This week, NRDC released a Fact Sheet entitled Putting U.S. Biochar Policy on the Right Track. The Fact Sheet comes a week ahead of the publication of an NRDC-sponsored scoping study on biochar, and highlights its key findings. Our aim? To give an overview of biochar production technologies, particularly as it relates to the potential environmental concerns associated with biochar production and use, and to make recommendations for a research agenda to support biochar policy development in the U.S.
But first things first. What is biochar?
Biochar is a recently coined term for charcoal that is formed by heating biomass at high temperatures in the absence of oxygen and then added to soil to improve its health. Interest in biochar has peaked in the last few years, largely due to its potential as a tool to mitigate climate change. Research on ancient Amazonian terra preta soils, whose fertility seems to have been increased through the aboriginal practice of adding charcoal to soils, has shown elevated levels of carbon that have been stable for thousands of years. This provides the basis for claims that biochar could play a role in mitigating climate change by sequestering carbon dioxide—that is, absorbing it out of the atmosphere and storing it safely by creating highly stable pools of carbon in soils.
So why is NRDC interested in entering the conversation about biochar?
For a time, biochar seemed to enjoy status as a miracle cure to the global climate challenge. But a lack of commercially operating biochar production systems, which has resulted in a shortage of biochars for actual field trials, means that there remains a great deal of uncertainty about the environmental and economic performance of different biochar production pathways. It also means that estimates of the potential for biochar production and carbon sequestration are highly uncertain and largely premature at this time. In addition, many environmental risks associated with the production and use of biochar must still be addressed before we can responsibly scale up its production and use.
While acknowledging the enormous attractiveness of technologies like biochar that promise to reduce the amount of carbon in the atmosphere, McKibben stressed that work on biochar must be undertaken carefully and with “our eyes as wide open as possible”, taking cautions “at least as seriously as the promise…that has attached itself over the years to [biochar].” He raised questions about “the scale with which [biochar] is being pursued”, compared to what he called “the relative puniness of the scale of the science on which it’s so far based”, and warned against industrializing technologies without adequate analysis to understand their impacts. In the case of biochar, this includes impacts to the ecosystems from which biomass feedstocks would be sourced.
NRDC believes that consideration of biochar’s multifold benefits—its potential to improve soil fertility, protect water quality by improving nutrient uptake, and generate renewable energy—makes a more robust case for developing our understanding of biochar systems than a narrow focus on biochar’s potential to sequester carbon. As the Fact Sheet lays out, we recommend an aggressive, well-coordinated national research and demonstration strategy to mitigate the uncertainties surrounding biochar and ensure that U.S. policy on biochar is environmentally sound. For more in-depth analysis on the promise and risks of biochar, and the path forward for biochar research, stay tuned for the release of our full report next week.