Matthew Wisniewski / Wisconsin Energy Institute
Under the hood of the converted Ford F150.
A Ford F-150 pickup truck doesn’t exactly scream “tree hugger.” Yet researchers at UW-Madison’s Wisconsin Energy Institute have turned one into a billboard for sustainable and renewable energy.
The Pure Electric Research Vehicle runs on electricity requiring 108 battery cells. It can travel 50 to 60 miles without having to recharge, and it’s logged over 4,000 miles since its conversion from gasoline.
And while the truck is a bit of a showpiece, Thomas Jahns, Grainger Professor of Power Electronics and Electrical Machines at UW-Madison, insists that it is first and foremost a research vehicle.
“It’s not only focusing on batteries by themselves but actually combining them with other types of energy storage components to try to come up with something that’s better than what either one of them is alone,” says Jahns. “It’s the proverbial one plus one adding up to more than two.”
And while Jahns is waiting for the day when a majority of the cars occupying the nation’s roads are electric, the work he and his colleagues are doing in the Johnson Controls Advanced Systems Test Lab goes well beyond electric cars. The lab is one part of the Energy Institute, which provides a forum for energy researchers across campus to more easily interact.
“The future when it comes to electrical systems is on the verge of changing,” Jahns says. “Most of the electricity that we get in this state is generated by coal, and there are a lot of emissions that go along with that. The question is, what replaces it?”
Answering that question, and understanding the best and most efficient ways to store renewable energy, has been the focus of the lab since Johnson Controls donated the state-of-the-art equipment in May 2014.
“Right now you’ve got big power plants on the edge of the city. When we get to the point where there is a photovoltaic array on every rooftop, you’re talking about taking that power plant and breaking it into a million little pieces,” explains Jahns. “That’s a very different system to organize and run compared to having a limited number of really big power plants.”
Distributing renewable energy across a city, while considerably more environmentally friendly, creates new challenges. Coal-generated power is always available. It can be burned day and night, supplying the constant ability for people to flip a switch and be illuminated. With renewable energy sources like solar and wind power, weather can interrupt the energy stream, creating “valleys,” or drops in electricity.
“The sun goes up, the sun goes down, wind blows, wind doesn’t blow, and we expect our lights to go on,” Jahns says. “You have to be creative in terms of how you cope with the fact that you need to fill in those valleys when the sun goes down.”
Batteries are one way to cope with variability, but a basic battery only generates one or two volts of electricity, an amount perfect for a remote control but inadequate for storing the thousands of volts needed to light up a city.
“If you’re starting to talk about using batteries to light up the city of Madison, you’re not just talking about one, two or three batteries, you’re talking about literally thousands of batteries,” Jahns says. “It’s hard for even the optimist to imagine exactly what that would look like.”
But experiments with the Pure Electric Research Vehicle might someday provide clues.