Reconsidering bioenergy given the urgency of climate protection

Abstract

The use of bioenergy has grown rapidly in recent years, driven by policies partly premised on the belief that bioenergy can contribute to carbon dioxide (CO2) emissions mitigation. However, the experience with bioenergy production and the pressure it places on land, water, biodiversity, and other natural resources has raised questions about its merits. Recent studies offer a lesson: Bioenergy must be evaluated by addressing both the stocks and flows of the carbon cycle. Doing so clarifies that increasing the rate of carbon uptake in the biosphere is a necessary condition for atmospheric benefit, even before considering production-related lifecycle emissions and leakage effects due to land-use change. To maximize the role of the biosphere in mitigation, we must focus on and start with measurably raising rates of net carbon uptake on land—rather than seeking to use biomass for energy. The most ecologically sound, economical, and scalable ways to accomplish that task are by protecting and enhancing natural climate sinks. Rather than prioritizing bioenergy production, researchers and policymakers should pursue carbon management initiatives such as the reforestation project pictured here. Such efforts are much more likely to significantly reduce atmospheric CO2 concentrations in the near and medium term. Image courtesy of Lisa M. Dellwo (photographer). Hence, a major reprioritization of climate-related research, policy, and investment is urgently required, a move away from bioenergy and toward terrestrial carbon management (TCM). Researchers and policymakers must pursue actionable mitigation approaches that have the best chance of significantly reducing atmospheric CO2 concentrations in the near and medium term. When the biosphere is engaged, the emphasis should shift toward large-scale natural climate solutions, including the protection, restoration, and enhancement of forests and other terrestrial carbon sinks. As energy researchers and policy analysts have confronted the global warming problem over the past several decades, industrial-scale … [↵][1]1To whom correspondence should be addressed. Email: DeCicco{at}umich.edu. [1]: #xref-corresp-1-1