On the surface, biofuels seem like the perfect solution to our oil and gas addiction. Make the same kind of fuel from plants and make cars that can run on it. Simple right? Well, as EarthTechling writer Mat McDermott explains, it’s actually much more complex. The luster has long disappeared from first generation biofuels (like biodiesel, ethanol) as we discover that calling biofuels green requires a lot more than plants.
Now that most have realized food stock-based biofuels aren’t the answer, the search continues for other biomass that could accurately bear the mantle of a petroleum substitute. New research shows that biochar may be key to producing just such an alternative.
Soils are among the biggest sources of UK emissions (surprising huh?). A team of scientists from that country’s Natural Environment Research Council (NERC) published a study that suggests applying biochar before planting biodfuel crops could cut soil greenhouse-gas emissions by around a third.
In an attempt to meet the EU’s target of a fifth of energy coming from renewable sources by 2020, the UK have been cultivating crops like miscanthus and coppiced willow for the production of non-food biofuels. Now it appears that by adding biochar as a soil treatment, cultivators could further reduce emissions associated with such production, and even increase the soil’s natural carbon storage capacity.
To test their theory, researchers monitored a plantation of miscanthus for two years. The plots treated with biochar emitted 37 percent less greenhouse gases than those that hadn’t, while in the lab the impact was even bigger at 55 percent.
“We’ve shown that adding biochar suppresses CO2 emissions very significantly over several years,” says Sean Case, a PhD student at NERC’s Centre for Ecology & Hydrology (CEH) and lead author of the paper. “Previous studies have found this effect in the lab and over short periods, but this is the first time anyone has looked at bioenergy crops in the field, and at the effects of biochar over a long period.”
Using biochar in this way could also help close the biofuel loop, as waste fron biomass burned for energy could be returned to help bolster future crops.