Ultra-low temperature (ULT) freezers are an essential resource in medical science, as they allow biological samples and vaccines to be preserved safely at very low temperatures. Many lifesaving vaccines, including the Pfizer (COVID-19) vaccine, require ULT freezers for storage and they are vital to research laboratories, including ours here at King’s, where we have over 550!
Like any cooling, freezers are extremely energy intensive, particularly ULT freezers. Depending on their age and model, these freezers can use the same amount of energy as the average UK home and require further energy to cool the spaces they occupy. Beyond the impact of the energy consumption, cold storage devices utilise refrigerant gases, which are HFCs. While these gases are far less harmful on the environment than their predecessors (CFCs), they can still wreak havoc if released into the environment. In the UK, there are regulations in place to avoid their release, but old equipment can still lead to leakages.
So, what can we do to manage our ULT freezers sustainably?
Procure energy efficient freezers - To start, we can aim to purchase more efficient units. At King’s, we promote sustainable procurement both through our tender process and sustainable lab programme (LEAF).
Manage samples efficiently – Storing our samples efficiently means we can maximise our freezer space. King’s Department of Women & Children’s Health have recently transformed their sample management system by adopting microtubes that take up less than half the space of previously used containers. This has had the dual effect of increasing the internal capacity of each freezer and reducing the volume of plastic required. Shared around the college, this practice is now being adopted by others, including groups within the School of Basic & Biomedical Sciences.
Store only what we need – By removing samples that are no longer needed we can consolidate our holdings. To support this, King’s Freezer Replacement Scheme offers to pay for new, ultra-efficient, fully-racked ULT freezer if researchers can consolidate the contents of freezers in their area, so that two older freezers can be taken away in exchange for one new energy efficient one. This scheme aims to reduce carbon emissions and encourage the adoption of efficient management system.
Good housekeeping - Smart freezer management goes a long way! Our Good Practice Guide provides some great tips and tricks on maintenance such as defrosting and clearing filters.
Reduce the temperature – Check what temperature the freezers are set at. While many operate at -80°C, historically they all were set to -70°C. That 10°C difference leads to an impressive 25-30% in energy saving, and has been implemented in some of King’s sites like the Wolfson Centre for Age-Related Diseases.
As our research and laboratory practices grow, we must ensure that consideration is given to the impacts on the environment and integrating sustainable practices such as those listed above is crucial to delivering impactful research, while minimising our environmental impact. Whether you are directly involved in freezer management, or have a supporting role, we can all play a part in sharing this knowledge and raising awareness amongst our peers, which in turn can go a long way in creating a wider mindfulness about their environmental impact and how we can support a more sustainable infrastructure at King’s.
Laboratories are filled with a variety of equipment types, many of which are communal so that they may be utilised by multiple groups and departments. Due to this communal nature and irregular working hours, equipment is frequently left on unnecessarily. Furthermore some types of laboratory equipment are particularly energy-intensive and thus finding ways to turn them off where possible could reduce energy consumption as well as potentially increase the life-time of the equipment. While not applicable to all equipment, a simple solution to this would be to apply plug-in timers to certain devices. Pictured here, plug-in timers come usually with 24-hour or 7-day programmes.
At the end of 2014*, the Sustainability department purchased 50 7-day digital timers for installation in laboratories. 7-day timers were preferred to 24-hour devices as permitted further flexibility to reflect the variable working schedules of the research community. Timers only cost ~£6.20 per timer bringing the cost to ~£315 in total. Devices targeted had to be of a specific nature – ie. equipment that did not house live samples overnight, no fridges or freezers, and nothing that potentially need to be run overnight. Incubators of any sort were not suitable for installation. Drying ovens, cabinets, and heating blocks commonly left on were prime targets for such timers. Water baths are commonly left on in research spaces and when metered can consume between 1-3 kWh per day. While they consume low amounts of energy, it was calculated that a water bath left on for just ~25 days could pay back the cost of a timer. Thus water baths were suitable for timers. Note a typical timer should have a lifetime of 5 years minimum.
There were a few lessons learnt from the project. Firstly not all the timers purchased worked perfectly. It’s worth engaging with your research colleagues to ensure that if a timer is faulty, you can replace it with another promptly. It’s also good to engage the staff about any timers installed to ensure they’re comfortable with the schedule chosen and the equipment being targeted – some ovens will take live samples and some won’t. Furthermore different laboratories have different working schedules, so ensure the schedule chosen best reflects the settings. Finally, it may be worth discussing with your research colleagues a year on if they’re still in use. A timer may frustrate a user and get unplugged, and it’s good to ensure that you get the best use from your investment.
