Ice Could Be Key to Storage of Renewable Energy

Ice blocks stacked up on one another.

Liyao Xie / Getty Images

75% of our electricity goes into buildings, and much of that runs air conditioning. The entire system is built to try and cope with the peak loads that come in summer. TreeHugger has covered ice storage systems before; they simply make ice at night, when electricity is cheaper and it is cooler, so it is easier to make, and then run air conditioning during the daytime when it is hot and electricity is in short supply. This can knock the peak off the demand curve and significantly reduce the need for new power plants.

But we learned In the Calmac Booth that it can have another significant benefit: It can act as a battery for wind power.

In some areas, the wind blows stronger at night than in the day, but the nation is running on base load power and the extra power from the wind is wasted. But Icebank storage systems could use that power and convert it to ice. It then acts as a battery, storing the energy at night to cool buildings during the day. It can have a big impact:

IceBank energy storage tanks store renewable energy, like wind and or inexpensive clean efficient night-time electricity, in the form of ice for comfort cooling use during peak demand periods the next day. Reducing the peak daytime demand for electricity can cut cooling costs 20-40%, source energy and emissions are reduced and construction of new power plants and transmission lines can be delayed or eliminated.

There is nothing new about using ice to time-shift cooling loads; people used to cut it in the winter to keep foods cool all summer. Systems like Calmac's Ice Banks are just time-shifting on a daily basis, making ice when the making is good, when it is cooler and the power is available, and using it when they need it during the day, when it is hotter and there is a lot of demand for electricity. Another way that the lessons of the past can be a template for the future.