The Biochar Moment


Is biochar the world’s most promising solution to climate change? That seems to be the news coming out of a multiyear study published in Nature Communication this week.

From WalesOnline:

A substance invented thousands of years ago by Amazonian Indians could hold the key to defeating man-made global warming, Welsh scientists believe.

Here’s the headline from The New Republic, not usually a supporter of anything that might help the timber industry:

Yes, Biochar Really Might Be That Magical

The gist of the study is that biochar could offset up to 12 percent of the world’s current greenhouse-gas emissions. It does this by “reducing methane production from decaying plant waste, reducing nitrous oxide release from soils, and avoiding carbon dioxide emissions by storing carbon in the soil,” according to the BBC.

Twelve percent is no panacea, but it’s as close to a lifesaver as we get with climate change nowadays. Is it possible that a charcoal formed from the burning of wood waste and other materials could provide, at least in part, environmental salvation?

The answer is maybe.

First the positive:

The vision put forward is of a world where waste is burned, where some of the heat from that burning is used to transform waste to charcoal, and where the charcoal is ploughed into soil, increasing its capacity to support crops and locking up carbon for centuries, possibly millennia.

The waste that can be used includes spare stuff from plants, such as husks and shells and stems, and even sewage and plastics – pretty much anything based on carbon, in principle.

Even sewage and plastics!

What’s proposed would be nothing less than a revolution in the way we handle waste – turning it from waste into fuel, fertiliser and climate saviour with a single blast of the charcoal oven.

Now here’s the rub:

The big question, though, is whether you can grow the plants needed for biochar sustainably. As groups like Biofuels Watch have warned, if farmers start tilling virgin land to grow switchgrass, with the intention of creating biochar, then that could end up releasing additional carbon-dioxide and methane into the air. Alternatively, if biochar crops are grown on existing farmland, then that might encourage farmers elsewhere to hack down forests for space to grow the displaced food crops. This could be like the destructive ethanol craze all over again.

So for the Nature Communications study, the researchers just looked at the world’s supply of crop leftovers: corn leaves and stalks, rice husks, livestock manure, yard trimmings. If virtually all of that biomass was used to make biochar, we could conceivably offset 12 percent of global carbon emissions. Trouble is, it would take a massive shift in production: “Using biochar to reduce greenhouse gas emissions at these levels is an ambitious project that requires significant commitments from the general public and government,” said study co-author Jim Amonette of the Energy Department’s Pacific Northwest Laboratory. “We will need to change the way we value the carbon in biomass.”

Well said. While those of us who care about working forests know about the benefits of biomass, the rest of the world still needs to get the message. The stakes are high, and not just for the timber industry. This is much bigger than us.