Overall we bought 50 timers, and 45 of them worked in the end. Of those 45, the estimated savings are ~£3,100 per year. We may have to look for different targets on some of them, as some drying cabinets they were applied are being replaced with newer insulated cabinets with timers built in, but from such a small investment it seems an easy win for research spaces.
*Update, since this project has been written, another 100 timers have been bought and distributed across the college each academic year since. Labs taking part in the Sustainability Champions programme are automatically on the list for new timers.
Savawatt devices are fitted to equipment such as fridges and freezers, and have shown to reduce energy consumption of fridges by ~14%. King’s Sustainability has invested £38,000 to install these devices across laboratories. With estimated annual energy savings of ~£15,000 and a lifespan of 10+ years, Savawatt devices are expected to result in significant energy savings.
Envision Concepts has developed a patented, Salix approved device called a savacontrol which can match motor needs to energy output in any equipment with a compressor (ie fridges and freezers, though for this project we did not include ULT freezers), and in doing so achieve energy savings. They are easily installed at the plug-level and can endure for 10+ years. Previously Kings College London had already organised an installation of such devices where appropriate (buildings with higher voltages, above ~230 volts) with some success. Fridges with the devices attached showed ~14% reductions in energy consumption. This goal was to complete a wide-spread installation to target particular areas in the Guys Hospital and Denmark Hill Campus.
The project was a success as a large installation tallying approximately £38,000 was organised and managed by the Sustainability department with an estimated 2.4 year payback period. 584 refrigerators, -20C° freezers, and walk-in cold rooms had devices fitted (mostly fridges and freezers) throughout research spaces, as well as one sports facility. To improve payback, areas with particularly high voltages were targeted (for e.g. some areas surveyed were found to be running at 246 volts!). The project was not without its barriers. Of particular difficulty was managing the installation during the opening of the new Wohl Institute as many of the fridges/freezers initially surveyed were moved to this new space. The Wohl Institute was not appropriate though for savawatt installation as it did not have a voltage high enough to give a good payback. There were no reported break downs or equipment failures associated with the installation, although it did highlight issues with one cold-room these were pre-existing. To avoid researchers removing the devices, they were closely consulted about the installation. To avoid waste of a savawatt device, they were fitted where possible with stickers with contact information to the sustainability department to ensure that if the fridge was replaced, a suitable replacement could be fitted.
Currently, this remains an easy and tested method to achieve energy savings in research and cooking spaces where fridges and freezers are common. With an estimated ~£15,000 saved annually in energy and a 10+ lifespan of savawatt devices, we hope to incur significant energy
Cold Storage Policy
In attempt to better understand cold storage costs at King's and spread good practice, a set of surveys were conducted followed by the implementation of a cold storage policy.The goal of this work was to ensure the cold storage equipment selected was as efficient as possible, and also maintained and run in a similarly efficient manner.
Prior to introducing the policy most of King's research spaces were surveyed for fridges and freezers though not cold rooms or liquid nitrogen storage. Coupled with survey figures previously obtained, overall cold storage costs were estimated in non-embedded spaces (embedded being run by NHS). Results may be found below, and were presented to senior estates management at King's. The overall costs for cold storage are likely much higher when NHS run spaces and walk-in cold rooms are factored in. Note the significant costs in ‘added costs’, which is a combination of estimated costs of supplemental cooling, maintenance, alarming, and carbon tax. This does not include procurement or possible disposal costs.
The policy takes aim at procurement of efficient and reliable equipment as well as ensuring it is maintained in a manner that ensures maximum endurance. Also novel recommendations such as assessing non-ULT running temperatures are included as well as easy tips for improved efficiency (cleaning filters, defrosting seals). Currently being disseminated and implemented across KCL research spaces and will hopefully act as a guide for further institutions. It is recognised that a policy is not an outright solution to suboptimal management, but it is a clear step in the right direction. While cold storage requirements are constantly growing, ensuring they’re well managed can not only reduce running costs but also improve resilience and safety of samples and the equipment itself.
Cold storage - replacement of inefficient equipment
This case study reviews the exchange of under-bench cold storage for efficient consolidated equipment. The purchase was supplemented with funds from King's Sustainability, permitting the purchase of more efficient replacements which would benefit the laboratory, as well as the estate.
