A new report by the German National Academy of Sciences Leopoldina (or Deutsche Akademie der Naturforscher Leopoldina; DANL) advises Germany to avoid promoting bioenergy production and to insist that the EU’s 2020 target of 10% renewable energy in transport should be revisited. DANL concludes that, “Germany should not focus on bioenergy to reduce the consumption of fossil fuels and GHG emissions.”
They argue that Germany should stay away from first-generation bioenergy crops, such as wheat or rapeseed, that could affect the country’s food supply, and that Germany has no land to spare for either first-generation feedstocks or second-generation cellulosic crops (such as switchgrass or short-rotation poplar) if it continues to abide by existing environmental regulation. The report states:
“In the view of the authors it seems unlikely that future increases in crop yields will outpace the growth of the world population and of its standard of living.”
Additionally, the report points out that biofuels typically offer little to no greenhouse gas benefit relative to the fossil fuels they replace, due to the energy required for cultivation, fertilizer production, and carbon emissions from indirect land use change (iLUC). The report rules out bioenergy from forestry on the basis of environmental degradation and a carbon debt that would take decades to repay, arguing that:
“There is presently a substantial risk of sacrificing forest integrity and sustainability for maintaining or even increasing energy production without mitigating climate change.”
It dismisses algae because of the low energy return on investment (the authors believe it is generally less than one) achieved by current technologies.
After discounting most commonly considered potential bioenergy feedstocks, the DANL concludes that any future domestically produced bioenergy (which would amount to only a very small fraction of total national energy demand) should come only from animal manure and from agricultural residues. Even in this case, they state, only a tiny fraction of residues can be utilized for bioenergy as most is needed for animal bedding and to plow back into the fields to preserve soil quality; the report notes that:
“At present, European cropland soils are losing too much carbon. For sustainability, it is therefore import that in future more residues are plowed back into the soil.”
In conclusion, the report recommends that,
“Germany should concentrate on other renewable energy sources such as solar heat, photovoltaics, and wind energy, whose area demand, GHG emissions, or other environmental impacts are lower than those of bioenergy.”
Read the full study here.