The Future of Sharing
The culture of cold storage ownership may be coming to an end. CU Boulder has implemented a successful ULT freezer sharing program, UC San Francisco is looking to move many of its samples to an off-site biorepository, and many pharmaceutical and biotech companies have begun to employ both strategies, asking their scientists to share local freezer space for frequently-used samples and to use biorepositories for samples that need to be accessed less frequently.
CU Boulder's website details their ULT freezer sharing program, where researchers can rent freezer space for as little as 25 cents/month. Christina Greever, CU Boulder's Green Labs Program Assistant and Outreach Coordinator, says of the program, "Though the Shared ULT Freezer Program takes some time and effort to administer, we [CU Green Labs] feel that the benefits to the campus far outweigh the costs. The program is tackling culture change by encouraging labs to share their most precious equipment".
Sharing freezer space not only helps reduce energy consumption, but it also reduces waste as well. By not purchasing new equipment, raw materials are not used to create something new, all of the resources that would have been used to run the equipment are not expended, the valuable space that the equipment would have occupied remains open for some other use, and the lab maximizes its economic resources. In addition, the equipment that is being shared is being used to its fullest potential.
Sharing cold storage space should not be an innovative best practice. This Freezer Challenge, help make this a standard practice by opening up your (freezer, refrigerator) door to a colleague.
The Most Energy-Efficient Freezer is... A Chest Freezer?!
That's right. The most energy-efficient type of freezer is a chest freezer. Why is that?
There are two main reasons why chest freezers are more efficient:
1. When the door is opened on a chest freezer, all the cold air stays at the bottom of the chest and does not escape (because hot air rises). With upright freezers, cold air is more likely to escape from the bottom during door openings. This means that chest freezers that are used frequently stay colder with less effort from the compressor.
2. Chest freezers are often made out of plastic material and not stainless steel. Stainless steel conducts heat and is a less effective insulator. This is why chest freezers will often consume less than half of the energy of an upright freezer even if neither is being opened.
Does this mean you should switch to a chest freezer? Not necessarily. There are many good reasons why upright freezers are so popular, ergonomics being one of them. But it does mean that if you have a chest freezer - even if it's a really old chest freezer - it's likely using very little energy compared to a new upright model. If it still works, and you're still using it, hang onto it and show it some love for quietly doing its job as efficiently as possible [it's Valentine's Day, we couldn't resist ;)].
This week's blog post comes courtesy of one of the original founders of the Freezer Challenge, Allen Doyle. When Allen was at UC Davis, he and Kathy Ramirez-Aguilar of CU Boulder had the idea to start a friendly freezer competition between their universities to see who could save the most energy. Their friendly competition has become the International Laboratory Freezer Challenge.
Read Allen's post below for some great tips on reducing ice build-up in your freezers.
Blast the Ice Jam
Ice build-up blocks access to samples, indicates a leak gasket, or inhibits freezer performance. Blast the ice jam this month as part of the Freezer Challenge!
Clean off the door frame and gasket, and sweep off the shelves.
The good news? You don't always have to do a complete defrost. Here are some quick tips for removing ice:
When is it time for a defrost?
Defrosting freezers has been likened to cleaning out the garage, except most people prefer the latter. Looking into research freezers, you might think that ice build-up is a good thing. Maybe it 'proves that the freezer is working' or 'insulates the freezer when the door is opened'. In fact, rapid ice accumulation in your freezer may be the result of a leaky door gasket, too many door openings, or neglect... Rather than protecting the freezer, large amounts of ice may force your freezer to have to work harder than usual to maintain temperature, and it may lead to warm pockets because of poor air convection.
If you can't access samples easily, have clear ice build-up, or have more than 1/2 - 1 inch of frost on shelves and samples, it's definitely time for the Big Thaw.
What's the best way to defrost a freezer and protect samples?
Take care of your samples by temporarily storing them in a freezer with extra space. Some universities even have spare freezers that you can use, just check with your department. You can also put them in coolers or walk-in freezers, pre-cooled with dry ice and more dry ice on top.
To defrost a freezer, Dacko recommends "defrosting the freezer for 48 hours with the door ajar, and then restarting the freezer. Sometimes this will take care of temperature issues", he adds.
At the Freezer Challenge we recommend using basins and adsorbent towels placed around the freezer and under the open door to avoid puddles on the floor. We suggest using cloth towels and/or reusable adsorbent pads. Setting up a fan in front of the open door will accelerate the defrost.
Our lab is busy! When will we find the time to do this?
Try 'Freezer Fridays', an idea conceived by the Michaelson Group at UC Davis. Pick a two-hour block of time to bring the group together for freezer scrape-down, sample cleanout, and eventual defrost. Try this for one month and see what you discover hidden in your frosty freezer...
Removing ice from freezers allows the compressor to work faster, leading to longer compressor life (aka longer freezer life) and reduced energy use. Whether you choose to do a complete defrost, or simple remove the ice shelf-by-shelf, we at the Freezer Challenge award points to labs that do the smart thing and properly maintain their freezers.