Refrigerators and freezers are not at all that exciting. How about 732 of them? That’s how many units are housed in the Medical Sciences Building (MSB) at U of T, according to Tim Lang and Adebukola Olatunde.

As a prominent research facility, MSB is home to eight scientific departments, with 241 labs/offices, and a medical supplies store. The prominence of refrigerators and freezers, ranging from -80oc to 4oc units, exert their importance as storage for samples, buffers, and experimental kits. However, their presence is not cheap, monetarily or electrically.

When pooled together, all 732 units have an annual primary electricity consumption of 1636 MWh, costing $163,600 each year. -80oc freezers constitute 64 per cent of the annual power consumption, although they comprise only 16 per cent of the total number of units. In comparison, 4oc refrigerators, which also account for 16 per cent of the units, only contribute to four per cent of the power consumption.

In addition to this primary electricity consumption, there is also an associated cooling load. Specifically, air conditioning systems must produce an extra 195,409 tons (costing $27,800) to offset the heat produced by the refrigerators and freezers.

According to the authors of the initial report, replacing all consumer grade units with more energy efficient products is not financially viable, since the payback would take approximately 30 years and result in an annual savings of only $8,500. A more feasible option involves a 15-year payback that would require replacing the ancient units (pre-1978!) and fridge-freezer hybrids (from 1978-1993) to reduce annual costs by $6,000.

What if, instead, administrators of MSB adopted the approach taken by U of T’s Athletic Centre, as reported by Tim Ryan in last weeks issue (http://thenewspaper.ca/the-science/item/170-ac-solar-panels) To recap, 100 new solar collector panels were installed at the AC in order to generate energy to supplement their needs. During peak sun-hour months, the panels are expected to produce enough energy to support 25 per cent of the heat used by shower and laundry services.

Assuming the same system could be installed at MSB, with an output of 208 MWh/year, I calculate an annual reduction of approximately $20,800 in the electricity bill. Agreeably, the technology has a significant initial cost, but in the long term, it will pay for itself--and contribute to reduced green house gas emissions.

Refrigerators and freezers, not so boring after all.