When discussing renewable energy, you’re likely to hear a lot about wind, solar, geothermal and even hydropower. Heck, you’re likely to see the conversation turn to nuclear power (not renewable, by the way) before anyone mentions one of our oldest and humblest renewable sources of energy – wood.
But the good old American log – the energy provider of choice in the United States before coal became king in the 1880s – could make a comeback as the hottest renewable around.
According to an article in Science from researchers at The Nature Conservancy, Duke University, Resource Professionals Group, USDA and the Austrian Chamber of Agriculture, advanced wood combustion (AWC) facilities could help the United States
Here’s how it works:
Localizes energy production
The first step is to give up the idea of a power plant off in the distance providing juice to your home through miles of power lines. That is so 20th century – like what they did before hybrid cars. What we need is a more localized energy system that provides power to communities from within the community over short distances.
This can work through AWC, the authors say, because the systems release minimal amounts of sulfur oxides, mercury and other pollutants. It turns out wood is much cleaner than coal. Modern AWC facilities – common in Europe – also approach 90 percent thermal efficiency.
To get even more juice, communities can combine AWC with solar, wind or geothermal power and actually sell power back to the grid.
AWC provides lower emissions through efficiency — efficiency in burning and transmission. Because the energy doesn’t have to travel as far, you get more bang for the log. AWC also takes advantage of CO2 that’s already in the system, recirculation CO2 already in the biosphere’s carbon cycle. Fossil fuels, on the other hand, introduce more CO2 into the system when they are burned.
If communities get smart about AWC, they’ll have to build new facilities and reconfigure transmission lines – both of which would create jobs. There will also be new employment and training opportunities for electricians, steamfitters and plumbers (not to mention foresters) to ensure that this new source of power doesn’t diminish our forests.
Forest management is the key to making AWC work. Fuel for these plants must come from sustainably managed forests and through activities like fire thinning and general forest maintenance. This is not only essential for the ecosystem, it’s also essential for the AWC plant – it’s useless without a sustainable supply of wood to feed it.
But the wood doesn’t need to come from forests alone. The researchers point out that the United States produces 30 million tons of combustible urban wood a year from storms and construction site debris. That material is often thrown in a landfill, but could be used to produce energy for urban areas.
In downtown St. Paul, Minnesota, for example, a retired coal plant converts 250,000 tons of urban wood a year to cleanly generate heat, cooling and power – right from the downtown.
So, the next time you’re talking renewable energy – don’t forget the miracle of wood.
(Image: Long Hope Creek in the Southern Appalachian region of North Carolina. Credit: TNC.)