Just how much energy does an office freezer-fridge use?
A lot. An average refrigerator from 1996 uses close to 1,800 kilowatt-hours of electricity while a modern energy-star rated refrigerator uses as little as 450 kilowatt-hours. Great, but what is a kilowatt-hour?
A kilowatt-hour is a way the power company measures how much electricity you use. Think of it like this: imagine you were billed for how hot you like your shower water and how long you used favorite temperature of shower water. The hotter or longer(or both!) you shower, the bigger your bill. The same is true for electricity, the more you use and the longer you use, the more power company will bill you for. A kilowatt-hour is just the combination of how much (kilowatts) and how long(hours) the electricity was used.
Now back to our refrigerator comparison – the 1996 model could cost upwards of $22 per month to operate, while a modern refrigerator could cost as low as $4 per month. That’s money back in your pocket plus big savings on carbon emissions! Want figure out how much an appliance uses? Check out this online calculator to see how much your favorite appliance costs you.
Sample storage in research labs can use as much energy as your house.
Some research labs us ultra-low temperature freezers (ULT freezers) to keep samples and specimens safe. These are much colder than the typical household freezer. Ultra-lows can get as cold as -125°F / -85°C. At these temperatures DNA and living tissue can be preserved for long periods of time without degrading. Keeping things this cold uses a lot of energy, sometimes as much as your entire home everyday!
Here are some ways to save:
- Increasing the temperature of an ULT freezer from -80°C to -70°C could save up to 30% electricity usage. To put it another way, three ultra-low freezers at -70°C use the same amount of energy as 2 ultra-low freezers at -80°C.
- Many reagents and samples, like DNA, can safely be stored at much warmer temperatures and do not needed an ULT freezer. Using a -20°C freezer versus a -80°C saves up to 80% on electricity usage.
- Make sure to properly ventilate a ULT. Freezers in hot, stuffy rooms use more energy to keep their contents cold
Interested in reducing your research activities’ impact? Considering joining the freezer challenge!
The Freezer Challenge: a cool way to reduce the environmental impact of your research
Each year, scientists across the globe join and compete in the International Freezer Challenge. Kicking off in January, scientists take the next six months to brainstorm ways to be more energy efficient, save their institutions and employers money, and improve safety. Chilled storage is the second largest energy consumer in a research lab; fume hoods are the number one consumer of electricity. After six months of saving energy, scientists submit their score cards and winners are announced. Judges choose winners and runner ups for each category:
- Academia
- Biotech & Pharma
- Hospitals, Clinical Research, Private Companies
- Government Research
The Freezer Challenge held its first contest in 2017, and since then over 24 million kilowatt-hours have been saved. That’s over 16, 796 metric tons of carbon emissions saved. Make your lab a green lab by signing up for the Freezer Challenge!
Quick tips for increasing freezer / fridge efficiency
- Regularly defrost freezers, remove ice near door seals, and clean dust off coils and heat exchangers
- Adjust the temperature warmest your samples, specimens, and reagents
- Upgrade or retire old, under-used units, combine or share freezer space with others
Old fridges may contain toxic or ozone depleting chemicals, make sure to properly dispose of old units. Go here for disposal options.
Have questions about your lab or office fridge? Looking for advice on how to upgrade or dispose of a unit? Contact the Safety & Sustainability team!
EHS Director: Ronnie Souza | rsouza@une.edu | 207-602-2488
Associate Director of Sustainability: Alethea Cariddi | acariddi@une.edu | 207-602-2507
EHS Specialist: Peter Nagle | pnagle@une.edu | 207-602-2791
EHS Specialist: Davis Martinec | dmartinec@une.edu | 207-602-2046