Researcher to test new flow battery

Submitted by Marmian Grimes
Phone: (907) 474-7902
07/28/06

University of Alaska Fairbanks Institute of Northern Engineering researcher Dennis Witmer is getting a new toy--one that shows promise for reducing power costs in rural Alaska.

Witmer, who heads the Arctic Energy Technology Development Laboratory at UAF, is best known for his work on fuel cells. Next month, he’s slated to begin testing on a new type of battery that could make alternative energy sources like wind generators and solar panels more viable and cost-effective.

The five-kilowatt flow battery, created by VRB Power Systems Inc. of Vancouver, British Columbia, is scheduled to arrive at UAF next week. Representatives from the company, along with staff at the Arctic Energy Technology Development Laboratory, will set up the test site at the laboratory on the UAF campus.

"We are very pleased that the University of Alaska Fairbanks is undertaking testing of our flow battery technology,"? said Vince Sorace, president of VRB Power Systems. "We believe that our products will enable the installation of significant amounts of wind power and other renewables in many communities and sites across Alaska, thereby significantly reducing diesel costs and diesel emissions."?

Once the flow battery is installed, Witmer plans to run tests for several years, evaluating its performance, durability and reliability in a lab, an unheated warehouse and outdoors.

"It’s really important that somebody take a look at this and make sure it really works,"? he said. "I think of it less in terms of research and more in terms of service to the state."?

The flow battery is about the size of two large bookcases. It’s different from common batteries in that it stores electrical energy in a solution of sulfuric acid and vanadium ions, Witmer said. Traditional batteries, such as those found in automobiles, use solid lead plates in acid to store energy, he said, and can be expensive because they have a relatively short lifespan.

"You can trash a lead acid battery in a day or two if you really work at it, by repeating deep-discharge cycles"? Witmer said. "What we have been told about this battery is it’s much more stable over many more deep-discharge cycles. This extended life reduces the cost of storing energy."?

The reason for that is the flow battery’s liquid storage medium. In a traditional battery, he said, the chemical reaction between the lead and acid can cause degradation on the surface of the lead, which eventually shorts the battery and renders it useless.

"In this vanadium battery, the energy is all stored in liquids,"? he said. "This means there are no active solid surfaces to degrade. In addition, the active substance is vanadium on both sides of the battery, so there is no chemical cross contamination, which has been a problem in other liquid battery systems."?

Batteries are important to alternative energy generation systems for two reasons. Renewable resources, such as wind or solar energy, are intermittent and not always available when needed. Batteries allow excess energy to be stored when it’s available and used later. They also serve as an additional source of energy in times of peak power use. But Witmer said conventional batteries end up being more expensive than burning fuel because their short lifespan ups capital costs.

"People are hoping this is a battery that will work for load leveling with wind power,"? he said. "There are many Alaskan communities that could benefit from this, especially with diesel fuel prices at five dollars a gallon or more in some villages."?

Flow batteries were actually invented in New Zealand in the 1980s, Witmer said. Earlier versions of the battery were quite expensive.

"As time goes by people try to make them more cost-effective,"? he said. "The strategy of this new company is to use inexpensive, commercially available materials and to get costs down to where this technology is cost-effective."?

Note to editors: Representatives from UAF and VRB Power Systems will be installing the battery and available for interviews throughout the day Aug.2.

CONTACT: Marmian Grimes, UAF public information officer, at (907) 474-7902 or via e-mail at marmian.grimes@uaf.edu. Dennis Witmer, Arctic Energy Technology Development Laboratory director, at (907) 590-2836 or via e-mail at ffdew@uaf.edu. Tom Johnson or Jack Schmidt, Arctic Energy Development Laboratory, at (907) 474-1930. Simon Clarke, VRB Power Systems Inc., at (604) 697-8820.