Bus-Sized Batteries May Help Efficiency Of US Grid


US: March 10, 2008


LOS ANGELES - The next time some US utility customers collectively pump up their air conditioners on a sweltering summer day, that power may be coming from a battery the size of a double decker bus.


US utilities are increasingly investing in super-sized batteries and other forms of energy storage to reduce their dependence on slow, dirty backup plants, put off building new substations, and to store power from wind farms and other growing but volatile sources of renewable energy.

"We are going into a state of extreme growth," Ali Nourai, manager of distributed energy resources at American Electric Power Co Inc, said of the market for large-scale energy storage. "We sensed it was coming ... now it's happening."

Columbus, Ohio-based AEP, which delivers electricity to more than 5 million customers in 11 states, installed a one- megawatt (MW) battery in West Virginia nearly two years ago, allowing it to delay construction of a new substation and other infrastructure. Six additional MW of storage will be added this year, and the company plans to have 1,000 MW of storage capacity on its system in the next decade.

In AEP's territory, one megawatt supplies enough power for about 800 homes. Right now, the company is using the technology to help distribute power and delay making more expensive upgrades to its system, such as installing a substation.

Large-format storage devices hold so much promise for utilities because they can be charged overnight, when power is cheap and readily available, and can be tapped during the day when demand outpaces supply. And unlike generators or power plants, storage devices can be accessed almost immediately without emitting harmful greenhouse gases.

"Big generators have a hard time changing speed very quickly," said Bill Capp, chief executive of Beacon Power Corp , which makes flywheels that can store energy and relieve pressure on power grids. "We can do it very fast."

Beacon, which is based in Tyngsboro, Massachusetts, is installing its first flywheel plant in New York state and expects to bring in revenue by the end of the year, Capp said. Under its business model, Beacon will build its own plants and sell the power it stores to utilities when they need it.

Storage will become even more important as wind becomes a greater contributor to the nation's energy supply because power can be stored when the wind is blowing fiercely and then accessed when there is little or no wind at all.

"The more wind power that's deployed, the less predictable or stable the grid becomes," Capp said.

Such systems could help avert what happened last month when Texas was forced to cut service to industrial customers because the wind suddenly stopped blowing.

Last week, Xcel Energy said it would begin testing a one MW battery to store energy from a Minnesota wind farm.


CHEAPER THAN GRID UPGRADE

AEP's aggressive storage target, combined with growing interest from other utilities, could be huge for the handful of small companies, one analyst said.

"It's a tremendous growth opportunity," said Craig Irwin, who follows the energy storage market for Merriman Curhan Ford. "Utilities want to improve efficiency, and they can get that by spending on advanced storage technologies, versus an upgrade to the grid which can be very expensive."

Some batteries also can be moved if, after several years in one spot, a utility decides to replace it with a bigger investment in infrastructure.

Irwin added that more utilities would snap up batteries as the cost of the technology continues to comes down.

According to Altair Nanotechnologies Inc, the cost of one of its batteries is about half that of building a peaker plant, a natural gas-fired facility that is run only when there is high demand. Altair Nanotechnologies recently delivered a $1 million, 2 MW battery system to an AES Corp utility in Indiana, and expects to see more such orders.

"There is strong, strong interest," Bob Goebel, Altair Nanotechnologies' vice president of sales and marketing, said.

AES has a $3 million stake in Altair Nanotechnologies, which is also developing batteries for hybrid vehicles.

Japan's NGK Insulators, which is supplying AEP with its sodium sulfur batteries, is a leader in energy storage because its technology is one of the least expensive, Nourai said. A one MW battery from NGK lasts for about 15 years -- longer than many rival technologies -- and costs about $3 million, he said, or about $3,000 per kilowatt. AEP, however, paid less for the battery it is now running, Nourai said.

By comparison, the cost of a new substation can range from a few hundred dollars to a couple of thousand dollars per kilowatt, an AEP spokeswoman said.

Other players in the industry include ZBB Energy Corp , of Menomonee Falls, Wisconsin, which makes zinc-bromine batteries being used by California utility PG&E Corp, and Canada's VRB Power Systems, which makes vanadium-based batteries.

One risk to the storage makers, however, is the utility industry's push to use plug-in hybrid cars as a source of storage. The idea is that hybrids would charge overnight and allow utilities to draw that power down during the day.

"There are many in the industry who think that's going to change the picture again," AEP's Nourai said, adding that he has even warned NGK about the threat to its business. "It's going to be low cost and it's going to compete with a lot of the battery technology today."

Altair Nanotechnologies' Goebel brushes off that threat, saying there is enough need for energy storage that the two technologies would complement one another. And, after all, Altair Nanotechnologies expects to be making those car batteries as well.

(Editing by Carol Bishopric)


Story by Nichola Groom


REUTERS NEWS SERVICE