REA News: Biomass sustainability22/02/2013
Despite the polarised reports, good forestry practices and biomass power can go hand in hand. Paul Thompson says sustainability criteria is key to delivering widespread benefits.
Everyone agrees that sustainability is key to widespread use of bioenergy. But the casual observer might be feeling a little confused by now. For example, at the end of 2012, two separate and diametrically opposed reports surfaced. The first, from three leading environment NGOs, claimed that a widely supported renewable fuel was in fact far dirtier than burning coal, the most polluting of all fossil fuels. The other report, by a professional services consultancy, noted that the same fuel was greener, cheaper and should be rolled out even further than already planned.
Both followed hot on the heels of an Ofgem warning that the UK's energy supply is soon to run dangerously close to full capacity, with lights going out by 2015. The debate is urgent: with the EU ordering the shut-down of our last few coal-fired power stations, how do we plug the gap? Where do we find a cheap, sustainable fuel to keep the lights on?
Step forward biomass - converting organic materials into energy. There are many types of biomass, but this particular debate centres around wood and forestry. Much of the attention is currently focussed on the use of biomass in power, although it is clear that many of the issues involved are also relevant to some degree for heat.
The off-cuts and residue of trees and plants that would otherwise be swept from the saw mill's floors and disposed of as waste or left on the forest floor can be used as fuel. Whereas the valuable (and expensive) trunk of a tree might go to the timber yard and eventually become housing or furniture, the lower value material can be used for energy. Almost none of the tree goes to waste, encouraging landowners to view forests as profitable - worthy of investment and expansion. Coupled with sustainability rules that require power generators to buy from well-managed forests and agricultural producers, the system forms a virtuous circle, as carbon released into the air by the combustion of biomass is reabsorbed by replacement trees and plants.
Forests both in the UK and internationally are currently undermanaged. Admittedly, you'd be forgiven for thinking that means wild, unkempt, 'born free' forestry as nature intended. In fact, as the Forestry Commission points out, unmanaged forests have lower biodiversity. Fallen trees lie diagonally where they fall, and eventually rot down releasing their carbon back into the atmosphere as CO2. Unmanaged woodlands are also prone to disease, wildfires, and infestations. In short, they're less robust and have stopped being net absorbers of carbon.
But the key point is this: you can replant a tree but you can't replant coal (at least not yet - industrial-scale carbon storage is a rather faltering aspiration). The carbon released into the atmosphere by a tree can be reabsorbed by its replacement, making this a way to keep atmospheric carbon levels stable. Burning coal releases carbon into the air that would have otherwise stayed in the ground for several million years more.
Even more precarious than unmanaged forests are forests whose owners can't make a profit. Landowners need to make a living from their land and, if forests won't do it, they may sell for development or agriculture. The impact of this type of deforestation in South America is huge. So anything that pushes up demand for sustainable biomass is crucial for maintaining and enhancing forest cover.
Key to all this is the sustainability criteria - including factoring in the supply chain from seeding to processing to shipping. The UK is leading the way on this. But also essential is a thriving industry that has the confidence to invest. That needs Ministers to offer long-term assurances that they won't move the goalposts from year-to-year. But if that can be achieved, the lights can stay on and we won't need coal to do it.