Biochar sequestration needs a serious look
My Clean Break column today revisits the idea of creating “biochar” out of wood waste using a pyrolysis process, and then blending the char in topsoil as an alternative way of sequestering carbon. We know that, done properly, we can lock about 60 per cent of the biomass’ carbon into the char. We also know the char, when mixed in topsoil, helps with water and nutrient retention. The char is also easy to weigh and package, meaning it’s an ideal substance for calculating carbon offsets as part of carbon-trading efforts. I wrote the column specifically to draw attention to the pine-beetle infestation on the northwest coast and a recent study that said the dead trees — rather than absorbing CO2 — are releasing huge quantities of greenhouse gases as they decay and rot. One solution could be to harvest the dead wood and convert it into biochar. It’s worth a serious look, since carbon capture and sequestration technologies being considered by the oil and coal industries simply can’t be applied outside of specific facilities and locations. With Canada’s emissions growing, not shrinking, we have to consider all approaches.
Tyler Hamilton is senior energy reporter and columnist for the Toronto Star, Canada's largest daily newspaper. In addition to this Clean Break blog, Tyler writes a weekly column of the same name that discusses trends, happenings and innovators in the cleantech market. This blog is a personal project started in April 2005. It is not an official blog of the newspaper. Tyler can be reached at tyler@cleanbreak.ca
April 28th, 2008 at 7:32 pm
A great idea for Toronto’s Norway Maple (tree) infestation. I think right now they are being mulched to sell to landscape contractors. Tim Flannery heralds this process as being carbon-negative. There are a number of video’s about it on the biochar.org website. Thanks for mentioning nutrient retention, as this implies protection of watersheds from runoff and subsequent eutrophication.