Bernard Freeman currently manages the Social, Genetic, & Developmental Psychiatry Centre’s (SGDP) research spaces, covering approximately 530 m2. Much of the cold storage in throughout the department is under-bench fridges and freezers. There were so many that they were blocking space for seating, as well as producing excess heat within the laboratory. Bernard approached the KCL Sustainability team about his interest in purchasing new cold storage equipment, and together they calculated energy payback should new efficient stand-up models replace the current under-bench models. 30 under-bench fridges (10) and freezers (20) were to be replaced by just 10 new units (3 fridges, 7 freezers). As under-bench units are inefficient in their use of space and energy, replacing the 30 units with 10 uprights actually provided much more space for samples! Instead of 3,600 litres of space, the laboratory would then have 5,310 litres, a 48% increase in space. Not only was more space afforded for samples, the units were extremely efficient in comparison, and represented a 30% energy saving in operation.
With these benefits, the team contributed to just under 1/3 of the purchase costs of the new units, calculating that the contribution would pay back in 2.5 years. After this time, the energy savings of the new units will incur savings for the estate. Now the laboratory has a dedicated freezer room (pictured above) which contains all the units together for better management of the heat load produced. Furthermore, accessible bench-space has been greatly increased.
Finally, this has prompted the energy team to provide an 'energy efficiency fund’ scheme where researchers may apply for supplement funds for efficient equipment premiums.
Fume Cupboard Face Velocity Control
When assessing laboratories for energy saving opportunities, ventilation is often quickly cited as area with great potential. Laboratories require constant ventilation for a safe and comfortable working environment.
Biological safety cabinets and fume cupboards add to the complexity of research facility ventilation as their requirements can vary frequently. While the running of the equipment itself utilises notable amounts of energy, there are greater losses in conditioned air. Much of the air that is ventilated either through rooms or research equipment has been warmed or cooled for the environment, and it is the loss of this conditioned air which can be particularly costly. Ensuring that the rates of flow are high enough to ensure safe conditions and yet low enough to not be wasteful is one of the continuing challenges in managing research facilities. With this case study from Kings College London, we take a look particularly at fume cupboard flow rates and how the introduction of one policy can significantly reduce energy waste across research sites, and save money.
Each fume cupboard maintains a ‘face velocity’, which measures in meters per second the volume of air passing through the opening when the sash is at a safe working height. Currently most fume cupboards operate with a face velocity of 0.5 m/s or above unless otherwise evidenced through containment testing. Many fume cupboards state to operate at 0.5 m/s will actually end up far higher with time. Fume cupboards are inspected every 12-14 months under law to ensure that they are maintaining safe flows and in good working condition, during which face velocities may be altered.
There are hundreds of fume cupboards in operation across 3 hospitals and 5 campuses. King's staff will work with all of them, with many managed by the NHS, PFI contract holders Bouygues, and soon the Crick Institute. Upon inspection many of these fume cupboards are operating with face velocities well above the 0.5 m/s requirement, with some buildings averaging 0.7 m/s. While still safe, such flow high flow rates will expel much conditioned air outside the building, wasting energy. Thus lowering the face velocities on all fume cupboards to a consistent 0.5 m/s could lead to significant savings. To ensure fume cupboards are consistently maintained for safety and efficiency across the college, we have introduced a fume cupboard maintenance policy. As fume cupboards will receive their annual inspections, engineers will ensure that face velocities will be maintained at a consistent 0.5 m/s (unless high velocities are required for special purposes). Furthermore new installations will have their face velocities set to 0.35 - 0.4 m/s.
Guy's Cancer Centre - The Ideal Laboratory
King’s College London conducts research on several campuses located within central London, Guy’s Campus at London Bridge. This site contains a variety of research centres, the most recent being the Guy’s and St Thomas’ Trust (GSTT) Cancer Centre. Opened in late 2016, the centre contains clinical treatment facilities able to treat 6,500 patients per year, as well as modern research facilities. The aim of the centre is to bridge the gap between promising research and trialling this research in clinical settings. As part of King’s continued partnership with GSTT, the research oncology group (part of the King’s Faculty of Life Sciences and Medicine) occupies one floor of the new centre and was previously located in the tower of Guys’ Hospital.
Lab manager Gianfranco Picco had a high level of involvement with managing the move and set-up of the new facility. Prior the centre being constructed, Gianfranco had enrolled his laboratory into the King’s Sustainable Labs programme and achieved a Bronze Award in 2015 and was devising ways to improve the operational efficiency of his laboratory.
He had observed inefficiencies surrounding how consumables were purchased in the laboratory, noting some users were purchasing £4,000 of plastics per month. Gionfranco said, “I started to think more actively around the topic after we were engaged to do the awards programme.”
