For Peter Bauer, work on electric and hybrid electric vehicles started as a sideline when Notre Dame’s team won the Formula Lightning Electric Race Car Series inaugural race in 1994 in Cleveland.
Bauer, professor of electrical engineering, was co-director, with director Bill Berry, of the program that included undergraduate engineering students—mostly electrical and mechanical—and involved detailed modeling and computer simulations of a car race.
“You could use the computer to optimize the gear ratios, predict and optimize lap times and minimize energy usage,” recalls Bauer, who still teaches a course on electric and hybrid electric vehicles.
“The students learned a lot through this practical exposure to the subject area. You learn so much from the development of electric race cars, and it can often be directly applied to the real world of commercial EVs and HEVs.”
The focus on electric and hybrid electric power generation, and its real-world applications including generators, buildings and other uses as well as cars, accelerated about eight years ago and now accounts for the majority of Bauer’s research, with some work remaining from his earlier interest in digital control and signal processing, as well as swarm technology.
The aim is to generate energy most efficiently and store excess energy for later use in an energy buffer. Therefore power generation and power usage are decoupled from each other, unlike in current conventional vehicles, where the generated power matches the used power at any point in time.
The problem with that, Bauer says, is that most of the time, a vehicle requires much less power than what corresponds to its efficiency sweet spot. For example, a 300-horsepower Corvette would need to generate roughly about 150 HP to operate at its efficiency optimum.
However, in reality it generates a small fraction of this power most of the time, putting the engine into a very inefficient operating regime that often wastes more than 90 percent of the fuel’s energy. “That’s the problem with all cars nowadays,” he says. “Engines rarely run at their optimal operating point.”
Bauer works to buffer the energy in storage devices called ultra-capacitors. Components were prohibitively expensive for commercial use only a few years ago, but costs are trending down. A six-pack of ultra-capacitors that cost more than $600 five years ago now sells for $200.
Three years ago, Bauer and two partners started SlipStream, a company that aims to develop efficient hybrid electric power generation systems with applications such as HEVs and standby generators for military ops and power generation in cold climates where generators run constantly. Current technologies often achieve average efficiencies of less than 10 percent.
Although the principle of SlipStream’s hyper-efficient generator has been demonstrated, the company is still conducting tests for reliability and robustness and is in the process of improving packaging of the entire system.
This summer Bauer starts a yearlong sabbatical in Spain at the Renewable Energy Institute in the Polytechnic University of Valencia, near the Alcoy campus where he taught students in the 2011 Notre Dame Engineering program for six weeks last summer.