Late last year, on November 30, 2016, the European Commission (EC), proposed requiring fuel suppliers to have a 3.6% minimum share of transportation fuels from a preapproved list of non-food feedstocks by 2030. The mandate would come into effect beginning in 2021 and is an important step toward promoting investment security and commercialization of advanced biofuels technologies.
Eligible non-food feedstocks for the 3.6% mandate would include forestry and agriculture residues, among other wastes and byproducts. Some of these feedstocks may offer substantial greenhouse gas (GHG) emission savings compared to fossil fuels, according to the EC’s assessment included in their proposal. And, all of these feedstocks seem like products that would otherwise be left on the field or in the forest. So, if there is an opportunity to reduce waste through advanced biofuels production, we should do it, right?
But wait—it’s not necessarily such a simple question. Shouldn’t we assess the current role of waste and residues before promoting their usage? There are a number of potential environmental issues related to using agriculture and forestry waste and residues, such as straw, bark, branches, leaves, needles, and tree tops as biofuel feedstocks. These residues serve environmental functions when left in the field. They provide cover for the soil that protects it against wind and water erosion. They contribute to building organic carbon in the soil, and they improve soil structure, which enables water filtration and makes it easier for crops to grow. Residues provide food and habitat for organisms in the soil (e.g., roots, bacteria, fungus, worms) that break down residues and roots. Leaving residues in the field returns nutrients (e.g., nitrogen, phosphorus, magnesium) to the soil and reduces the need to apply inorganic fertilizer.
There is evidence, especially for crop residues, that some fraction of residues can be removed from the soil while still leaving enough to provide adequate environmental services. In addition, if farmers apply conservation measures such as planting cover crops and reducing tillage, they could potentially harvest more residues while still practicing sustainable agriculture. We know that residues can be managed sustainably. The question is, how do we know they will be if we incentivize the use of residues for biofuel?
Existing legislation is not sufficient enough to ensure sustainable residue harvesting. For agriculture, the EU Common Agriculture Policy has minimum soil protection conditions for farmers receiving farm subsidies. The member states have implemented these requirements, but in most cases, they do not specifically address residue management, nor do they require soil organic carbon measurement, monitoring, and reporting—and enforcement and compliance is weak. Applying alternative measures may also increase costs, which farmers may not want to bear.
While there is legislation governing soil protection on agricultural land, there is nothing similar for forests. Member states have the prerogative to regulate forest management (except the illegal timber trade as well as birds and habitats). Therefore, as part of its proposed 3.6% biofuel mandate, the EC would introduce sustainability criteria for forestry management governing the use of residues for biofuels feedstocks, with the objective of minimizing the impact on soil quality and biodiversity. But, the requirement in the proposal as it currently stands is too general to ensure that forest managers apply sufficient measures to minimize the impact of residue removal on soil. Nor do the criteria require soil organic carbon monitoring and reporting in forestry.
As the EC proposal makes its way through the process of consideration (which began in 2017 and might last until the end of 2019), the European Council and the European Parliament could introduce additional sustainability criteria to prevent potential environmental risks and secure long-term policy certainty. In particular, suppliers of feedstocks that directly affect soil and biodiversity could be required to have a management plan for agriculture and forestry measures that ensure maintenance of soil cover; protection of soil organic carbon and nutrients; protection of biodiversity; consideration of local conditions, such as slopes and riparian zones; and soil organic carbon monitoring and reporting. If policy makers cannot develop practical and effective criteria to ensure that a given waste or residue is harvested sustainably, then it should be excluded from the list of approved, eligible feedstocks under the 3.6% mandate.
The EC’s proposed mandate can indeed be an important step toward advanced biofuels, but it can and should do more to avoid unintended consequences. Improving the sustainability criteria defined in the mandate will help ensure that it reduces life-cycle GHG emissions without harming the environment in other ways.