Should we burn trees for energy?
As the European Union Parliament debates changes to a directive on renewable energy, more than 650 scientists have signed a letter demanding an amendment to the directive’s definition of forest biomass.
Under the current definition, nations and industries can count as ‘renewable’ the energy sourced from burning trees that were cut down just for that purpose. The letter from scientists states that only the forest biomass from residues and waste left by trees cut down for other purposes should count toward the EU target of at least 20 percent renewable energy by 2020. The signatories warn that a failure to make this change will continue to put global climate goals, and the world’s forests, at risk.
Robert Nasi, Director General of the Center for International Forestry Research (CIFOR), agrees in principle with the letter, but says the reality of forest biomass supply chains and carbon dynamics is even more complex than the letter’s argument makes out.
Ahead of a vote by the Parliament in Strasbourg this week, Forests News caught up with CIFOR’s DG to hear his views on why further study is needed to inform policies on forest biomass as a form of renewable energy.
The EU Parliament is about to discuss changes to a Renewable Energy Directive that includes forest biomass as a renewable energy source. More than 650 scientists have signed an open letter opposing elements of the Directive. What’s the issue here?
This whole issue of wood for energy is quite interesting and it’s been a topic on the international agenda for a long time. In the carbon accounting system of the European Commission, it’s considered that if you burn wood to produce energy, it’s carbon neutral. If you burn coal, you have to declare a certain amount of greenhouse gas emissions.
There are several issues. One is the fact that it’s not carbon neutral – or it’s a bit more complicated than it looks.
This is a complex problem because it involves time, including recovery time for plantations; it involves scale, in terms of the landscape and in terms of transportation; and it involves economics, in terms of what makes sense financially for a company to produce and to export.
The scientists’ letter backs the use of wood waste and residues for fuel, but opposes cutting down forests to burn them for energy. What’s your stance on this?
I’m personally sympathetic to the idea, because I think that cutting natural forests for wood energy is a ‘no-no’. Transporting wood pellets or wood chips across the Atlantic is also a ‘no-no’. But I’m personally not willing to sign because I also think there are good climate change gains to make in repressing coal via properly used wood energy.
In this letter, it’s not clearly defined what you can do using residues and waste. Some studies show that even with residues you can have a very beneficial or a very detrimental result. They don’t really consider the whole issue of existing plantations, fast-growing plantations, and they don’t look, I would say, at the complete process from an evidence base. That’s why as a scientist, I’m not willing to sign.
The other problem I have is that it sends an overall message that wood energy is bad. When in fact this is based on a very specific example. And I don’t think it’s true.
What’s the difference between using residues and waste as fuel, and cutting down forests to burn them?
When you burn wood, because it comes from a renewable resource — it’s the trees that are fixing carbon into their trunk, leaves, branches — then actually you are not adding carbon to the atmosphere. So people assert it is carbon neutral. There are two main problems with that. One is the fact that you need to emit greenhouse gases to cut the wood, to transform it.
Even with residues, some studies — depending on the processing chain used — show that these can have 83% less greenhouse gas emissions than coal, or 72% more. This is with the same residues from the same forest, depending on how you treat them, how you transport them, and how you dry them. So even with residues, it is not that simple.
A second point is the time issue. If you cut a standing tree, you’ll have a time debt. It may very well be that it will become carbon neutral, but in a hundred years from now. So you are suddenly adding a huge amount of greenhouse gases to the atmosphere, that will eventually be recovered by the growth of the vegetation, but one hundred years later.
If we are aiming to change the climate now, it is not going to happen. It’s going to be too late.
So these are some of the main issues. Another one, which I find totally unacceptable, is the fact that we are transporting wood pellets from the United States to the United Kingdom. And people tell you, ‘Oh, this is economically viable because shipping is so efficient’. In fact, it costs less money to ship pellets from the US to the UK than to transport them by road for 50 or 80 kilometers. So you save money, but you don’t take into account all the externalities, all the carbon embedded in your transportation.
I think this letter, this issue, is mixing a lot of different issues and it’s much more complex that people want to believe it is. And it’s the same case for the European Union’s Renewable Energy Directive. It’s an oversimplification. So what would be the proper way, I think, is for the Directive to provide a framework to ensure that if we use wood energy, this wood energy is sustainable and effectively ends up emitting less greenhouse gases than carbon within a well-defined timespan.
What do you suggest as a better way forward?
It’s good to have someone keeping the decision-makers on their toes, in terms of making sure that all the elements are taken into account. But for me, this letter from scientists belongs more, in this case, to advocacy rather than science. Because the science on this is not that clear. That’s the main issue I have.
I think what we need to have is a proper study. And not one carried out under a completely conservation-oriented agenda, or under the agenda of the wood industry, but by a neutral agency. We really need to have a proper study on the various supply chains — not only for forest biomass, but for others as well — and then we need to have a real discussion between scientists and the policymakers to put together a better directive.
via CIFOR Forests News http://ift.tt/2xsQew9