Ice air con system aims for cool on the cheap
Night time is the ice time
The idea is to use cheap off-peak energy at night to freeze a tank of water (or "distributed energy storage system"), then use that great block of ice to cool your data centre in the daytime. Refrigerant would circulate from the tank to the Data Aire equipment, eliminating the need to run the energy-intensive compressor and condenser during peak daytime hours.
As the warmed refrigerant comes back to the Ice Bear unit it takes up heat and its ice melts, ready for a re-freeze at night.
During off-peak hours, the Data Aire cooling system operates as usual. Together, this hybrid system surpasses the overall efficiency and performance of conventional equipment alone.
Randy Zwetzig, an Ice Energy VP, sings energetically off the green hymn sheet: “Ice Energy and Data Aire have the potential to fundamentally transform data and telecom center efficiency and reliability at a time when it is critically important. We now have a proven system that is not only cost effective and reliable, but also supports environmental initiatives with reduced carbon emissions.”
Customers can get a subsidy in California, where power utilities PG& E, Southern California Edison and Anaheim Public Utilities will help underwrite the cost and installation of the Ice Bear units in data and telecom centres throughout their service areas, both in new construction and existing facilities.
Back in May 2007, as part of its Big Green project, IBM launched its cool battery concept. This was the same idea with Big Blue talking about a phase change material - basically water with added chemicals to change the freezing point - in a fluid-to-solid-and-back-again storage device, installed between the air-conditioning system and the chillers.
The chilled air was passed through the battery to freeze its contents. When that was done the chillers were switched off and hot data centre air cooled by being passed through the now frozen cool battery.
It cooled the air, took up its heat, and the ice inside gradually melted to the point where the cycle could begin again. IBM claimed that such a hybrid system used 45 per cent less energy over two years compared to cooling the data centre without it. ®
Price efficiency isn't just about cheap night-time electricity
It's also about very, very expensive daytime electricity. especially in places like California. That's why the utilities are paying subsidies - these "negawatts" are cheaper than building new powerplants to produce megawatts at times of peak demand.
"Cheap" off-peak electricity is only a few cents cheaper than "ordinary" electricity, but expensive peak electricity is dollars more expensive.
This is nothing new, it's been around for donkey's years...
The Edwardians used to do the same thing, at the side of many lakes near old manor houses you will find an underground store for ice which is pulled off the lake in winter.