Wood-fired power will actually increase emissions over timescales relevant to the Paris Agreement
Biomass was central to the pioneering Indian environmentalist Anil Agarwal’s thesis on the differing environmental challenges in rich and poor countries. Much of the Third World’s resources were employed to produce biomass for consumption in the West.
But for their own consumption (however low), the poor were more dependent on biomass than the rich, living in what he called a “biomass-based subsistence economy”. Even as the West largely shifted to fossil fuels, biomass still accounted for most of the energy consumption of the poor in developing countries.
But that has long been changing. Designed to meet climate targets, the European Commission’s Renewable Energy Directive (RED, 2009) has fueled a boom in the production of biomass for energy use. This includes liquid biofuels such as bioethanol and biodiesel (blended in traditional fuels), biogas and well as solid biomass such as wood pellets which is burnt for heat and power production.
All told, bio fuels accounted for 8.8 per cent of the EU’s primary energy supply in 2016. Despite the much-heralded boom in wind and solar, all other renewables together only accounted for 4.8 per cent.
Under the RED, biofuels are defined as carbon neutral, based on the reasoning that the carbon dioxide released on combustion will be absorbed by next year’s biofuel crop. However, this does not account for the fact that not all biomass is sustainably sourced and may lead to an increase in emissions from land use change and deforestation, as well as emissions from the growing use of fossil fuels in biomass production.
But this reasoning poses a more fundamental problem for the use of wood as a fuel.
As the European Academies’ Science Advisory Council noted this year, burning forest biomass transmits carbon from the forest stock to the atmosphere within minutes. But there is a time lag between this initial release and the replinshment of forest carbon stocks through regrowth.
This carbon ‘payback period’ may be of the order of years if not centuries. Thus, the concept of carbon neutrality is “both uncertain and highly time- and context-dependent”. A payback periods of decades increase the risk of overshooting Paris Agreement targets.
This advice merely reiterated the appeal of 800 scientists who wrote to the EU Parliament last year. Indeed, these concerns have been known for even longer.
At least since 2017, the UK government has recognised that biomass produced no emission savings, while the country’s Committee on Climate Change has urged the government to provide no further policy support to large-scale biomass without carbon capture and storage (CCS). In a rare admission of the excesses of the Nordic model, Denmark’s Council on Climate Change has noted that the country already consumes more biomass per capita than is likely to be sustainable if “repeated on a global scale”.
Nevertheless, as Playing with Fire, a new report by the London-based think tank Sandbag has emphasised, buoyed by the European demand, a global industrial wood pellet production business has mushroomed overnight, and production has more than doubled since 2010. The EU is the world’s largest market and its imports alone account for nearly a fourth of global production.
The easy conversion of existing coal-fired power plants (which are to be phased out) to burn wood has driven much of this demand for pellets. In the past, most of this growth in biomass consumption in current and former coal-fired plants has taken place in the UK and Germany.
Substantial growth is expected as the coal phase-out slowly picks up across the continent and nearly a quarter of the future capacity is expected to be added in the Netherlands, followed by Germany, Ireland, Finland and Spain. The report estimates that once these plants are built, the continent’s consumption of wood pellets will rise to the current global total production.
Moreover, as no phase-out date has been specified for much of Europe’s coal capacity, these numbers represent merely “just the tip of the iceberg”.
Assuming that all EU biomass is sourced from forests in the US south which is its largest current supplier, Playing with Fire estimates that a whopping 207,000 acres will need to be cut down every year to supply European power plants. This is equal to most of the forests in the Netherlands and about half of Germany’s Black Forest.
The demand will of course be met from forests outside the continent, in the continuing tradition of Europe’s colonial ghost acres.
While there is no requirement under EU law to assess the “payback period” for forest-derived biomass fuels, the report estimates the metric to be at least 40 years. Thus, biomass-based power production would actually lead to a net increase in atmospheric CO2 “over timescales relevant to achieving the goals of the Paris Agreement.”
Moreover, the plants burning these pellets would produce just two per cent of the EU’s gross power production. In comparison, as the report points out, Europe adds as much wind and solar capacity every year.
Playing with Fire recommends that biomass should not be considered a renewable source of energy unless operators can demonstrate that the carbon payback period would be less than 10 years.
Europe has a historic coal problem. Much of the European transition out of coal is a transition into natural gas, another fossil fuel, which now contributes more to the rise in global emissions than coal. To keep old coal plants running, conversion to biofuels is another option being aggressively pursued, and the recently-announced European Green Deal has emphasised the centrality of biomass to a zero-emissions economy.
Like the transition to natural gas, the transition to biomass may well promise to be worse for the climate than coal.