The Ice Bear

This ingenious device from Thule Energy Storage enables customers to be
more strategic about their electricity consumption.


The now ubiquitous smart meter ushered in the era of time-of-use pricing, enabling the local utility to charge different rates for different parts of the day. Time-of-use pricing typically breaks the day into three time periods — Peak, Off-Peak and Mid-Peak — with different rates for each. The goal is to encourage residential and business customers to use less during peak periods by offering lower rates in the non-peak hours.

In the hot summer months, air conditioning is a major pull on the electrical grid. And this past summer was particularly hot just about everywhere. Spain and several other European countries have told their citizens they must turn down the air conditioning. In Spain, the mandate states that air conditioning in public places be set at or above 27 degrees Celsius (a little over 80 degrees Fahrenheit) and that building doors in those places must remain closed to save energy. This includes offices, stores, bars, theaters and transportation stations, and is a recommendation to all Spanish households as well. Looking forward to the winter months, it instructs that building heating should be at or below 19 degrees Celsius (about 66 degrees Fahrenheit). The mandate will remain in effect at least through November 2023. Compared to that, the “gentle” suggestion the time-of-use tiered rates makes to lower energy use in peak period seems rather friendly … but those rates do add up.

Meet the Ice Bear
The Ice Bear from Thule Energy Storage starts with a simple principle: Enable customers to be more strategic about their electricity consumption from air conditioning by taking advantage of times when utility rates are lowest to save money, with the additional benefit of taking strain off the grid in the peak periods.

Thule Energy Storage describes the Ice Bear as a “distributed ice-powered battery.” The Ice Bear “charges” up at night when energy rates are lower by freezing ice in an insulated tank. The ice cooling is then used during the day when the customer needs cooling the most, typically during the Peak electricity consumption period. When engaged, the Ice Bear automatically turns off the air conditioner’s compressor and provides the ice-cold refrigerant to the AC unit. At night when rates drop it re-freezes the stored ice, ready to repeat the cycle.

The Ice Bear is available in two configurations: The commercially targeted Ice Bear 40 can accommodate multiple HVAC configurations, while the Ice Bear 20 is an all-in-one air conditioning and thermal energy storage unit designed to fully replace residential condensing units. It supports residential applications from traditional ducted systems to those that use ductless mini splits. Both the Ice Bear 20 and Ice Bear 40 feature a smart grid controller and mobile connectivity to provide real-time control and programming. The units have an economic life of 20+ years and offer an additional benefit of improving the life of the air conditioning and HVAC system by reducing compressor cycles. And the units do not rely on hazardous chemicals; much like the ice in your refrigerator, the storage medium is tap water. To date, more than 1,500 units deployed comprising over 20 MW of storage capacity.