“Woodfuel is good,” says Gordon Watts (Avoiding a biomass battle). “It’s carbon neutral, because the carbon that it emits when burned has been absorbed by the tree during its lifetime.”
Whoops! Woodfuel is not good because it burns carbon stored in the tree and releases it to the atmosphere as CO2. If this is our objective then we should burn coal because we get more kW per kg of CO2 emitted from coal than we do from wood.
What is good is replacing the tree you have burned with a new tree in the forest so that you can recycle the CO2 produced. The virtuous part of the cycle is growing trees, not burning wood. If you don’t renew and replace the forest you would be better burning coal.
All the current Renewable Obligation Certificate incentives are for burning wood. These subsidies dwarf incentives for planting trees. And worse than this, the tree-planting grants are skewed heavily towards hardwoods and native pinewoods. Highly productive softwood forests are being felled and replaced with non-productive conservation woodlands that will produce very little timber or fuel, and capture very little carbon in their lifetime. The net result is a loss of carbon from the forest.
No substantial new commercial forestry planting has taken place in the last 30 years since the withdrawal of tax relief. This is the exact opposite of what renewable policy should be trying to achieve, and it is not sustainable.
ROCs should be limited to power produced from waste wood at the end of its life cycle and forest residues unusable for any other purpose. The money saved should be diverted to forest creation and replacement, emphasising fast-growing commercial softwood species. This way we can have an increasing source of raw material for our forest industries, capture carbon, and still produce some power from wood at the end of its life cycle. Government policy should promote planting before burning.
PG Blake
Munro Sawmills Ltd