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Campaigns questioning the use of woody biomass for energy are missing key facts – IEA Bioenergy TCP

There are concurrent media campaigns and publications questioning the use of woody biomass for renewable energy production. However, as the International Energy Agency (IEA) Bioenergy Technology Collaboration Programme (IEA Bioenergy TCP) highlights, several of them misrepresent on-the-ground forestry practices and bioenergy systems, and associate the use of woody biomass for energy with overexploitation of forests, even permanent deforestation, and "the burning of trees".

Japan is a forest rich nation with an around 25 million hectare (ha) estate. However, annual harvesting volumes are only one-sixth of annual increment due to steep terrain and a lack of forest road infrastructure that make domestic roundwood expensive compared to imports. Japan joined PEFC in 2014 and its Sustainable Green Ecosystem Council (SGEC) national forest certification system was endorsed by PEFC International in June 2016.

Several media campaigns questioning the use of woody biomass for renewable energy production are misrepresenting on-the-ground forestry practices and bioenergy systems, and associate the use of woody biomass for energy with overexploitation of forests, even permanent deforestation, and “the burning of trees”. Forest bioenergy is an integral part of the forest sector that responds to bioenergy demand by devising forest management approaches and industrial processes to produce fuels, heat, and electricity along with sawlogs, paper, and a multitude of other biobased products. Further, it is well-recognized that any harvesting of biomass – be it for bioenergy, construction material, paper, or other use – should occur within sustainability boundaries. This implies management and harvesting principles providing safeguards against overharvesting and maintaining ecological sustainability as well as cultural and recreational values says IEA Bioenergy TCP.

As the EU’s Public Consultation on the Directive 2018/2001/EU (REDII) aimed at gathering stakeholder views on how the Renewable Energy Directive should be revised drew to a close, there has been a veritable crescendo of (social) media campaigns and publications questioning the use of woody biomass for renewable energy production.

However, as the International Energy Agency (IEA) Bioenergy Technology Collaboration Programme (IEA Bioenergy TCP), a global network on research and implementation of bioenergy, highlights, several of them misrepresent on-the-ground forestry practices and bioenergy systems, and associate the use of woody biomass for energy with overexploitation of forests, even permanent deforestation, and “the burning of trees”.

In reality, forest bioenergy is an integral part of the forest sector that responds to bioenergy demand by devising forest management approaches and industrial processes to produce fuels, heat, and electricity along with sawlogs, paper, and a multitude of other biobased products.

The media campaigns also often ignore the many steps that have already been taken towards sustainable forest management, particularly in Europe and North America. While it is certainly important to identify what is needed to ensure that biomass is produced and used in a responsible way, the misrepresentations within recent soundbites run the risk of discrediting biomass as a sustainable material and energy source altogether – a feat that could have dire consequences for global carbon neutrality ambitions, IEA Bioenergy TCP warns.

Combustion is today the most frequent means of converting woody biomass into energy, particularly in the form of heat and/or power. This can conjure the vision of “cutting down forest stands and burning the trees for energy” in the mind of readers, including scientists, that are unfamiliar with on-the-ground forestry and bioenergy systems. However, the reality is very different.

A logyard at a sawmill in Sweden. Residues such as bark, logging residues, and reject woodchips are typically used to fire a biomass heat plant that supplies heat to the dry kilns and/or a local district heat network. Woodchips from the sawmill are generally destined for pulp and paper while sawdust and planer shavings are typically used to produce wood pellets.

Forests are generally managed to provide multiple forest products, such as sawnwood, paper, bioenergy, and also other biobased products. The wood used for bioenergy is not high-quality lumber, but typically comprises thinnings, low-quality wood, salvage wood, harvest logging residues, processing residues, or wood waste.

As a case in point, about 90 percent of global renewable industrial heat consumption is currently based on biomass, mainly in industries that can use their own biomass waste and residues, such as sawmills and the pulp and paper industry. By shifting from fossil fuels to biomass these industries can stop injecting fossil carbon into the atmosphere.

