Bioenergy has often been touted as a key part of our low-carbon future. However, there are many complex and interrelated issues that need to be explored and responded to before we increase our investment in this controversial technology.
Concerns
On an international level, food security, water scarcity and the loss of biodiversity all need to be addressed.
It is important that the UK takes these impacts into consideration as the demand for biomass is on the rise with 42 new power stations currently under proposal. It should be noted that one third of the UK’s biomass is imported, with the government estimating it will have to import 80% of wood to burn by 2020. Wood pellets are currently being shipped to the UK from biodiverse and carbon rich forests in North America.
Many biomass developers say they will only burn waste wood, which includes forest residues from UK sources that could not otherwise be used. However, there is clear evidence from US conservation group Dogwood Alliance that whole logs and trees are being chopped down to be processed into wood pellets to serve the UK market. Moreover, the Natural Resources Defence Council has published evidence that the Drax Group’s (a power generation company) pellet supplier is targeting rare wetland forests in North Carolina.
There are also concerns over the impact of biomass on climate change. Per unit of energy produced, smokestack CO2 emissions from biomass power stations are on average 50% higher than those from coal fired power stations. This carbon debt is only paid back if and when a tree or crop is fully grown to replace what was cut down and if soils and other vegetation re-absorb the carbon they lost. However, this may take decades or even centuries.
Finally, there are additional concerns over the efficiency of biomass plants.
Implications for UK 2020 renewable energy target
Currently, the UK has just 5.2% of final consumption from renewable energy. In order to meet our target of achieving 15% of energy consumption from renewable sources by 2020, a diverse range of low carbon technologies are required.
There is no silver bullet technology. For example if we were to rely solely on offshore wind an extra 50GW of installed capacity would be required in addition to the current 10.5GW capacity. If we were to just rely on solar PV, 42 million homes would need to be fitted with solar panels (including 12 million homes not yet built). And if we were to rely just on biomass, an extra 40GW of generating capacity (equivalent to another 11 Drax power stations) would be required.
So a mix of low carbon technologies is necessary if the UK is to achieve its 2020 renewable energy target and biomass (which is classified as “renewable”) can play a part in achieving this goal, so long as the following recommendations are taken into account.
Recommendations
Only ambitious GHG and energy efficient bioenergy pathways should be supported after taking into account both direct and indirect emissions associated with bioenergy production, including those from transport emissions from imported biomass.
Moreover, bioenergy production should not be established through the conversion of ecologically important ecosystems and improvements are needed to the UK government standards under which “only sustainable biomass will be subsidised”. Subsidised biomass is supposed to deliver at least 60% greenhouse gas savings compared to fossil fuels, but when calculating these ‘savings’, the CO2 emissions from burning the biomass are ignored.
Finally, all actors involved in bioenergy development should monitor the relationship between bioenergy targets, access to food and water scarcity.
Thurstan is an experienced environmental commentator, having spent many years working in the climate change & sustainability arena within a variety of top tier academic, non-profit and corporate settings. He currently works as a Senior Analyst at IDEAcarbon, writing daily articles on the latest developments in the global carbon markets, climate finance and the UNFCCC negotiations. Previously Thurstan worked as a Policy Analyst for The Climate Group (a leading climate change NGO) where he wrote regular articles on international climate policy, drafted speeches for external partners such as the Rt Hon. Tony Blair & former BP CEO Lord Browne and managed the organisations relationship with a variety of corporate sponsors (including Barclays, Marks & Spencer and Cadbury). Before that Thurstan worked in a research and project management capacity for the University of Cambridge Institute for Sustainability Leadership.