MSU researchers explore AD-to-EV potential

A team of researchers at Michigan State University (MSU) is studying ways to generate renewable energy from dairy farm waste to charge electric vehicles.
Wei Liao, a professor in MSU’s Department of Biosystems and Agricultural Engineering (BAE) and the director of MSU’s Anaerobic Digestion Research and Education Center (ADREC), led a demonstration workshop on 19 July showcasing the novel research linking dairy operations to the auto industry.
Liao was joined by MSU animal science professor Barry Bradford, BAE professor Ajit Srivastava, dairy farm manager Jim Good and BAE research specialist and ADREC manager Sibel Uludag-Demirer.
A Srivastava-designed electric tractor was showcased, as it can operate on renewable electricity generated by a mobile renewable EV charging station, which features an anaerobic digester and external combustion energy.
The majority of the US dairy industry still operates at small- and medium-sized enterprises of fewer than 1,000 cows. Dairy remains Michigan's leading agricultural commodity, accounting for almost 5% of the state's gross domestic product.
Liao said his hope is to implement mobile EV charging units on small- and medium-sized dairy farms as the state continues shifting toward EV production to reduce carbon emissions from petrol-powered vehicles.
He wants to give farmers in rural communities a way not only to charge their own EVs, but also to generate revenue doing it for other’s vehicles.
“We want to use this opportunity to link together the agriculture and auto industry,” Liao said. “They can both benefit from each other.”
Liao also hopes to help encourage the dairy industry make progress on becoming carbon neutral, or reaching net-zero carbon emissions.
He said that currently about 45% of the carbon in animal feed ends up in manure and is partially released as methane – a greenhouse gas (if not collected) — into the atmosphere.
If farmers can use the waste for high-value applications, like producing electricity and charging EVs, he said part of the climate problem becomes part of the solution.
“That’s just a win-win,” Liao said. “We can achieve the carbon neutrality of dairy farms and can similarly reduce emissions for the transportation sector.”
MSU converts food and animal organic waste from campus at its South Campus Anaerobic Digester (SCAD).
The digester, an above-ground steel tank capable of holding 450,000 gallons, has been in operation since 2013 and has digested roughly 60,000 tons of manure.
In 2022, it digested 12,500 tons of manure from the MSU dairy farm and 15,000 tons of food waste from MSU’s cafeterias and the greater Lansing region.
The digester produces about 2.8 million kWh of electricity per year, and 10% of that energy powers the digester itself. The remainder  assists in powering 10 buildings across MSU’s south campus.
The mobile units Liao is working towards installing on small and medium-sized dairy farms won’t be as big and won’t be able to initiate the same amount of power as the SCAD.
He said they will have the capacity to induce 30 kWh of renewable energy per day, or over 10,950 kWh of energy per year.
While that figure won’t be enough power to run an entire farm, Bradford said it could grant farmers different operational opportunities.
For example, the energy from these units could charge batteries of emerging electric skid-steer loaders, or small low-power tractors used to clean animal pens.
“If you could charge (these tractors) yourself without paying a lot and having to deal with how you’re going to charge them, that could potentially be a game changer for how jobs are done on dairy farms,” said Bradford, whose role on the project is to understand how these units will impact dairy farms.
He also said electric charging stations on dairy farms could bring additional economic opportunities. As EVs become more popular and people look for places to charge them, dairy farms could become a viable option that allow visitors to charge their cars while also experiencing the work of local farms.
“Because it takes a little while to charge EVs, longer than it does to fill a tank of gas, farms can keep visitors occupied by selling them a sandwich or an ice cream cone. Maybe they can do a $5 (€4.5) tour of the farm,” Bradford said. “This could be a more mixed funding model where you have agritourism, energy and — of course — milk.”
Funding for the projects comes from MSU AgBioResearch, along with the Michigan Economic Development Corporation, MSU Extension and the U.S. Department of Agriculture’s (USDA) Agriculture Research Service.

Source: Jack Falinski