BusinessWeek reader L.J. Furman is a candidate in the MBA Managing for Sustainability program at Marlboro College Graduate Center in Brattleboro, Vt. He writes about energy issues on PopularLogistics.com.

In July 2008, Al Gore the U.S. to generate 100% of the electricity we need using clean, renewable, sustainable sources within 10 years. “When you connect the dots,” he said, “it turns out that the real solutions to the climate crisis are the very same measures needed to renew our economy and escape the trap of ever-rising energy prices.” Gore connected the dots to the crises we face and drew a picture of nonsustainability. We could meet the “Gore Challenge” via the deployment of 250 gigawatts of wind generation capacity and 50 gigawatts of solar, and it would cost approximately $911 billion. But is “clean, renewable, and sustainable” energy really necessary?

I’d argue yes­—it’s a business imperative. As I commented on the article “MBA Programs Go Green,” “we must shift the business focus from today, tomorrow, and this quarter to the long term, [and] we must also shift the energy paradigm from fossil fuels to conservation, solar wind, and geothermal.”

The question of necessity is easy to answer. In April 2007 the U.S. Supreme Court ruled in Massachusetts vs. Environmental Protection Agencyand Environmental Defense Fund vs. Duke Energy that the EPA must regulate carbon emissions unless it presents scientific proof that greenhouse gases do not contribute to global climate change, and that the EPA must regulate companies that build new or renovate existing power plants and factories under the “new source review” provision of the Clean Air Act. On Nov. 13, 2008, the Environmental Appeals Board (EAB) of the EPA ruled that the EPA had “no valid reason for refusing to limit” carbon dioxide emissions from new coal-fired power plants. The EPA said it will abide by the 2007 Supreme Court decisions and limit carbon emissions from new and proposed coal plants. We need alternatives to fossil fuels, if for no other reason than to obey the law.

Green Calculations

T. Boone Pickens forecasts the costs of the wind farms he wants to build in Texas at $2 billion per gigawatt. The 500 kilowatt solar array in place at the Atlantic County Utility Authority cost approximately $3.25 million, $6.5 billion per gigawatt. The New York Times estimates the cost of new nuclear capacity at $8 billion per gigawatt, not counting the costs of fuel, waste management, or government oversight.

We generate electricity by burning fossil fuels, controlling nuclear fission, putting solar panels in the path of sunlight, and harnessing winds, waterfalls, ocean currents, and the heat of the earth. Like fossil fuel and nuclear plants, geothermal plants use heat to generate steam, which turns a turbine, transforming heat into electricity. Traditional hydroelectric plants, like those at Niagara Falls and the Grand Coulee Dam, harness the kinetic energy in waterfalls. New designs can harness the kinetic energy in tides, waves, and ocean currents. Wind farms harness the kinetic energy in winds. These transform kinetic energy into electricity. Photovoltaic solar systems harness sunlight via the photoelectric effect to create electricity much the way green plants harness sunlight.

Harness, Don’t Consume

These technologies harness a process rather than consume a resource. When we use a process, such as putting a photovoltaic module in sunlight and allowing the photoelectric effect to generate an electric potential, or we put a turbine in the path of a wind or water current, it is as if we have harnessed a horse or hitched a ride on a train that is running regardless of our presence as a passenger. Solar modules will degrade over time. Wind and other kinetic energy turbines need to be maintained, just as nuclear and fossil fuel plants degrade and must be maintained. But solar modules and kinetic energy turbines are not consumed in the manner of coal, oil, or nuclear fuel rods.

Harnessing sunlight, the kinetic energy of winds and water, and the earth’s heat produce energy without fuels. No fuel transport, no greenhouse gases to sequester; no mercury, no radioactive wastes to store and manage. There are no solar mines, wind mines, or hydro-fuel wells.

Learning from Johnny Appleseed

Apple trees produce apples. You can eat the apples year after year or chop down the tree and burn the wood to stay warm or build furniture. But you won’t get more apples. When we consume a resource as fuel, we use some of the energy, waste some, and release by-products into the biosphere. This is inefficient, expensive, nonrenewable, and nonsustainable.

Gore noted that “enough solar energy falls on the surface of the earth every 40 minutes to meet 100% of the entire world’s energy needs for a full year. And enough wind power blows through the Midwest corridor every year to meet 100% of U.S. electricity demand.” To look at our old energy paradigm via this apple tree analogy, we have been chopping down the apple trees and burning them for fuel. Harnessing sunlight, winds, waterfalls, ocean currents, and geothermal energy is like planting apple trees and using the apples as our energy source. Johnny Appleseed would approve.