Emerging commercial sector
Pyrolysis does have costs associated with the machinery and heating (around k273 US$4 per gigajoule) and is dependent on a supply of cheap biomass. At the local or field scale, biochar can usefully enhance existing sequestration approaches. It can be mixed with manures or fertilizers and included in no-tillage k278 methods, without the need for additional equipment. Biochar has been shown to improve the structure and fertility of soils, thereby improving biomass production. Biochar not only enhances the retention and therefore efficiency of fertilizers but k3296 may, by the same mechanism, also decrease fertilizer run-off. For biochar sequestration to work on a much larger scale, an important factor is combining low-temperature pyrolysis with simultaneous capture of the exhaust gases and converting them to energy as heat, electricity, k3919 bibful or hydrogen. Depending on the feeds tock used and bioenergy produced, low-temperature pyrolysis with gas capture (but no sequestrate- tin) can be a carbon-neutral energy source. Most companies that generate bioenergy in this way view biochar merely as a byproduct that can itself be burned to offset fossil-fuel k578 use and reduce costs. But our calculations suggest that emissions reductions can be 12-84% greater if biochar is put back into the soil instead of being burned to offset fossil-fuel use. Biochar sequestration offers the chance to turn bioenergy into a carbon-negative industry.