Sustainably cool: Meeting the 'Freezer Challenge' in immunology research

The task of streamlining freezers and ensuring they are used efficiently is a tough one, especially if they are located over 30 labs across two hospital wings and several floors. For the last two years the SIMS have achieved Silver status in LEAF accreditation which places a strong emphasis on freezers and their use. The School labs have also taken part in the Freezer Challenge – an annual competition that aims to help entrants learn how to enhance energy efficiency and save costs through sustainable lab cold storage practices.

“We didn’t really enter to win,” says Ian Jackson, Senior Technical Manager at the SIMS labs. “But more to focus our thinking on how to make cold storage more sustainable. Entering the challenge made us count the number of fridges or freezers across all our laboratories and think about how we use and maintain them.”

As part of the Challenge the SIMS labs discontinued a number of freezers or replaced them with more efficient models, taking advantage of the King’s ‘two for one’ freezer exchange scheme where two older units can be exchanged for one modern freezer. They also reset temperatures of ultra-low freezers from -80 C to -70 C. “That final ten degrees uses a lot of energy,” explains Ian. “And for the vast majority of work we’re doing there’s no scientific advantage for -80 C compared to -70 C.”

Behavioural changes around freezers

Alongside the changes in number and type of freezer Ian and his team have also encouraged behavioural shifts in the labs. Generally there is reluctance amongst scientists to declutter their freezers and throw away old samples, even when they belong to a researcher who no longer works at the lab. As a solution the LEAF has introduced ‘exit policies’ to its accreditation checklists which require scientists to identify which samples should be kept when they leave and whose responsibility they are.

Cleaning of filters and door seals on freezers every two months is another policy the labs have introduced, alongside encouraging the reorganisation through the use of racking systems to improve efficiency. Recently a lab within King’s showed that a well organised -70 C freezer can use half the energy of a poorly maintained -80 C unit. There are also initiatives to facilitate the more intensive form of maintenance – defrosting - through provision of emergency freezers to store contents during the process and providing kits containing buckets, tools and cloths.

Recycling and waste management

Alongside the work on freezers, the SIM labs have expanded their recycling activities and improved waste management, getting advice and support from King’s climate and sustainability team to ensure that items such as plastic media, glass bottles and packaging are recycled. They are also taking actions to reduce the amount of waste going into yellow biohazard bags for incineration and plan to start introducing tiger stripe bags for non-infectious clinical waste. The team are working with suppliers to return packaging and glass bottles, and collecting compostable packaging for staff to use in their gardens. “We’ve noticed a lot of changes in this area,” says Emma Timms, Laboratory Manager at SIMS ” Companies are trying to reduce polystyrene waste by using recyclable, triple thickness cardboard and producing sustainable plasticware that is made from renewable feedstocks.”

The technical team at the SIMS labs are also working with online platforms to recycle equipment and furniture, and applying the principles of Green Chemistry to consolidate chemical use and ensure they have accurate inventories to minimise waste. As well as helping the environment, these changes have also improved the workplace, generating a tidier and more efficient space.

This year the number of labs included in their LEAF accreditation has increased and the requirements have become more stringent so they plan to apply for the Silver award again.  

“I think LEAF is about encouraging incremental progress,” says Ian. “There’s no way you can fix everything straightaway. As a process LEAF presents a lot of potential sustainability problems to be solved and the idea is that we work towards these and eventually solve them. I think achieving  sustainability in labs will always be a work in progress but the benefits are multiple in terms of environmental, financial and social impact.”