Freezer Challenge

A laboratory freezer can use as much energy in a year as a residential home! 

You can help reduce your lab’s environmental impact by joining the global Freezer Challenge.

U-M Freezer Challenge

The Freezer Challenge is a competition designed to promote best practices in cold storage management. U-M has thousands of freezers, which are a major contributor to our greenhouse gas emissions and energy costs. Best practices also benefit researchers directly by reducing costs and freeing up space for new samples.

The competition is run by My Green Lab and the International Institute for Sustainable Laboratories. Our role is to provide personalized, U-M-specific support and additional incentives to help U-M participants complete the challenge. 

Why Participate?
  • Reduce your lab’s carbon footprint 
  • Learn proper cold storage maintenance techniques to help avoid future failures
  • Reduce the cost of maintaining extraneous cold storage units
  • Removal of unneeded or unviable samples from cold storage units frees up space for new samples without the cost of purchasing additional refrigerators and freezers
  • Recognition and awards! (Did someone say pizza party?! Yep, that’s one way winners can celebrate.)
How to Participate

Sign up at Use your or email address so we can identify that you are participating and add you to the U-M Freezer Challenge newsletter. (If you do not wish to join the U-M challenge, please email [email protected] after registering.)

The global competition organizers will provide instructions to complete your score sheet by July 1, 2024.

OCS will send you a window cling and periodic email newsletters with U-M-specific resources. 


The International Laboratory Freezer Challenge (Freezer Challenge) is a competition designed to promote best practices in cold storage management. The Freezer Challenge covers all forms of cold storage, including refrigerators, freezers, and cold rooms. Labs participating in the challenge will be asked to submit an online score sheet. To learn more, check out this introductory video

Any laboratory in the world can participate by signing up at Laboratories are defined as a group of people and their physical space working under one manager, researcher, or scientific mission.

The Freezer Challenge runs January 1 to July 1. Scoresheets will be due by midnight PST on July 1. Labs are encouraged to work at their own pace to complete the Freezer Challenge during the intervening months.

Absolutely! Many labs register for the competition in February, March, April, May, even June. You can count any actions on your 2024 scoresheet that your lab has done since August 1, 2023, so if you cleaned out samples, defrosted units, updated inventories, or any of the other best practices from August 2023 until now, you can count those on your scoresheet. Therefore, there is no disadvantage to registering after January. Go for it!

Freezer Challenge participants will benefit from:

  • Reducing energy consumption, costs, and environmental impact of the lab
  • Learning and applying proper cold storage maintenance techniques to help avoid future failures
  • Removal of unneeded or unviable samples from cold storage units, freeing up that space for new samples without having to purchase additional refrigerators and freezers
  • Reduced costs associated with maintaining extraneous cold storage units
  • Improved researcher access to and security for viable samples
  • Participation recognition, plus awards!

Labs will receive points for taking the actions listed under Best Practices part of the website, which mirror the Freezer Challenge scoresheet. In the vast majority of cases, each action per cold storage unit is worth 1 point unless otherwise described on the scoresheet.

For actions that also have an energy savings component, I2SL also estimates kwh/day saved. Once you submit your scoresheet, you will receive a preliminary estimate of your energy savings. 

The Freezer Challenge is scored by looking at a combination of factors, including points earned, kWh saved, points earned per cold storage unit, and kWh saved per cold storage unit. The goal is to reward the labs and organizations that have earned the most points and saved the most energy through the Challenge. New this year, I2SL has a more in-depth explanation of scoring methods.

For the U-M competition, the winners will be the 3 labs with the largest percent energy reduction. 

  • Yes! The I2SL Freezer Challenge is a global competition. There are awards for winning the global competition. Also check out the How to Win the Freezer Challenge guide.  

    U-M is also holding an internal competition. Details are being confirmed, but all participants who complete a score sheet will receive recognition and the top three laboratories will receive prizes!

No problem! Email [email protected] with "reopen scoresheet" in the subject line and the support staff know that you need access to your scoresheet again.

In some cases, yes, such as if your ULT freezers are already set to -70 °C. For many scoresheet elements, I2SL asks participants in the 2024 Freezer Challenge to only report actions your lab has done since August 1, 2023. This system of reporting rewards the labs and organizations that have done the most actions in the past year, all the way up to July 1, 2024. Many of the preventative maintenance best practices highlighted by the challenge, as well as sample management strategies, should be done on a regular basis in all laboratories, so we are encouraging that by requesting that labs only record actions they've taken in the previous year.


Medical School labs, please email [email protected]

All others, please email [email protected]

Check out this video on basic freezer maintenance (start at timestamp 1:20). It describes simple steps that are approachable for most people. If you feel that you require additional assistance or are concerned about the operation of your equipment, please describe your issue and we will direct you to the appropriate resource. 

The Office of Campus Sustainability has a program that may be able to rehome equipment and supplies you no longer need. Email [email protected] with a description of your items to see if they can be accepted. Please include your location and preferred pick-up time and day.

All questions related to the I2SL Freezer Challenge, score sheet, and portal should be directed [email protected].

For questions related to U-M freezer support, maintenance, or the internal U-M Freezer Challenge, please complete this form and someone will be in contact with you. 

Questions? Fill out this form and we’ll be in touch. 

2023 Impact

69 U-M freezers impacted

Annual electric cost savings: 102,000 kWh/yr

Annual avoided emissions: ~30 metric tons of carbon

Annual cost savings: $10,500/yr

Freezer Tips
Check out these tips to optimize the performance and efficiency of your lab’s ultra low temperature freezers.