Current biomass policy frameworks are not fit for purpose and require substantial changes to ensure they contribute to mitigating climate change rather than exacerbating it.
Accounting for biomass carbon emissions
The second assumption that leads to the perception that biomass energy is zero-carbon at the point of combustion derives from the international greenhouse gas reporting and accounting frameworks established under the UN Framework Convention on Climate Change (UNFCCC) and the Kyoto Protocol. In order to avoid double-counting emissions from biomass energy within the energy sector (when the biomass is burned) and the land-use sector (when the biomass is harvested), the rules provide that emissions should be reported within the land-use sector only.
While this approach makes sense for reporting, it has resulted in significant gaps in the context of accounting – measuring emissions levels against countries’ targets under the Kyoto Protocol (or, potentially, the Paris Agreement), largely deriving from the different forest-management reference levels that parties have been permitted to adopt. The problem of ‘missing’, or unaccounted-for, emissions arises when a country using biomass for energy:
- Imports it from a country outside the accounting framework – such as the US, Canada or Russia, all significant exporters of woody biomass that do not account for greenhouse gas emissions under the second commitment period of the Kyoto Protocol;
- Accounts for its biomass emissions using a historical forest-management reference level that includes higher levels of biomass-related emissions than in the present; or
- Accounts for its biomass-related emissions using a business-as-usual forest-management reference level that includes, explicitly or implicitly, anticipated emissions from biomass energy (since the associated emissions built in to the projection will not count against its national target).
This risks creating perverse policy outcomes. Where a tonne of emissions from burning biomass for energy does not count against a country’s emissions target but a tonne of emissions from fossil fuel sources does, there will be an incentive to use biomass energy rather than fossil fuels in order to reduce the country’s greenhouse gas emissions – even where this reduction is not ‘real’ in the sense that it is not accounted for by either the user or the source country.
The quantity of emissions missing from the international greenhouse gas accounting framework is impossible to calculate precisely. Forest-management reference level submissions do not contain sufficient information on the quantity of woody biomass projected to be used, the origins of that biomass (additional domestic forest harvests, increased use of domestic forestry residues or higher imports) and the resulting emissions. Nevertheless, the quantity of emissions is likely to be significant, as demonstrated in several country case studies.
In 2014, countries listed in Annex I to the UNFCCC in aggregate emitted 985 million tonnes of carbon dioxide (MtCO2) from biomass combustion, including an estimated 781 MtCO2 from solid biomass. The latter figure is equivalent to 5.6 per cent of aggregate, economy-wide carbon dioxide emissions from Annex I countries in 2014, and 6 per cent of their total energy emissions. The US accounts for almost 28 per cent of total Annex I solid biomass carbon emissions, while Germany, Japan and France account for a further 26 per cent. Neither the US nor Japan account for emissions from their land-use sectors under the Kyoto Protocol, while Germany accounts against a business-as-usual projection that does not explicitly include bioenergy policies, and France uses a business-as-usual projection that includes bioenergy demand from policies up to, but not including, the EU Renewable Energy Directive. Woody biomass emissions from all these countries, therefore, have the potential to go unaccounted for.
Recommendations
Four steps could be taken within the existing framework to reduce the potential for missing emissions:
- All parties to the Kyoto Protocol and the Paris Agreement should include the land-use sector in their national accounting.
- Forest-management reference levels should contain detailed information on projected emissions from using biomass for energy, the origins of that biomass (additional domestic forest harvests or increased use of domestic forestry residues) and the resulting emissions.
- Countries that import biomass for energy should be required to report on whether and how the country of origin accounts for biomass-based emissions. Emissions associated with biomass imported from a country that does not account for such emissions, or from one that has built biomass energy demand into its accounting baseline, should be fully accounted for by the importing country.
- Countries using domestic biomass for energy should reconcile their energy and land-use sector accounting approaches in order to put emissions from each sector on a par with each other, if possible through using the same benchmarks – either a historical reference year/period or a business-as-usual scenario – to avoid emissions leakage between the sectors. This should be uniform across all countries.
If the land-use accounting rules are not reformed as suggested above, a more radical option would be to account for carbon dioxide emissions from biomass burned for energy within the energy sector, with additional rules to avoid double-counting in the land-use sector.
