From blogs to The New York Times, much is being said about the carbon impact of using wood for energy—without much distinction between using it for heat or electricity generation. Yet when it comes to carbon, they are worlds apart.
Fully accounting for the carbon impact of using wood as fuel is very complicated, and blanket statements that assume all energy from wood is equal are ignoring critical distinctions between wood as a heating fuel, and wood used to generate electricity.
The Northern Forest Center specifically champions modern wood heat because—in the context of the Northeast—generating heat from wood via highly efficient primary heating systems is a triple winner, producing reliable, local fuel at a stable price; saving money and creating jobs for rural communities; and reducing net atmospheric carbon dioxide over time. Ideally, wood heat is sourced and produced close to where it is used, at a scale that fits within the carrying capacity of the region’s forests.
The Center advocates for the Northern Forest, its people, and its communities. We’re not an industry group, nor do we have a financial stake in the wood energy industry. Our focus is building sustainable economic opportunities that benefit the region, and we believe that heating with wood pellets and wood chips is a winner for our economy, environment, and people.
There is a carbon cost to using all types of fuel (even the cost to manufacture and ship solar or geothermal equipment). Compared to any fossil fuel, modern wood heat comes out way ahead in carbon accounting.
Using wood for energy releases carbon stored in the wood as carbon dioxide, but new trees will reabsorb carbon as they grow. The difference between the amount of carbon released and the amount reabsorbed by the trees that grow back is known as “carbon debt.” To measure how much carbon debt comes from using any fuel for heat or electricity, every one of the following factors must be accounted for:
- Carbon emitted by the fuel being used
- Efficiency of the heat or electrical generation system being used
- All the carbon costs associated with producing the fuel (including extraction or harvesting, manufacturing or processing, transportation)
- The regrowth rate of the forest (in the case of using wood for fuel)
That last point is critical when comparing wood heat to fossil fuel heat. Trees will reabsorb carbon from the atmosphere, but no fossil fuel can do that. Fossil fuel took millions of years to form from organic material and there is no way to “pay back” this enormous carbon debt within a meaningful timeframe. In contrast, forests grow back in the span of a human lifetime (or less) and reduce the carbon debt of using wood for fuel as the trees grow.
Wood heat in particular has a fast payback. One reason wood heat performs so well is because wood-fueled heating systems are up to 90% efficient. The up-front efficiency of wood heat creates a much smaller carbon debt than the less efficient systems used to generate electricity from wood.
Studies such as one released in 2010 by the Manomet Center for Conservation Sciences have reached positive conclusions about using wood for heat, yet media coverage tends to focus on the much higher carbon impacts of using wood for electricity and fails to distinguish between the uses. And most press coverage fails to explain the additional benefits—beyond carbon reduction—of using wood for heat.
Other renewable energy sources and increased energy efficiency of homes and buildings may result in lower carbon emissions, but carbon savings alone are not the only benefits of modern wood heating. In the heavily forested Northeast, modern wood heat delivers significant benefits in addition to a very low net carbon impact:
- Modern wood heat creates new forest-based jobs and keeps money circulating in our local and regional economy. Most of New England sits inside the largest forest east of the Mississippi, yet we use the vast majority of the home heating oil consumed in the US, and according to data from the federal Energy Information Administration, 78 cents of every dollar spent on heating oil leaves our region’s economy. When people buy local wood pellets or chips sourced and manufactured here, that money stays in the regional economy, generating a very positive economic bonus through savings, direct spending and the ripple effect of money staying in the local economy.
- Modern wood heat provides markets for lower-grade wood which help landowners improve forest quality and sustain forestland as forests. Here in the Northern Forest, most wood used for modern heating systems is a byproduct of harvests that happen as part of ongoing forest management, not as the primary reason for the harvest.
Considered in total, the benefits of modern wood heat are significant to the Northern Forest region: fuel cost savings for homeowners, businesses, municipalities and others; a positive economic impact on the region; new forest-based jobs; an important market for lower-grade wood from sustainably managed forests; increased energy self-reliance; and reduction in net carbon dioxide in the atmosphere in as little as five years.
Visit our online dashboard to see our progress to date in realizing these benefits for the region.