TreeHugger has covered how Zero Energy Buildings should make nice with ice, but we linked to CALMAC, which makes commercial products. A decade ago, John Laumer wrote about the Ice Bear, a residential unit. There were no smart meters back then and no peak and off-peak power rates, so the benefits came from the fact that it takes less energy to make ice when it is cooler at night. It’s a very different story today.
Ice Energy, which still makes the Ice Bear, now claims that “Ice Energy’s home ice battery provides 24/7 efficient cooling for your home and can cut your bills by up to 40%! You start saving from day one and your carbon footprint melts away as your Ice Bear comfortably cools your home.”
It’s hard for some to think of ice as a battery, but it is- it takes power during off peak times (perhaps from solar panels on your own roof) and makes ice. Since air conditioning is such a big consumer of electricity, it is storing the energy needed to cool the home as ice instead of electrons, and releasing that energy at peak power times, just like a conventional battery would. But there are real advantages:
Ice batteries cost less than half of lithium ion batteries of the same capacity on a life-cycle basis. They can eliminate the need for expensive peaker plants, and new transmission and distribution upgrades. Customers save up to 40% on their cooling bills too.
Because it is just water changing state instead of the chemical reaction that happens in batteries, it can last much longer.
While chemical batteries degrade over their relatively short life, our ice batteries last at least 20 years and suffer no degradation, regardless of use. They can be fully charged and discharged everyday for up to 20 years without any capacity loss.
They have a much longer track record, too.
Ice Bear storage is commercially-proven. Since 2005, our smart ice batteries have logged over 34 million operating hours with a reliability record in excess of 98%. Our ice batteries were built to last and require minimal maintenance.
Of course, TreeHugger wishes people would invest in radical building efficiency so that they only need a teensy little air conditioner instead of a big ten ton unit, and where the whole house can act as a thermal battery. And it would be nice if it was a split system with the condenser outside but the ice storage unit inside, possibly increasing efficiency by keeping it all inside.
But if we are serious about reducing peak loads and storing solar power, this is another interesting tool.