It’s obvious that burning trees for heat or to create electricity is better from a greenhouse-gas point of view than burning coal and oil, because the trees can regrow and pull back the the carbon they released into the air. Or maybe it’s not so obvious, reports UnDark, a new magazine from MIT:
The report takes issue with two major assumptions on biomass: 1) That burning wood for electricity production reduces planet warming emissions compared to coal, and 2) So long as new trees are planted to replace the biomass that’s being burned, net emissions from biomass power are basically zero. But those claims are too simplistic, some scientists say.
The problem is that it takes years for regrowing trees to absorb any sizeable proportion of the carbon released quickly when they burn. Studies say that if the biomass isn’t collected well – if biomass companies rampage through established forests for their product – the carbon cost is very high for many years, if not longer. If we mow down all our forests to create electricity, it might even be worse for the atmosphere than drilling more oil and leaving the forests alone.
The problem isn’t really that biomass energy is worse for greenhouse gas emissions than fossil fuel-powered energy, it’s that badly-done biomass energy can be worse. Corporate transparency is important.
Thought provoking but completely agree.
Perhaps we need to pay more attention to specialty crops, grown and harvested for this exact purpose (King Grass, Elephant Grass, Arundo, etc.).
On the other hand, New England already has an infrastructure for planting, growing and harvesting trees, a lot of knowledge of how it can be done, experience with building power plants that can burn chips or pellets, and a lot of research institutions that are studying the system. It seems silly to reinvent the whole thing with a different type of plant; wouldn’t it be better and easier to improve the current system?
This has come up multiple times in the past so I never know how to respond.
The first question that needs to be addressed is how much CO2 gets released burning wood compared to coal, oil, or natural gas? Even if trees do not regrow (unlikely here in NH) if the CO2 emission of wood is less then fossil fuel we already come out ahead. It is true burning wood releases the the CO2 quickly but so does burning anything.
We just had a thinning cut done on our property. The harvested wood will become lumber and the tops/scraps burned for electricity. The remaining trees, now exposed to more sunlight grow faster, continuing to capture CO2. It is my understanding the more open environment makes for significantly better animal habitat, and with different lighting plant micro-ecosystem.
So I guess like any activity you can do it stupidly or smart. We have lived on our property for 35 years. In all that time we heated with wood, about 3-cords a year. I have to assume (know what they say about assume) our carbon footprint is much lower then if we heated with fossil fuel.
Wood pellets have been used for years to heat homes from small local pellet mills with an average capacity of 20,000 tons per year. Biomass includes wood pellets along with many other products. The questions are not about biomass, but Enviva’s export pellet problems.
Enviva has created a whole new export industry with a massive supply chain and massive wood pellet mills with an average capacity 500,000 metric tons per year. Enviva has an army of loggers, forest owners, truckers, railroads, storage facilities, export ports, shipping containers, etc. Enviva is working with the U.K. Drax to keep a 35-year-old 4,000-megawatt coal-fired power station alive.
The Enviva website says: “Enviva owns and operates six plants that are strategically located in the southeastern United States producing about 2.2 million metric tons of wood pellets annually. We export our pellets primarily to power plants in the United Kingdom and Europe that previously were fueled by coal, enabling them to reduce their carbon footprint by about 80 percent.”
An 80 percent carbon footprint reduction is an illusion. It has been called “an accounting error” by some, and other names by independent thinkers.
Let’s do an experiment. Go to your bank and ask for a $1 million unsecured loan, payable in 100 equal installments of $10,000 per year. If your bank uses Enviva pellet-math, you will walk out with $1 million!