a panel that appears to overcome that obstacle. Rohatgi, director of the University Center of Excellence for Photovoltaic Research and Education, started Georgia Tech’s photovoltaic program in 1985.

In September 2005, he won a patent for new manufacturing technology. The core of his invention is the creation of an ultra-high-efficiency cell using cheaper manufacturing technology and less silicon than present methods. Rohatgi’s cells are constructed of purified silicon converted to an ingot, which is then sliced into wafers thinner than those currently on the market.

“Solar cell efficiency in the industry is currently at 16 percent, but we have demonstrated 19 percent efficiency in production cells,” he said. “Creating an extra 1 percent of efficiency actually creates 10 percent extra power. That translates to millions of extra dollars in revenue without having to put any additional money into it.”

In an arrangement similar to the OSU–CPT relationship, cells will be produced and marketed by Suniva, a privately owned firm. Suniva is an offshoot of Georgia Tech’s Advanced Technology Development Center, a science and technology incubator that has assisted entrepreneurs in the launch and development of 110 Georgia companies.

“The cell is really key for reducing the overall cost of solar and getting it towards the grid parity you hear everybody talking about,” said Joe Baumstark, CEO of Suniva.

Baumstark anticipates cells rolling off Suniva’s production line by the end of 2008.

Wind

The wind energy industry is moving quickly toward maturity. A recent report by the American Wind Energy Association said the U.S. wind power fleet spans 34 states, and will generate an estimated 48 billion kilowatt-hours of wind energy in 2008, a 45 percent increase over 2007. The growth will add $9 billion to the economy. In addition, 14 new manufacturing facilities were constructed or planned for construction.

Though the potential of wind-generated power is generally accepted, current production represents only 1 percent of U.S. electricity supply, powering the equivalent of 1.5 million homes.

A ringing alarm

Our increasing energy needs, environmental concerns and emerging technology seem to make development and implementation of new technologies a given.

Congress’s recent extension of renewable energy incentives that were scheduled to expire in 2008 caused a sigh of relief. A recent study by Navigant Consulting stated that 16,000 jobs and $19 billion in U.S. investment could have been lost if those credits were not renewed. The study stated that 76,000 jobs were at risk in the wind industry and approximately 40,000 jobs in the solar industry.

LAWRENCE is a freelance writer and photographer based in Bozeman, Mont. He can be reached at [email protected].

About The Author

Ed Lawrence is a freelance writer and photographer based in Bozeman, Mont. He can be reached at [email protected].

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