IN-DEPTH: Biogas energy in Europe – from great promise to uncertain future

Biogas production in Europe has experienced an upsurge since 2000, reaching 14,9 Mtoe in 2014, as a result of national and EU policies to promote renewable energy sources. In Europe, biogas is principally used to generate electricity, contributing to 6.1% of power generation from renewable sources. First subject to strongly supportive policies, the biogas sector has seen major shifts in policy in recent years that will significantly affect its development and which are likely to deepen with the revised Renewable Energy Directive proposed in November of last year.

Biogas is a mixture of carbon dioxide and methane produced by the anaerobic digestion of biomass. Biomass typically used to produce modern biogas in Europe includes manure, harvest residues, household and industrial organic waste, and energy crops. The plants processing these types of biomass are commonly referred to as “agricultural” or “other biogas” plants to distinguish them from those producing biogas from landfills or sewage sludge. These latter have traditionally been used for waste cleanup and stabilization, with energy production being a happy byproduct. Most of the growth in biogas production in Europe has come from “agricultural” plants which account for 70% of total production. The appeal of biogas as energy source comes from its potential to strengthen domestic energy supply, increase income and employment in rural areas, and reduce GHG emissions relative to fossil fuels.

Since the early 2000s a number of European countries have encouraged  the development of biogas through supportive policies including feed-in-tariffs and green certificates for electricity, public grants and investment subsidies for new plants, and guarantees of origin for biogas upgraded into biomethane. In a number of countries including Germany, Italy, Czech Republic, France, and Austria, such policies were specifically geared to agricultural biogas. They included, for example, premiums for the use of energy crops, manure, green waste, or other agricultural feedstock, and investment subsidies for farms to promote income diversification.

Biogas Plants in European countries in 2013 by type. European Biogas Association (2014), Biogas Report.

This resulted in a rapidly growing but highly policy-sensitive sector. In this context, a policy shift in recent years raises questions about its future development. At the center of the issue lies the controversy on the GHG emission effect of using energy crops for the production of bioenergy. Indeed it is now widely accepted that crop-based bioenergy is not necessarily carbon neutral and may in fact entail higher GHG emissions relative to fossil fuels as a result of cultivation practices and ensuing land use changes. For instance, GHG emissions from the soil are directly related to fertilizer application, but this relationship is difficult to quantify and control as it depends on site-specific conditions. Additionally, land use changes both on the land where the energy crops grow and on other lands cultivated to compensate for the loss in food production affect the GHG balance of crop-based bioenergy. These factors can contribute to a positive GHG balance and even higher emissions than would result from fossil fuel use if, for example, lands with high carbon stocks like forests and grasslands are converted to conventional annual cropland.

Reacting to the prevalent debate on bioenergy sustainability, a number of European countries, including Germany and Italy which together make up 63% of total production, have amended their policies to limit the use of energy crops and especially food crops (e.g. maize) [2. This was accomplished by removing premiums attached to energy crops, and instead introducing premiums for the use of manure and organic wastes of agricultural, industrial, or residential origin. These policy developments are reflected at the EU level in the proposal for the revised Renewable Energy Directive, which extends a reinforced GHG savings requirement of 80% to biogas-based electricity and heat. Additionally, the revised directive lowers the 7% cap on food-based transport fuels to 3.8% by 2030, which affects the biomethane sector.

What these developments make certain is that the biogas sector will not continue expanding the same way it has until now. Just what contribution the sector will make to Europe’s renewable energy targets in the future, however, is still unclear. A factor that is expected to impact the entire bioenergy industry is the development of sustainable production systems for non-food energy crops. For biogas in particular, a more immediate opportunity presents itself in the EU’s move to promote waste recovery and recycling crystallized in the Circular Economy Strategy. Germany, for example, made separate organic waste collection in communities mandatory in 2015, dedicating this waste to its biogas and compost producers. The dissemination of such collection and recovery policies will generate alternative, more environmentally-friendly feedstock for the sector and new growth possibilities.

This article was first published on ICCG’s International Climate Policy Magazine n. 44.

(Image: Biogas installation on a dairy farm in Grosseto, Italy (2016). Photo credit: Delfina Grinspan.)