Study finds wood burning releases more greehouse gas than coal

Last year the state of Massachusetts suspended licenses for new wood-burning power plants and commissioned a study on the environmental impacts of burning wood for electricity. That study, conducted by the Manomet Center for Conservation Sciences, has now been released and it shows that, per unit, wood releases more climate-damaging gases than coal.

Ian Bowles, the Massachusetts Secretary of Energy and Environmental Affairs, told the Boston Globe that the findings have broad implications for clean energy and the environment in Massachusetts and beyond.

Wood burning has been promoted as a “green’’ energy source because growing forests can absorb the same amount of greenhouse gases that are emitted from burning wood, essentially canceling out the pollutants.

But the Manomet study shows that wood burning releases more heat-trapping carbon dioxide into the atmosphere per unit of energy than oil, coal, or natural gas.

What’s more, that increase in greenhouse gases can take a far longer time for forests to absorb than previously thought — a generation or more in many cases. If a wood-burning power plant replaces a coal-fired one, it can take about 20 years before any net benefits are realized. It can take more than 90 years if a wood-burning plant replaces a natural gas plant.

The study also found that there would not be enough sustainably harvested wood available to power even one biomass plant in Massachusetts

Michigan’s 2008 renewable energy law provides incentives for the development of wood-fired power plants, and several are in the planning stages here.

At hearings about proposed wood-fired plants in Traverse City and Mancelona, concerned citizens have questioned the carbon neutrality of wood burning and raised concerns about the potential impact on regional forests and air quality.