NISKAYUNA, New York (Reuters) - Storing power from alternative energy sources in electric car batteries holds promise, but it could be at least 10 years before researchers figure out how to integrate them into the grid, General Electric Co's top research executive said in an interview.

Many energy researchers believe electric car batteries could solve the problem of intermittent power generation from wind turbines and, perhaps, solar power.

The Danish Energy Association, along with Siemens and other companies, is working on a project on the island of Bornholm to store in electric car batteries excess wind power generated when the weather gets blustery. During calm weather the power would be sent from the car back to the grid, a technique termed "vehicle-to-grid."

As the wind power industry grows, worries have increased about the capacity of the power grid to handle the extra, intermittently generated energy. Vehicle-to-grid has garnered interest because some U.S. wind farm capacity has been shut down during gusty times because the grid could not absorb the extra energy.

"I think this is a very cool idea," Mark Little, GE's global research head, said this week at the company's global research headquarters. "I like the potential of it."

But he cautioned it could take 10 years before there are enough electric cars on the road to begin seriously testing the idea.

"I think it is going to be a while coming," he said. "Once we get enough of a population of cars to matter, it's going to take a while to integrate those and figure out where it should be."

Little said storing power in car batteries would most likely happen first in California, where people have typically been early adopters of advanced technology.

GE is working with government and utility partners on building "smart grid" technologies to make power transmission more efficient and reliable. One goal is to allow consumers to see real time pricing of electricity during peak load hours so they can choose to run their power-thirsty appliances during cheaper off-peak hours.

GE researchers said the expanded consumer-to-utility communication powers of a smart grid could tell consumers the cheapest time to charge their plug in electric hybrid cars and the best time to offload vehicle power to the grid.

This week GE announced the "Net Zero Energy Home," which will be available starting in 2015. In the plan, new homes could become nearly energy self-sufficient through energy-sipping appliances, home electricity management devices to work with the smart grid, and alternative power generation sources like small wind generation and solar panels.

Little said electric vehicles should play into the smart grid just like any other big user of power in the home.


- Timothy Gardner