Short Wave - Food Waste + Poop = Electricity

Episode Date: January 7, 2020

Some dairy farmers in Massachusetts are using food waste and manure to create renewable energy. Each farm produces enough to power about 1,500 homes. Not only does this process create electricity, NPR Science Correspondent Allison Aubrey tells us it also prevents the release of methane, a greenhouse gas. Follow Short Wave's Emily Kwong on Twitter @emilykwong1234. Email the show at [e-mail] pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Hey everybody, Emily Kwong here, filling in for Maddie who's out training for a thumb war competition. Today, our story comes from NPR correspondent Alison Opry. Hey there, Emily. Hey, Allison, so what you got for us? Well, why don't we start with a pop quiz? What do you say? I thrive in quiz pressure.

Go on. Do you know how much of the food supply in the U.S. never makes it to our mouths? 10%? 30 to 40%? 30 to 40%. That is the estimate. In fact, folks at the USDA, the U.S. Department of Agriculture, estimate that you could fill the Willis Tower in Chicago big skyscraper every year 44 times with the amount of food that goes to waste. That is staggering. You know, food waste is this huge problem. And on top of being a massive waste, when food ends up in a landfill, it rots and a lot of methane is released. And methane is a greenhouse gas, which is a huge contributor to climate change. Right, it traps heat in the atmosphere, and methane is over 20 times more potent than carbon dioxide in terms of its warming impact. In fact, a recent report from the United Nations found that up to 10% of all human-made greenhouse gas emissions are actually linked to food waste.

Humans were just the worst, you know? But we're also kind of good at coming up with solutions. Please redeem our species for us. Okay, sure. Well, to solve this problem, some farmers in Massachusetts are taking all of that methane-making food waste and turning it into energy, actually making electricity to power nearly 1,500 homes. Wow, that's pretty amazing. And to make that energy, these farmers are combining that food waste with something else that can be a big source of methane, especially on big farms. I'll give you a hint, it stinks.

Oh, cow poop. That's right. And it's stored in these big pits. And cow poop can release a lot of methane as well. So you're saying that farmers have found a way to take two methane sources, food waste and manure, and turn it into energy. That's right. Two methane sources, one stone. So today on the show, we head to Massachusetts to get a closer look at how some dairy farmers are turning tons of cow poop and truckloads of food waste into green energy. Allison, I suspect this is going to get messy.

Well, stinky more like it. To borrow a line from our colleague, Dan Charles, we're going to get a whiff of the future. Okay, Alison, before we get into how these farmers are doing this, let's talk about why. Is it just about methane in the environment? Well, I mean, I am sure a lot of farmers do care about the environment, but really, times are tough for dairy farmers out there. I mean, many farmers are looking for ways to diversify their incomes. They've gotten very efficient at doing what they do, producing milk, perhaps too efficient, and that makes it tough to be in business. So my name is Peter Melnick, and I'm a fourth generation dairy farmer in Deerfield, Massachusetts.

I visited Peter's farm late last year. He's one of a handful of farmers in Massachusetts, converting wasted food and manure into electricity. He has essentially turned part of his family farm into this mini power plant. Wow. And he says they're saving about $100,000 a year by producing energy. $100,000 a year. That's a huge save. Yeah. Okay. So how does this waste to energy process actually work? So a key piece of equipment on the Melnick Farm is this anaerobic digester. Fun name. What is an anaerobic digester? So it's basically a big sealed tank and when the food waste and the manure are put into the tank and heated. All of this biomass is broken down by the little micro organisms, the bacteria, and a methane biogas is produced.

