About This Project

We have often wondered why we have a refrigerator/freezer appliance running a compressor to keep the chamber cool on days when the temperature outside could do the job for us. The temperature is below zero degrees celsius for more than 100 days of the year in more than 20 countries. If we are correct, and it's feasible to use the cold air, we could probably save a tremendous amount of electricity, reduce fossil fuel consumption, and extend the life of appliances and keep them out of landfill.

Ask the Scientists

What is the context of this research?

It seems wasteful when the temperature outside is -10 degrees, and we are using electricity to heat our homes to 22 degrees, and yet more electricity to cool a box in the kitchen to 0 degrees again. The fridge/freezer doesn't throw off enough waste heat to be considered an advantage in heating the home, so why don't we just re-use the outside air?

What is the significance of this project?

Any energy-saving project has a cost to implement and a cost to run compared to the usual way of operating. Replacing a $1 light bulb with a $6 LED bulb may change the power consumption from $12 per year to $1.50, so the payback is within the year, and it's relatively risk free.

We know we can use the outside air with a well-designed pump like this, but with the cost of the device (and installing it), the results of our experiment will determine whether it's worth it. If our calculations are correct, we can offer a $500 device to the consumer with a $250 installation charge that they will see "paid back" in energy savings in 18 months. This would apply to anyone living in the Northern regions of the world (USA, Canada, Russia, Norway, Sweden, Denmark, etc.)

What are the goals of the project?

We will buy three of the same appliance. We will install the enhancements in the freezer of one device, and another in both the freezer and refrigerator compartments. One will be unaltered as our control. Our insulated tubes will run from the freezers to the outside during the winter, when the temperature is between -5 C and -25 C. We will also measure the power being consumed by each appliance during these times. Thermometers inside each of the appliances will make sure the temperature is consistent with, or better than the conventional appliance (or we risk the food safety). We will also put food in the chambers to see if the taste is affected over time. We will open and close the doors regularly to simulate normal use. At the end of a month we will have enough data for a conclusion.