Leveraging smart grid, California delivers power on demand from blocks of ice

Southern California will soon leverage the smart grid to shift on-peak electrical consumption to off-peak periods by delivering power stored in blocks of ice.

The Southern California Public Power Authority has partnered with energy storage provider Ice Energy to roll out the nation's first cost-effective, utility-scale distributed energy storage project.

The 53 megawatt project will permanently reduce California’s peak electrical demand by shifting as much as 64 gigawatt hours of on-peak electrical consumption to off-peak periods every year.

That helps reduce exposure to costly peak power and improves the reliability of the electrical grid.

"Ice Energy's solution is a convenient and cost-effective solution for managing peak demand, and aligns perfectly with our Smart Grid initiatives - enabling our member utilities to deliver reliable, competitively priced electric service to their customers in a sustainable, environmentally-sensitive manner,” said Bill Carnahan, Executive Director of SCPPA, in a statement. “By using storage to change how – and more importantly when – energy is consumed by air conditioning, we can offset enough peak demand in the region to serve the equivalent of 10,000 homes."

So how does it work, you ask? According to an article in Miller-McCune, Windsor, Colo.-based Ice Energy will use its Ice Bear energy storage technology, which freezes hundreds of gallons of water each night when demand for power (and corresponding price) is lower.

Individual Ice Bear units are distributed in 1,500 rooftop and commercial air conditioners across the authority's 2 million customers. When air conditioners are turned in the area on a hot day -- a major draw on California's power grid, as you can imagine -- Ice Bear switches off air conditioning and circulates warm air from the building's interior across panels chilled by melting ice.

The result? Cool air, which goes right back into the building.

It takes about six hours to deplete the ice block, which functions much like a battery. Once it's gone, the air conditioning system switches back on like normal.

Ice Energy claims an 8 percent efficiency advantage for the customer, according to the article.

"SCPPA's selection of Ice Energy's solution is truly a win-win for all stakeholders," said Frank Ramirez, CEO of Ice Energy in a statement. "Member utilities can better meet their goals to reduce peak demand, ratepayers are protected against the rising costs of peak power, and the growing supply of clean off-peak wind generation can be more reliably integrated."

The idea, of course, is to use power more intelligently. Air conditioning isn't the only beneficiary, either: other renewable energy sources may eventually see a "storage" aspect to combat uneven usage patterns.

Installation of the systems will begin in the first half of 2010 and take two years to complete.

This post was originally published on Smartplanet.com