NEW YORK - One problem perhaps more than any other has proven a drag on the long-term prospects for wind power: how do you turn on the lights when the wind isn't blowing?

A New Jersey company said Tuesday it has joined with Michael Nakhamkin, one of the top thinkers in energy storage, to develop new ways to trap wind-generated power in underground reservoirs.

Nakhamkin has helped develop technology that pulls excess energy off the power grid - usually at night - to run compressors that pump air into sealed, underground caverns that previously held oil, salt or natural gas.

When the grid needs power, air is released and heated to run air expansion turbines. The heating process uses about 100 megawatts of power from natural gas and 200 megawatts of power from the compressed air.

The announcement comes just as a drilling boom for natural gas heats up nationwide. Natural gas can now be reached with new technology has supporters in both the private sector and in Washington because it releases fewer of the greenhouse gases that can lead to global warming and because it has been found domestically in massive quantities.

In urban areas where underground storage isn't feasible, or where bedrock makes drilling a hole expensive, ground-level pipes can be used to store the air, though the capacity is diminished.

"We believe this technology is an important component of a broad effort to combat climate change, an effort that must include increased conservation, expanded renewable energy and new, clean central power," said Stephen Byrd, president of PSEG Energy Holdings, which has formed Energy Storage and Power LLC with Nakhamkin.