From this big mixture. That's right. And the digest. The gester that he has on his farm has a tank that can hold about a million gallons. Of what is basically a big organic waste brownie. Yes, and then as methane is released, it rises to the top of a bubble-shaped dome. We capture the gas in that bubble, and then we suck it into a generator. It's about the size of your car, and that engine runs on methane instead of diesel or gasoline. And that, in turn, is turning a big generator, which is then creating one megawatt of electricity. Is one megawawat a lot of electricity? Well, to put this in context, this operation powers not

only his farm and his home, but a lot more. We only use about 10% of what we make, and the rest gets fed onto the grid, and it's almost enough to do 1,500 homes. That is a huge output of energy, 1,500 homes. And you mentioned that Peter is mixing food waste in with the manure. Why is he adding food waste to? Well, the more you add to the digester, the more involved. volume you have, the more electricity you can make so that manure may not produce enough to make the economics of the digester system work out. You need scale. Right. So Peter's not only using this manure. He's also processing millions of pounds of food waste from across the Boston area, food that is spoiled or surplus, also a lot of waste products from food production facilities around the state.

Traditionally, all this would end up in a landfill, but instead it is trucked to his farm. We presently take in about a hundred ton, which is about three tractor trailer loads every day. Whoa, that is a huge amount of food waste. I watched it. It's amazing. I mean, these trucks come in and it's just piped into this big pit where it then ends up in the digester. He gets waste from the local creamery, waste from a local brewery, a local juice plant. And then another big source for him is waste from whole foods, the grocery chain. 17 of their stores in Massachusetts participate.

There's a woman at Whole Foods, Karen Francheck. She showed us how it all works. We do have items that we can't sell either because they're spoiled, items that are bruised that we might not be able to sell. So what she showed us when we visit it is this big industrial masher. This was at the Whole Foods and Shrewsbury, Massachusetts. It basically gobbles up everything that would be wasted. And you can imagine there's everything

from bones, we put whole fish in there, vegetables. You can have dry items like rice or grains. So it really becomes kind of a liquefied food waste. Liquefied food waste. I know. Okay. And what happens next? Well, so this slurry is loaded into the tank of a truck. It heads to Peters Farm and then it goes right into the digester. Anything that ends up going to landfill or incineration costs us more money.

That is the most expensive way to get rid of waste in our stores. So this is cheaper for Whole Foods, too? That's right, it is. And also, I should point out, in Massachusetts, grocery stores and food producers aren't allowed to send this organic waste to landfills anymore. The state passed a law back in 2014 that restricts this. It applies to all businesses that generate over a ton of organic waste a week. Wow.

So there's an incentive for supermarkets like Whole Foods to participate in something like this. Exactly. Okay, let's go back to our farm for a minute. Can any farmer get in on this? Like, how did Peter get his digester? Well, here's how it works. The digesters are built and run by a company called Vanguard Renewables. Vanguard pays farmers a fee for the use of their land and also gives them free electricity to power their farms and houses.

Right now, there are five digesters spread out across the state. The CEO of Vanguard Renewables, John Hanselman, says he hopes that this whole operation expands. There's more than enough food waste in Massachusetts to feed all of our five digesters, plus many more. Alison, do you get the sense that this is something that can be realistically expanded? You know, I think it really depends on the right mix of policies and incentives. That's what Massachusetts put in place. They passed the commercial food material disposal ban. They had a series of grants.

I mean, this is a new approach. So I think we'd have to look to see would we have some kind of federal policy or other state policies to promote this? Hanselman told me he's really inspired by what's happened in Europe where he says there's more than 17,000 digesters. So we saw what was happening in Europe where anaerobic digestion is extremely widespread. Across the United States, we don't have that incentive program. We don't have the federal energy policy or any federal benefits for anaerobic digestion. We are at the cusp. We are at the early days.

We've finally got the economics to work. And when I spoke to Peter Melnick about this, the farmer, he says he really agreed. As the price of milk has really been flat, the digester has just been a home run for us in that sense. It's made us more sustainable environmentally, but also economically as well. Alison, thank you so much for taking us to Massachusetts where this kind of amazing chain of suppliers and energy makers exists. Now I know where to send all my extra cow manure and food waste. Oh, my pleasure. It was really a great story to report. This episode was produced by Britt Hansen and edited by VLA.

Thanks for listening to Shortwave from NPR.