LISTEN: Food (waste) is fuel with use of 'living' biogas systems
Amy Robinson: Energy production, food waste, and resource management are all serious environmental and social issues. But what if there was only one solution that could tackle all of these problems? Well, there might be... Today, I’m joined by reporter Teresa Homsi, who has been reporting on “biogas systems.”
Teresa, remind us again, what are biogas systems?
Homsi: Biogas is a type of fuel, and it’s made of gases like methane and CO2. Biogas is released by organic materials, as they decompose, so sewage, manure, and food waste are all sources of biogas. But biogas systems work to capture and extract natural gas, to generate energy.
In my reporting, I focused on anaerobic digesters, which are a type of biogas system. They’re somewhat common on wastewater treatment plants, but they’re not used to their full potential or capacity.
Robinson: Right, farmers could really use these anaerobic digestors...
Homsi: Yep, that’s one of the bigger sectors that could take advantage of biogas systems. Right now, only 8 farms in Michigan have a digester that “eats” animal manure, but the American Biogas Council estimates that number could be 253. I did the math, and that’s about a three-thousand percent increase, so it’s definitely an underutilized, untapped resource.
Robinson: What got you interested in this topic?
Homsi: Well, we’re used to hearing about solar and wind as forms of renewable energy. But biogas is not something I think most people are aware of, and what’s so interesting to me about it, is that biogas is a greenhouse gas. So the prospect of not only capturing those emissions, but also using them as fuel is really exciting. Not to mention, this topic combines energy production with waste management.
Robinson: And when we talk about waste, we have to talk about food waste.
Homsi: Right, so kind of a huge statistic here: 40% of all food produced in the US is thrown away, and that’s at every level of production, pre-consumer and post-consumer.
But food is fuel – in literally so many ways. It physically gives us the energy and building blocks we need to live and grow. Everything else – what we flush down the toilet, throw out of our refrigerators, and the stuff that doesn’t even make it to a grocery store – that is all still fuel. And with biogas systems, there's a place for it to go where it can continue to fuel us by generating our electricity and feeding our crops.
We already power our world with organic matter. We literally dig up and burn rocks that are just fossilized life- very expired food, if you ask me. The difference with biogas systems is that the fuel is a bit fresher, a little more... wet and definitely smellier.
Robinson: Biogas systems, like anaerobic digesters, are described as “living systems.” Why?
Homsi: Anaerobic digesters use microbes to eat organic matter, that we either don’t or can’t eat ourselves. I’m not interested in eating sewage, but these microbes are. And as they’re chowing down, they are the little organisms that actually release methane. Those microbes are archaebacteria – that’s a lifeform that predates all other life … it even pre-dates oxygen.
There’s something poetic to me about the fact that our waste is fuel to bacteria that live on the ocean floor and have been around for nearly 4 billion years. We’re collaborating with an ancient lifeform (that will probably outlive us), but they’re helping us continue to live in the foreseeable future.