The load hiding in plain sight
Walk into any supermarket and you are walking through one of the most energy-intensive buildings in the commercial sector. Refrigeration accounts for 30% to 60% of a supermarket's electricity consumption (UNIDO), and some studies put the figure closer to half. Meanwhile, a typical Canadian indoor ice rink consumes around 1.5 million kWh of equivalent energy a year, with refrigeration taking the largest share (Natural Resources Canada).
These loads run around the clock, and they run hard during the exact hours when electricity is most expensive. Yet they are among the most flexible loads a building can offer. Why? Because cold is stored energy.
Thermal mass: the battery you already own
A freezer case full of frozen peas is a thermal battery. So is 30 tonnes of ice. Once food or ice is brought down to temperature, it takes hours to warm up by even a degree — which means the compressors do not need to run continuously. Equipment manufacturers have said it plainly: supermarkets, with the considerable thermal mass of cooled food, can play a stabilizing role for the grid by adjusting their consumption (Danfoss).
In practice, that flexibility shows up in three ways:
1. Pre-cooling before the peak. Drop case and room setpoints by a degree or two ahead of the expensive hours, then let the system coast. The product never leaves its safe temperature band, but the compressors sit out the peak.
2. Shifting defrost cycles. Defrost is pure resistance heat — the most expensive kind. Scheduling it outside peak windows is often a configuration change, not a retrofit.
3. Sequencing and modulation. Variable-frequency drives on compressors, condensers and evaporator fans let the plant ramp rather than slam on and off, trimming both energy and the demand peaks that drive a big share of commercial bills.
Research on a Canadian indoor rink found that price-based control of the refrigeration load — forwarding or delaying thermal loads in response to electricity prices — cut yearly electricity costs by up to 11.6%. No new equipment. Just smarter timing.
The heat bonus
Every kilowatt pulled out of a freezer case is rejected somewhere — usually dumped to the outside air as waste heat. Recovered, that heat can warm the sales floor, preheat domestic hot water, or melt the snow at the arena entrance. The Westhills Recreation Centre in Langford, B.C., found its ice-plant waste heat was more than enough to cover all of the building's heating loads, with surplus shared with a nearby housing development.
What this means across Canada
The opportunity scales from coast to coast: grocery chains with dozens of stores, food distribution warehouses, and the thousands of municipal arenas that anchor Canadian winters. Time-of-use and demand-based rates — in Ontario, in Quebec's dynamic pricing, in B.C. — all reward the same behaviour: consume less when the grid is stressed.
Refrigeration is also one of the easiest loads to bring under centralized control. Compressors, valves and sensors already speak open protocols, and once the data flows into one place, a whole portfolio of stores — or rinks — can be orchestrated as a single flexible asset. Platforms like Tenergen OS treat a rack of compressors the way the grid treats a battery: charge it (pre-cool) when power is cheap, discharge it (coast) when it isn't.
Getting started
You do not need a new refrigeration plant. Start with metering on the compressor racks, confirm your safe temperature bands with your refrigeration contractor, and pilot pre-cooling and defrost shifting on one site. Measure the peak reduction, then roll it out. The cold was already there — now it is working for you.