Energizing Wood Power: Replacing Fossil Fuels

by Heather Kaplan

Three towering smokestacks rise from the fossil fuel-fired Schiller Power Station in the quaint New England city of Portsmouth, New Hampshire. Built more than 50 years ago, Schiller is a striking example of a dirty, coal-burning power plant, exempted from Clean Air Act standards and known as one of the “dirty dozen” power plants in New England. Ray Faulkner, who lives a few miles downwind from Schiller, recalls several occasions when his children’s toys were blanketed with a film of black coal dust.

But something revolutionary is in the works: Schiller expects by December 2005 to become the first coal-fired power plant in the nation to fully convert one of its boilers to burn a renewable source of fuel known as “woody biomass” – typically wood chips, wood waste and small trees.

Burning woody biomass has not always been considered a clean technology, since it often aggravates air pollution and exacerbates respiratory disease. But a combination of new processes with wood’s natural advantages over coal can turn wood into a low-emissions energy resource. Burning woody biomass instead of coal reduces emissions of sulfur dioxide (the primary cause of acid rain) by more than 95% and nitrous oxide (the primary component of smog) by more than 70%.

Public Service of New Hampshire, the company that owns and operates Schiller, plans to replace one of its three fossil-fuel boilers with a high efficiency, wood-fired boiler. The plant will get its fuel from locally generated wood chips, sawmill residue and other clean low-grade wood materials and wood byproducts such as tree tops and branches normally left behind in the wood-harvesting process.

“It is a very exciting project,” says Gary Long, president of Public Service. “It will create an important new market for New Hampshire’s wood industry and the workers and suppliers who depend on that industry for their livelihoods.”

While generating enough electricity to power approximately 50,000 homes, the boiler’s conversion may spur the reduction of more than 380,000 tons of emissions annually.

Some environmentalists are cautiously optimistic. Nathanael Greene, senior policy analyst for the Natural Resources Defense Council, says the company must guarantee that the wood waste is free from toxic contaminants and that the low-grade wood materials are harvested in an environmentally responsible manner. Since errors such as mixing lead paint-covered shingles or arsenic-treated planks into a load of wood chips can create a hazard worse than coal dust, Greene calls the decision to burn waste wood “a complicated issue.”

Public Service’s decision to switch to a renewable energy source is influenced by innovative policy decisions made by neighboring states to the south. Massachusetts and Connecticut have both recently passed Renewable Portfolio Standards that require utilities there to buy a certain percentage of their electricity from renewable power sources. These regulations are establishing a market for Renewable Energy Credits, which can be sold to companies that are required to either produce renewable energy themselves or buy paper credits representing the environmental benefits of an energy project.

Although just buying a credit may sound much less environmentally friendly than building a wind turbine, for example, in fact the benefits are almost identical: Revenues generated from the credits create the financial incentive for another utility to build a wind turbine or, in the case of Schiller, to convert a filthy coal boiler into a cleaner biomass boiler.

New England-based energy policies aren’t the only political force driving new wood power projects in the U.S. The federal departments of Energy and Agriculture recently awarded $23 million to fund 19 biomass projects with appropriations from the 2002 Farm Bill. Last July, the Department of the Interior joined with Energy and Agriculture to sign a memorandum of understanding on “Woody Biomass Utilization” that establishes consistent policies and procedures to support burning wood for power. In the West, some states that feel vulnerable to forest fires are actually offering to pay power companies to harvest more wood for fuel.

Far-cleaner technologies – including gasification – are emerging that can convert either coal or wood into gaseous, liquid or solid fuels before burning. These technologies (which have been touted by the Bush administration as a clean way to produce hydrogen) represent the future of biopower, says Greene. “Over the next 10 to 15 years,” he says, “the industry will be dominated by much cleaner gasification technologies.”

Perhaps the greatest environmental benefit of wood power is its potential role as a “carbon neutral” energy source. Unlike coal, which is extracted from underneath the Earth’s surface and thus releases additional levels of CO2 into the atmosphere when burned, biomass is part of the Earth’s contemporary carbon cycle. When trees are harvested sustainably, their growth absorbs CO2 as fast as their burning can release it. This makes wood power attractive to energy companies such as Public Service that must begin to comply with initiatives in regions like New England that seek to combat global warming.

FROM E Magazine, a SustainableBusiness.com Content Partner.