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Ultra-low temperature freezers (ULT Freezers) typically operate between -70 and -80◦C, consuming between 16-22kWh per day, around twice the consumption of an average UK household! They are, therefore, some of the most energy intensive pieces of general laboratory equipment. In the Clinical School these storage facilities are essential for storing or archiving biological samples.

Recently a Green Impact team at the Clinical School initiated a project to carry out an audit of the current ULT storage facilities and to identify ways to improve their efficiency. The group, led by Professor Nick Wareham, discovered that departments within the Clinical School are directly responsible for 444 individual ULT freezers, based in 161 different rooms across 23 locations. These 444 ULT freezers are responsible for just under 4 million kWh of energy per year, costing roughly £460,000! This is equivalent to around 3% of the total electricity consumption of the University’s operational estate.

Managing these storage facilities more effectively could help to significantly reduce both the University’s carbon emissions and electricity usage. Therefore the Clinical School, as a result of this report, are considering consolidating their ULT storage, and replacing older units with newer more efficient ones. The Clinical School are also encouraging better management of freezers across the school and for users, where possible, to raise the temperature of their freezers from -80◦C to -70◦C. This 10◦C rise in temperature can reduce the energy consumption of an individual unit by 30%. They are also looking to introduce electronic inventory systems for all samples stored in ULT freezers.

This project has recently been submitted under the Green Impact Excellence award scheme, the results of which are being announced on 2 June. Stay tuned for details of the award winners in next month’s Greenlines, plus plenty more good news stories about what Green Impact teams have been up to in other departments!

If you work in a lab, why not download or request a copy of our ‘Five ways to safeguard samples’ poster or our ‘cut energy not research’ poster? You can find them both on our materials page.