If they can pull it off, sheets of ice will soon cover large swaths of the California power grid.
The Southern California Public Power Authority and Ice Energy will tomorrow talk about a strategy to deploy ice air conditioners on a broad scale in the region in part by shifting the burden of paying for a new air conditioner from the building owner to a utility. In one community in the program, a utility will pay for the air conditioners and own them as its own asset.
Collectively, the air conditioners slated for deployment in Southern California could lead to 53 megawatts worth of energy storage. Put another way, the air conditioner/energy storage units could provide 64 gigawatt hours of daytime power each year. Fifty megawatts of power can be shaved from daytime demand with about 5,500 of the company's Ice Bear units, executives have said.
Ice air conditioners work by effectively shifting the power required to run air conditioners from the middle of the afternoon, when power costs the most and demand is highest, to nighttime, when utilities often have to dump the power they generate because of slack demand.
In short, the machines make ice at night. As it melts, the chill is transferred to heat exchangers and distributed through a building. The six hours of chill the ice can provide can ideally get most buildings though the bulk of the day. The giant icemakers often sit beneath parking lots.
Ice air conditioners have been around since the 1920s, when movie theaters used to deploy them to draw crowds on hot summer days. (And long before that, Roman Emperor Varius Avitus had snow mounds brought to his garden to generate cool breezes. It was a highlight of his reign -- Edward Gibbon and others rank him as the worst emperor Rome ever had.) In more recent times, ice air conditioners have been placed in shopping centers and university buildings.
Still, ice air conditioners represent only a fraction of the market. Ice Energy has been pushing to accelerate sales by changing incentives and ownership structures. The company used to sell the systems directly to building owners. Unfortunately, payback can take years, if it ever takes place at all. Some ice air conditioners actually use more power than regular air conditioners: unless a building owner participates in a net metering program, they could end up being worse off.
Utilities, however, consistently benefit from them because of the reduction in peak power demand they can create. Air conditioners can account for as much as 50 percent of electricity consumption in California, and even more in hotter places like Dubai. As a result, Ice Energy shifted strategies and began to sell its units to utilities as devices for peak shaving. In this light, the ice air conditioners function like demand response systems, eliminating a chunk of daytime power needs, without the networking. It just happens on a daily basis.
Three U.S. representatives last year proposed a bill that would provide business owners and consumers a 30 percent tax credit for installing ice systems as well, which would help spur demand in places where utility-based programs don't exist. It could also help defray costs for the utility.
Calmac, which also makes ice air conditioners, recently installed a giant system in New York's Bank of America building. Now, the only thing the market is missing is an endorsement from Otzi, the ice man of the Alps.
The discussion takes place Wednesday at 10:00 PST. More here.