A scientist’s opinion: Interview with Dr Jacopo Giuntoli on burning wood as renewable energy

Interview with Dr Jacopo Giuntoli, sustainability scientist, life cycle assessment expert and EU bioeconomy researcher, that is collaborating with the Joint Research Centre of the European Commission.


Several Joint Research Centre (JRC) researchers, along with scientists from the European Environment Agency’s Scientific Committee, have stated that burning wood would have a larger impact on the environment than burning fossil fuels. With this in mind, why do you think that the EU institutions promoted the idea of using wood as a form of renewable energy in 2009, even though they were most likely aware of the potential dangers?

Jacopo GiuntoliThe idea of a ‘carbon debt’ associated with increasing the use of forest biomass was first raised in the 1990s, but the scientific debate really picked up after 2009-2010. Since then, several key documents have been published highlighting the issue of long carbon payback times associated with forest bioenergy. These issues were thoroughly investigated while drafting the second Renewable Energy Directive (RED II) and are described in great details in the impact assessment accompanying the REDII. Thus, as highlighted in the JRC bioenergy report, the carbon impacts of forest bioenergy were raised and thoroughly assessed during the political discussions that led to the creation of the REDII.


What alternative means of energy production would you deem climate-friendly?

A key issue with the ‘bioenergy debate’ is that the discussion is, in my opinion, ill-framed. The debate is gridlocked around trying to answer the following question: Does forest bioenergy contribute to climate change mitigation? However, I would argue that we should unpack this question and completely reframe the problem that we are trying to solve. The main postulate that drives the current problem framing is that bioenergy is needed to achieve climate change mitigation targets. This is accepted as true, but, in my opinion, the key to move the debate forward is actually to question this fundamental assumption.

Where does this bioenergy dogma really come from? Bioenergy is considered to be necessary to reach the EU’s climate and energy targets, mainly because the results of modelling exercises using Integrated Assessment Models (IAMs), such as the ones by the Intergovernmental Panel on Climate Change (IPCC), the European Commission, and by the International Energy Agency, include a high share of bioenergy in their decarbonisation scenarios.

However, these results can be questioned on several grounds. For instance:

  • Do the IAMs properly capture all the interactions between bioenergy and the climate (or, crucially, biodiversity)? According to a recent paper (Calvin et al. (2021)), IAMs are indeed limited in the impacts they capture.

  • Do the IAMs, including the IPCC shared socioeconomic pathways, represent the entirety of the solution space? According to a recent study by Otero et al. (2020), they definitely do not, since most models do not explore any scenarios with significant demand-side changes.

  • Most IAMs forecast the contribution of forest bioenergy, principally within bioenergy with carbon capture and storage installations, on the basis that it is a form of negative emission technology. However, if that is the role expected of bioenergy, should such a clause not be explicitly included in energy legislations, stipulating, for example, that subsidies for bioenergy power stations will only be granted if they employ carbon capture and storage?

  • Can climate targets be achieved without increasing the use of forest bioenergy? According to research conducted by the European Commission’s Directorate-General for Energy, it is possible to design scenarios which limit or fully constrain any increase in bioenergy use. Other studies have investigated placing restrictions on the amount of bioenergy consumed by the models and the subsequent impacts (e.g. Fuss et al., 2018).

  • Finally, and this could even be the only point in this list: the climate and biodiversity crises are interconnected and should be tackled together. The latest collaborative report by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services and the IPCC addresses this aspect in a similar way to the JRC report. In my latest paper, I argue that there are alternatives to bioenergy as a mitigation strategy, there is no alternative to healthy forest ecosystems. Therefore, achieving climate targets at the expense of biodiversity and ecosystem health should not be considered a sustainable way forward.


Does using forest bioenergy mitigate climate change?

As I explain earlier, I think this question is ill-framed. Conclusions on the specific extent and role of wood-based energy in climate change mitigation differ widely in scientific literature, ranging from studies concluding that forest bioenergy increases greenhouse gas emissions compared to fossil fuels over a timescale of decades, centuries, or even indefinitely, to others concluding that significant emission reductions can be achieved within reasonably short time frames. This divergence cannot be solely attributed to the use of a specific type of forest biomass – e.g. logging residue from roundwood – but rather to different assumptions based on counterfactuals, to market-mediated effects, and to forest management practices. We tried to clarify some of these issues a couple of years ago.

However, when the biodiversity lens is also applied to the analysis, and once we accept that bio-perversities are to be avoided, we can find clearer answers because we can identify win-win options, which should be the only ones promoted.

In this regard, our latest analysis already provides very clear answers on certain pathways, especially the ones in which biomass for bioenergy is supplied through the conversion of semi-natural forests into plantations. Depending on how the time frame for the conversion is defined, many of the wood pellets from the southern United States, for instance, might fall into this category.


Does the amended RED II promote win-win options and exclude lose-lose ones?

Firstly, we must remember that the European Green Deal does not only include the amended RED II, but it includes many other relevant documents, such as the EU forest strategy, the EU biodiversity strategy, and the EU Land Use, Land-Use Change and Forestry (LULUCF) Regulation.

We found that most, but not all, of the lose-lose options that we assessed are excluded from the European Green Deal, especially those concerning biomass from plantations established in semi-natural forests.

Additionally, our analysis did not cover all possible lose-lose options and the JRC report highlighted potential issues stemming from mismatched incentives across energy legislation: the EU Emissions Trading System (EU ETS) and RED II, and LULUCF legislation.

The first challenge is that, within the EU, different signals are sent to economic operators and to national governments. On the one hand, through zero-rating accounting and by considering forest biomass as renewable, the EU ETS and RED II in principle incentivise economic operators to increase their use of forest bioenergy, thus stimulating demand for wood to produce energy. Additionally, by allowing forest bioenergy to contribute to the renewable energy targets and to be subsidised through national support schemes, RED II permits countries to support forest bioenergy as a way of meeting their targets. On the other hand, by determining the level beyond which any additional domestic harvest (including for bioenergy) will be ‘fully paid’ in terms of carbon (i.e. the Forest Reference Level), the LULUCF accounting in principle disincentivises countries to harvest beyond this limit, unless this is compensated by extra forest growth or unless the positive impact of using this extra harvest (i.e. reducing greenhouse gas emissions in other sectors) makes up for its carbon ‘price’.

Imported forest bioenergy poses a further challenge. RED II largely relies on the fulfilment of the nationally determined contributions (NDCs) under the Paris Agreement. If a country has an NDC that includes LULUCF, importing forest biomass for energy purposes is allowed, because the associated climate impact will be reflected in the exporting country’s climate accounts. This treatment of forest biomass is no different from the treatment of any other imported goods associated with emissions in the exporting country. For LULUCF, it can be argued that not all NDCs express similar levels of ambition on forests under the Paris Agreement, nor the same level of monitoring quality. The potential externalisation of the demand for biomass in the EU (i.e. from countries such as the US and Canada) could lead to leakage of the carbon accounting from EU energy production.

Whether any of the challenges above might result in a negative impact on forest ecosystems will eventually depend on the economic and regulatory framework that each Member State will put in place. In my opinion, two aspects are key: a strong coordination at MS level between different ministries, and the definition of holistic bioeconomy policies. These two approaches are key to devise strategic climate and energy plans which avoid both a sectorial leakage of the carbon emissions from bioenergy (from the energy to the LULUCF accounting sectors) as well as a geographic leakage through large-scale externalisation of impacts due to imports of woody biomass (i.e. wood pellets).

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