Actually, We CAN Put It Back in the Ground

One of the most demoralizing things about climate change is that it’s generally a one-way process: it’s easy for us to put more greenhouse gases into the atmosphere, but not so much for us to take them back out–at least, that’s what I thought until recently.

True, there has been some research into carbon sequestration (putting carbon dioxide directly into underground spaces or at the bottom of the sea), but these processes aren’t very far advanced or very affordable, and some of the plan for them is just to capture CO2 being produced by fossil fuel plants and sequester that. The fossil fuel industry likes to hold this very theoretical idea out as though it’s an available technology, so as to get a free pass to burn more fossil fuels.

But I mentioned that there was some hope, and there is: biochar.

What is biochar? It’s basically charcoal, an extremely carbon-rich material made at high temperatures, from 200 to 700 degrees Fahrenheit, which consumes pretty much everything in the fuel except the carbon. Biochar can be made from practically any burnable material–wood, seed pods, husks, brush, paper, manure, etc.–even trash.

biochar pellets

What’s so great about that? A few things, actually! First, using the right process to make it, biochar produces energy without producing much in the way of greenhouse gas emissions. Second, the process that makes biochar can alternatively make liquid fuels from renewable sources. Third, and most intriguingly, biochar is very stable: you can bury it in the ground, and the carbon won’t go anywhere for hundreds to thousands of years. Fourth, when you do bury it in the ground, it increases the fertility of the soil by making necessary chemicals more available to plants and by helping retain and regulate water in the soil. Fifth, the process is simple enough that it can be used for everything from massive plants to cookstoves.

So the cycle can go something like this: plants grow, absorbing and using carbon from the atmosphere. The plants are harvested, and some or all of the resulting plant matter is made into biochar, producing up to about six times as much energy as it consumes in the process. The biochar is then buried in the ground, accelerating plant growth. Even without this acceleration, the new plants that grow where the old ones were harvested absorb more carbon from the atmosphere, and the process continues.

If we’re willing to commission a lot of large biochar plants and to make biochar a standard part of preparing agricultural lands–including reclaiming currently unproductive lands, such as former farmland that is tapped out or turning to desert–then we can actually pull a huge amount of the carbon dioxide we’ve generated over the past couple of centuries back out of the atmosphere, and reverse the process we’ve been causing that is currently wrecking our climate with no relief in sight.

Photo by Lou Gold

We’re Eating Oil–Literally


I came across a disturbing statistic today: ten to one. This was in Bill McKibben’s book Eaarth: Making a Life on a Tough New Planet:

It takes the equivalent of four hundred gallons of oil annually to feed an American, and that’s before packaging, refrigeration, and cooking. In 1940, our food system produced 2.3 calories of food energy for every calorie of fossil fuel it consumed. Now, says Michael Pollan, “it takes ten calories of fossil energy to produce a single calorie of modern supermarket food. Put another way, when we eat from the industrial food system, we are eating oil and spewing greenhouse gases.”

I think I had actually read this once before and been disturbed by it then, but at the time I was still in blissful ignorance of how fast and how hard climate change would be coming down on us. Reading it this time was painful–but it also made clear an enormous opportunity. Look at this information from a 2009 sustainability report from NYU:

A 2002 study from the John Hopkins Bloomberg School of Public Health estimated that, using our current system, three calories of energy were needed to create one calorie of edible food. And that was on average. Some foods take far more, for instance grain-fed beef, which requires thirty-five calories for every calorie of beef produced. What’s more, the John Hopkins study didn’t include the energy used in processing and transporting food. Studies that do estimate that it takes an average of 7 to 10 calories of input energy to produce one calorie of food.

So that’s painfully depressing. It’s at least possible to imagine not driving a car everywhere and turning off extra lights, but how exactly do we survive without eating?

Fortunately, as I said, there’s a huge opportunity there–three, actually.

  1. Because most food production energy goes into transportation and packaging, eating local, minimally-packaged foods drastically reduces their negative environmental impact.
  2. The figures above are for mainly conventional farming methods. Sustainable methods have a much lower impact.
  3. Eating lower on the food chain (less red meat, more beans and veggies, etc.) also greatly reduces environmental impact.

I’m ridiculously relieved that there’s at least something I can do about this. We’re already following some of these practices, but it looks like this will be the first area of changes for our family, tentatively: going localvore, reducing packaging, and eating low on the food chain. We were going in the right direction, but we need to step our efforts way up. We can do that. Actually, practically everybody could do that. I wish everybody would–but I’d better start with myself.

Photo by C Jill Reed