Sustainability criteria
One means of avoiding, or at least ameliorating, the impacts on the climate of the use of woody biomass for energy is to apply preconditions that biomass installations are required to meet before they are eligible for the regulatory and financial support afforded to renewable energy sources. The European Commission published proposals for sustainability criteria for solid biomass in late 2016. Many EU member states already apply some criteria; the most detailed have been developed in Belgium, Denmark, the Netherlands and the UK.
In general these have two components: requirements for minimum levels of greenhouse gas savings compared to fossil fuels, and requirements (often called ‘land criteria’) relating to the legality and sustainability of forest management, usually taken from national timber procurement policies. Sometimes other criteria, such as restrictions on types of feedstock or on minimum plant energy efficiency levels, are also included. However, none of these systems includes changes in levels of forest carbon stock in their calculation of greenhouse gas savings (apart from direct land-use change), though the Dutch criteria contain a requirement that the forest is managed with the aim of retaining or increasing carbon stocks in the medium or long term, and the EU proposed criteria include a requirement for the country from which the forest biomass is sourced to be a party to the Paris Agreement, which accounts for changes in carbon stock associated with biomass harvests.
Several voluntary certification schemes have developed with the aim of including climate impacts alongside other criteria, such as sustainable forest management. The main one is the Sustainable Biomass Partnership (SBP), established in 2013 by seven major European utility companies. Its standard includes the need to define the supply base of the biomass, to ensure feedstock can be traced back to its source area, and a requirement that ‘regional carbon stocks are maintained or increased over the medium to long term’. The standard includes a calculation of the energy and carbon balance of the biomass used for energy, but this does not include changes in forest carbon stock. Verification involves a regional approach that uses a desk-based assessment against the criteria leading to a risk rating for each indicator. Where risks are identified, appropriate mitigation measures must be defined, implemented and monitored.
These schemes’ failures to account, comprehensively or at all, for changes in forest carbon stock mean they cannot be considered as satisfactory. Effectively, their criteria permit the provision of financial and regulatory support to policy options that could increase carbon emissions in the short and medium term, and possibly in the long term too. The references to forest carbon stock in the Dutch and SBP’s criteria are too vague. Forest carbon stock levels may stay the same or increase for reasons entirely unconnected with use for energy. The important issue is what levels they would have reached in the absence of biomass energy use. Similarly, the requirement in the proposed EU criteria for land-use sector accounting in the country of origin to take account of changes in forest carbon stock is a step in the right direction. It is still subject to the flaws identified earlier, however, and cannot take account of the full climate impact of the use of forest residues, which may be significantly underestimated in current models, given the potential effects on soil carbon levels and tree growth rates.
To date, no national biomass sustainability standards have been developed outside the EU, though the US state of Massachusetts restricts eligibility for subsidies based on net carbon accounting over a 20-year timeframe, and includes sustainability provisions such as the requirement that harvests leave sufficient woody material on the forest floor to replenish soil nutrients and protect wildlife. In addition, biomass plants must demonstrate emissions reductions over time on the basis of life-cycle emissions analyses, including a carbon-debt emissions factor, and must satisfy a minimum efficiency level.
Recommendations
- Robust sustainability criteria must deal with the impact on greenhouse gas emissions and the legality and sustainability of forest management.
- One option would be for the greenhouse gas element to be underpinned by a comprehensive life-cycle analysis for each type of feedstock, including changes in the forest carbon stock alongside supply-chain emissions. However, this is a complex calculation depending partly on the counterfactual (what would have happened to the wood, and the forest from which it was sourced, if it had not been used for energy?) and difficult to implement in real life.
- A more practical approach is to restrict eligibility for support to those feedstocks that are most likely to reduce net carbon emissions (or have low carbon payback periods): primarily mill residues, together with post-consumer waste. An additional element could be a requirement for a minimum level of efficiency of the unit in which the biomass is burnt.
- Policies should also ensure that subsidies do not encourage the biomass industry to divert raw material (such as mill residues) away from alternative uses (such as fibreboard), which have far lower impacts on carbon emissions.
- Alongside these emissions criteria, land criteria for legal and sustainable sourcing should be used to protect the way in which the forests are managed. Risk-based assessments of areas lacking coverage of forest certification schemes should supplement desk-based assessments with on-the-ground inspections.