Energy efficiency improvements and changes in industrial processes in addition enable them to produce fuels, heat, and electricity for use elsewhere, e.g., for heating homes.

A recent report by the Joint Research Centre of the European Commission (JRC) found that about 50 percent of the wood used for bioenergy in the EU is derived from secondary products, such as forest-based industry by-products and recovered post-consumer wood, 17 percent from treetops, branches and other residues, and 20 percent from stemwood – which is mostly coppice wood, small stem thinning wood and harvested stems of poor quality that cannot be used in sawmills or pulp and paper production.

Timber harvesting in a sustainably managed pine forest in south-central Sweden.

Further, it is well-recognized that any harvesting of biomass – be it for bioenergy, construction material, paper, or other use – should occur within sustainability boundaries.

This implies management and harvesting principles providing safeguards against overharvesting and maintaining ecological sustainability as well as cultural and recreational values. This is why in the past 30 years sustainable forest management schemes such as the Forest Stewardship Council (FSC) or the Programme for the Endorsement of Forest Certification (PEFC) endorsed schemes have been developed and deployed. Hundreds of millions of hectares of forests globally are currently certified by FSC or PEFC.

Many countries have adopted similar forest management principles in their national or regional forestry legislations. Moreover, in the European context – the focus of these media campaigns – the recast of the Renewable Energy Directive (RED) imposes further requirements to minimize the risk of using forest biomass derived from unsustainable practice.

It is critically important to recognize that carbon dioxide (CO2) emitted from bioenergy use is part of the short-term carbon cycle. When a forest stand is harvested and some of the biomass is used for energy, the carbon that was previously taken up from the atmosphere during stand growth is emitted to the atmosphere, and new carbon is taken up again when the stand regrows.  So as long as harvests do not exceed carbon uptake in the forest, it does not increase atmospheric CO2 concentrations.

In contrast, fossil fuel use causes a linear flow of carbon from geologic stores to the atmosphere. Just comparing CO2 emissions at the flue stack – as is sometimes done – misses this fundamental difference between biogenic and fossil carbon.

What matters is whether increasing the use of forest biomass for energy is part of a changing forest management paradigm that brings systematic decreases or increases in the amount of carbon stored in forests. If there is a decrease this diminishes the climate benefits of forest bioenergy. If there is an increase the climate benefit is enhanced. The most important way to fight climate change is to transform energy and transport systems as soon as possible so that we can leave fossil carbon in the ground.

Sustainable bioenergy is available now, and is compatible with existing energy infrastructure, enabling immediate substitution of coal, natural gas, or petroleum fuels. Moreover, it can actually remove CO2 from the atmosphere when combined with carbon capture and storage of the CO2 associated with bioenergy use. Bioenergy can therefore play a significant role in supporting energy system transformation to achieve carbon neutrality.

Fresh logging residues piled and covered typically remain at forest roadside storage for a number of months reducing both moisture content in the biomass and nutrient loss from the forest.

In conclusion, IEA Bioenergy TCP notes that the “use of woody biomass to meet growing energy demand as well as its carbon neutrality goals should not be excluded because there may be risks of unsustainable practices. Rather, the focus should be on what practices, innovations, and policy regulations are required to ensure sustainable sourcing and efficient conversion to bioenergy and bioproducts.”

About IEA Bioenergy TCP

The IEA Bioenergy Technology Collaboration Programme (IEA Bioenergy TCP) is a global network on research and implementation of bioenergy, established under the International Energy Agency’s Implementing Agreement mechanism. The IEA Bioenergy TCP comprises a world-wide network of experts in every aspect of the value chain of biomass for energy, who are from the

research community, institutions of higher education, government agencies, and industry. IEA Bioenergy has a rich and excellent history of encouraging and perpetuating the use of biomass as an energy source, to help lessen dependence on fossil fuels, both within and outside its member countries.

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