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Mark Peters

Fuel cells, windmills and solar panels are usually considered the way of the future for meeting the ever-growing demand for electricity.

Burning wood, on the other hand, seems downright old-fashioned.

But that ancient source of energy is getting renewed attention in Connecticut and other New England states as they try to look for renewable sources of power to replace fossil fuels - coal, oil and natural gas.

Three companies have proposed building new power plants in Connecticut that would run on branches, stumps and other woody leftovers. Although they will not replace the huge generating plants people are accustomed to, the state's first wood-fired plants - currently proposed for Plainfield, Watertown and Bozrah - could provide enough power for an estimated 85,000 average homes.

"We don't have a lot of wind," said William Carter of Tamarack Energy, which is developing a wood-fired power plant in Watertown. "The rivers that could be sources of hydro already are, but we have a lot of trees, and we continue to grow a lot of trees."

High and volatile prices for fossil fuels are making wood-fired power plant projects, once seen as too expensive, more feasible. Also, the promise of government subsidies, coupled with long-term contracts with electricity buyers, is making the projects more attractive to investors.

A key step comes Monday, when the Connecticut Clean Energy Fund decides on finalists for multiyear electricity contracts at above-market rates. The contracts would be for producing electricity to supplement the traditional sources of power that are distributed by the state's two utility companies, Connecticut Light & Power Co. and United Illuminating.

Other New England states are seeing similar interest in wood-derived power. Two wood-fired plants are proposed for Russell and Springfield in western Massachusetts, and a subsidiary of Berlin-based Northeast Utilities recently converted part of a coal plant in Portsmouth, N.H., to run on wood, making it one of the larger facilities of its kind.

Unlike other renewable energy sources, wood as an energy source has a long tradition in New England and a proven technology, developers say.

The proposed projects, often referred to as biomass plants, would use technology that is vastly different from any vision of fireplaces or woodstoves. The fuel will not come from clear-cutting forests, plant developers say, but from waste wood that would otherwise end up in landfills or from trees taken down as part of forestry management programs.

Environmentalists see benefits, saying wood plants could reduce the use of fossil fuels, produce energy from a sustainable source and offset carbon dioxide emissions, the main cause of global warming. But the design and operation of the plants is crucial, they say. The advantages can diminish, depending on how the plants obtain wood, whether new trees are planted to replace it, and whether stained or pressure-treated wood - which contain toxins - is used.

"It has a lot of potential, but it has to be done right," said Daniel Sosland, executive director of Environment Northeast, a regional group focused on energy, air quality and climate change.

The amount of available wood to use as fuel is an issue. Because there are no existing wood-fired plants in Connecticut, industry officials say they're using estimates for the wood supply and its cost.

"The question is, will there be financing for a project like this?" said Joel Rinebold, a principal in Clearview Renewable Energy, which is developing a biomass plant in Bozrah. "We believe there will be, but if a question of wood supply comes up, and if too many projects have been approved, the results may be banks may not finance one or all of the projects."

Wood In, Power Out

Plainfield Renewable Energy is proposing the largest plant - for 37.5 megawatts - at the site of an old quarry in Plainfield.

The Tamarack Energy project, known as GDI Renewable Power, is proposed in Watertown.

The Clearview project in Bozrah is a little different. It proposes to use wood mixed with chicken manure produced daily at the nearby Kofkoff Egg Farm. The project will not only supply energy, but also give Kofkoff, one of New England's largest egg producers, a way to address growing problems with disposing of the 340 tons of manure it produces daily, Rinebold said.

The technologies for the plants are similar. Basically, wood chips are loaded into a boiler, where they are heated to create a gas. The gas is then ignited to create steam, which turns a turbine to generate electricity.

Because wood has a high water content, it takes massive amounts of chips to create energy. The Watertown plant, for example, would use 300,000 to 400,000 tons of chips annually.

Developers say that, in many cases, the chips would come from wood that otherwise would end up in landfills. That includes stumps, tree trimmings from utility and municipal crews, clearing for new construction and old cargo pallets. The Plainfield plant is planning to use debris from construction and demolition, as well.

Getting additional fuel from forestry management projects is also being discussed. Carter, of Tamarack Energy, said the number of woodland projects that can be done is limited because the trees and other trimmings are difficult to dispose of. Wood power plants could change that.

Done properly, forestry work can improve tree growth, expand animal and plant habitats and reduce the danger of fire, said Professor Chad Oliver, director of Yale University's Global Institute of Sustainable Forestry.

"There is large potential to thin the forest and use some of the smaller material for energy," he said.

But it's clear that using wood for electricity will not, by itself, answer the state's energy needs. A 2000 study for the Clean Energy Fund estimated that the state could support about 100 megawatts to 300 megawatts of wood-fired energy production - enough for 75,000 to 300,000 average homes. That's a small fraction of the state's needs. For instance, in the summer, demand can climb to 7,000 megawatts or more.

Economics Of Wood

Although much of the wood the plants would use is unwanted, it does carry costs.

There is the expense of getting it, chipping it and transporting it to the plants. Then, if a demand is created, the chips could take on value as a commodity, further adding to costs.

Right now, fossil fuel costs and government incentives are making the economics of wood-fired plants work and stimulating investment. The last time there was strong interest in wood was nearly 20 years ago, when projects were considered for several municipalities, including Torrington.

"People see the economics and are highly motivated to make these plants happen," said Daniel Donovan, vice president of Plainfield Renewable Energy.

What makes the economics attractive is the Clean Energy Fund's "Project 100," a state-sponsored program funded by ratepayers to foster new renewable-energy projects.

Under the program, the wood projects would get long-term energy contracts, which is crucial when construction costs can run to $100 million or more. Project 100 also provides additional payments of as much as 5.5 cents per kilowatt hour, helping to make the projects viable, said Lise Dondy, executive director of the Clean Energy Fund.

The Watertown project has already received the fund's backing for a contract for half its electricity. It is competing for additional contracts with the Plainfield and Bozrah plants, as well as with 27 other fuel cell, wind and solar projects. The fund is expected to announce its latest round of finalists Monday.

If the wood projects are chosen, the next step would be environmental permits. The state Department of Environmental Protection says wood plants must adhere to the same emission regulations as other power plants. Because the wood is being burned, the process emits particulate matter and various greenhouse gases.

All three plant developers say the plants would have technologies in place to clean the emissions as they leave the smokestack. Donovan says the plant in Plainfield would be the cleanest of its kind in the country.

But the process is based on combustion, so wood plants do emit pollutants, including nitrogen oxide, a contributor to air pollution, DEP officials said. The plants also emit carbon dioxide, a substance that is not currently regulated, although there has been much discussion about how to reduce that particular greenhouse gas.

Plant developers point out that the wood they use would inevitably produce carbon dioxide or worse, methane - whether burned in their plants or left to rot in landfills or forests.

But for the process to work best, Derek Murrow, director of policy analysis for Environment Northeast, says a complete cycle has to be established of harvesting wood, releasing carbon by burning it, and then growing new trees that would recapture the carbon dioxide as part of photosynthesis.

Joel Gordes, an energy consultant and former legislator who has studied the use of wood in plants, said another issue regulators must watch for is the wood that's going into the facilities. If construction waste becomes the main source of fuel, it could turn public opinion against the plants and discredit them as a renewable-energy source, even if there's just the perception that dangerous chemicals found in such debris are being burned with the wood.

"It could set it back 30 years, in my opinion," Gordes said.Hartford Courant