Every year our family visits the PNE, which is the big annual fair here in the Vancouver area. While we wandered around the exhibits, I came across one that caught my eye, for Cowpower. It’s a project that takes manure and other agricultural waste and turns it into electricity. As you may recall, my One Green Thing for September is converting a portion of my natural gas use into renewable natural gas. This seemed to be in the same vein, and was intrigued. I sent an email to the company asking if there was someone I could speak with. I ended up connecting with Matt Dickson, the founder.
“Cowpower was launched at the end of January at this year,” Matt explained. “I’ve had the idea for several years, and just kind of needed the right time and the right funding to develop and launch it.” He’s partnered with a local farm (the EcoDairy I visited a couple of years ago), which has an anaerobic digester. The digester takes the waste and, using microorganisms, breaks it down into methane and digestate. The methane is used for power. The digestate is handled to separate the liquids and the solids. The solid is a fluffy, fibrous material that farmers use for the cow’s bedding. The liquid is a high-quality fertilizer.Matt outlined what makes the fertilizer so great. “One of the major benefits around anaerobic digestion is most dairy farmers spread raw manure on the fields. The nutrients in the raw manure are in these long chain molecules. The plants have to first break down those long chains before they can absorb the nutrients. When the manure’s gone through a digester those long chain molecules have already been broken down. When you put it onto the field crops find it much easier to absorb the nutrients. The nutrients sit on the land for a much shorter period of time. If you were to spread raw manure and the next day it were to rain heavily, all those nutrients could end up in rivers, streams, lakes. When you spread the liquid fertilizer on the field, even if it rains the next day, all those nutrients have already been absorbed. It’s much, much less impactful to water bodies.”
One of the things I saw at the EcoDairy is that the cows are all kept indoors. I asked Matt if this would work as well if cows were out grazing in the fields, and he said it would not. However, he cited a study from UBC that found that most cows prefer to be indoors. He says that even when farmers allow their cows outside, most of the time at least 80% of the manure ends up in the barn, where it can be collected. Organic farms are the exception. To be certified organic, cows must spend a minimum amount of time outdoors. Those farms would likely not be suitable candidates for the Cowpower program. The best farms will be larger farms, with 200 cows and up, producing conventional milk. Matt says that there are about 50 and 100 dairy farms locally that could build a digester in the next 10 years, with the right incentives.
One of my biggest questions for Matt was why they were using the methane they were harvesting to generate electricity, rather than heat. Since I had recently looked into using renewable natural gas for my home, it seemed like that would be the more efficient way to go. What Matt explained to me is that Cowpower is meant to work alongside the program from my gas company. It turns out that in order to feed natural gas into the system, you need to be located close to the pipeline. And not just close to the pipeline – you need to be upstream. You can be right on top of the pipeline, but if you’re at the end, you’re not going to be able to feed gas in, since it only flows one direction. Electricity, on the other hand, can be fed into the grid far more easily from any location.
The last thing that I really wanted to find out was how Cowpower compares to hydroelectricity. The vast majority of electricity here in British Columbia comes from hydroelectricity. It’s a carbon-neutral, sustainable form of energy generation. Given that we have so much water to generate clean energy, why would we turn to Cowpower, which is fairly expensive to develop? Matt explained that Cowpower is actually carbon negative.“When you build an anaerobic digester you get greenhouse gas reductions in two places. First of all you’re producing a carbon neutral energy source, which goes onto the grid. On the front end, imagine a dairy farm currently. It scrapes the manure into a pit, and that manure is applied to the field a few times a year. While it is in that pit it is producing methane, and that methane is getting released into the atmosphere. When you build a digester, you capture all that methane, and then when you burn it you convert the methane to carbon dioxide.” Since methane is more than 20 times more impactful as a greenhouse gas than carbon, you’re significantly reducing the greenhouse gas emissions from the farm. And that carbon dioxide is considered neutral, because it comes from the plants the cows eat, which extract carbon dioxide from the air.
The other big upside to using an anaerobic digester is odour reduction. I grew up in farm country, and I am all too familiar with the smell when farmers spread manure on their fields as fertilizers. That odour is nearly completely removed during the digestion process. Matt quoted a farmer from Vermont, who said, “Since I installed a digester, my neighbours wave at me with all five fingers.” That would definitely make breathing much more pleasant. By putting a price on the benefits like cleaner waterways, odour reduction, nutrient management and carbon offsets, as well as energy production, Matt is hoping to make anaerobic digesters more affordable to farmers.
After speaking with Matt, I’m sold on the benefits of Cowpower. I haven’t signed on myself yet, just because it’s quite a lot more expensive than renewable natural gas from my gas company. However, I’m definitely considering it, and I’ll be keeping an eye on my monthly budget to see if I can swing it.
I wonder what you think – would you be willing to pay a premium on your electricity bill to support a program like this? And do you think this is the type of thing that governments and energy companies should be investing in? I’d love to hear your thoughts!