Using the move as an ideal time to implement change, Gianfranco centralised purchasing of laboratory consumables. Procurement of reagents became centred around the activity or subject rather than the group or scientist. The effect was immediate, as the same group purchasing £4,000 reduced their costs to £2,500. Stocks no longer ran out during experiments as ordering was more predictive. As products were standardised, Gianfranco was able to negotiate discounts of 5-10% on most products, all of which directly benefitted the laboratory. Gianfranco said, “It started as a space saving project, but became a complete optimisation of how we procure.” The centralisation also includes chemicals, extraction kits and more.
In anticipation of the move, Gianfranco pursued further improvements to the sustainability and efficiency of the laboratories. Now installed in the new centre, the results are highly commendable and are summarised below:
To begin all equipment was tendered with efficiency standards input from the King’s Energy Team, who informed the purchase and subsequent management of energy and space efficient cold storage. In particular, Gianfranco implemented ULT operational temperatures of the new freezers to be at -70C instead of -80C. While only 10 degrees, this will reduce energy consumption by 30% on what is the equivalent to the daily energy consumption of an average UK household.
All freezers were correctly sized to permit the most efficient watts/litre efficiency, and all units are well maintained. Gianfranco also decided to reassess their autoclave practices, and realised that they were over-sterilising materials like PBS or new tip boxes. As such he was able to reduce the size of the autoclave for the new centre by 50%
To ensure that the new equipment was to be correctly utilised, Gianfranco organised an equipment-training day where product managers all come to the lab and train staff and students on their relevant kit.
Importantly, the new fume cupboards installed in the new centre are all set to ‘low-flow’, which minimises the amount of conditioned air expelled by the laboratory. Such variations on fume cupboard installations will save the building thousands in energy costs annually and help reduce the universities emissions of carbon dioxide.
To reduce the amount of packaging going out through clinical waste streams, Gianfranco has staff and students open packaging outside the laboratory where feasible and ensure it leaves in appropriate waste routes.
Sustainability and efficiency are now integrated into induction materials. This ensures that the good-practice implemented becomes common and will continue into the future.
Such actions are beneficial to the scientists as well as to the estate. They save energy and money, mitigate the environmental impact of the laboratory, but also reduce lag times and improve research quality. Evidence can be seen beyond the reduced procurement costs that while the new facility is smaller than previously, they are currently able to fit more researchers in it. Gianfranco said, “When we first came and saw the shelving and spaces, we were worried about how we would fit. However, since we have conducted the exercise in consolidation and optimisation, we’re able to fit far more than we expected. Everyone seems really happy with it now.”
Fume Cupboard Flow – Saving Energy in Laboratories
Common within many laboratories are fume cupboards, which are large pieces of equipment which safely extract air within a contained small area to ensure worker safety. King’s College London (KCL) is no different in that it contains several hundred of them, albeit only 30 or so are directly under KCL management. This is due to the fact that the majority of KCL’s research spaces exist either within the Trust, or within Bouygues operated spaces (under PFI contracts). Fume cupboards are notorious for consuming large amounts of energy, and can easily consume more than the average UK household uses. That said there are many ways in which this may be mitigated to achieve energy savings, and thus significantly reduce the impact of KCL’s laboratories on the environment. With this in mind, KCL’s Energy team managed a project to achieve exactly that, and targeted the worst offenders under KCL management.
Fume cupboard within KCL managed buildings were surveyed for flow rates, including the Hodgkin building, James Black Centre, the Rayne Institute, and the newly built Wohl. There was a focus on flow rates in particular as it is common for them to creep up over time. Increased flow means more air is exhausted, which the college has likely heated or cooled, resulting in waste energy. As such, surveying existing fume cupboards for excessive flow rates helped highlight which were particularly wasteful. Furthermore, all fume cupboards surveyed were ‘fixed-flow’ or in other words typically on 24/7 with a constant volume of extract. All fume cupboards surveyed were considered for conversion to variable air-volume (VAV), where flow rates are automatically reduced when sashes are lowered and not in use, resulting in significant energy savings. Conversion to VAV is only appropriate for fume cupboards in heavy use and in particular settings, and the surveys revealed only one fume cupboard was appropriate for this within the Rayne building located at Denmark Hill.
12 fume cupboards across King’s were selected for reduction in flow rates, while one designated for conversion to VAV from fixed flow. Flow rates discovered during the survey varied from 40-70% higher than necessary. Coupled with savings due to a heavily-used fume cupboard being converted to VAV, the project had an estimated payback of only 2.5 years. Pictured here is laboratory manager Amanda Wilson of the Rayne, who manages the fume cupboard which was converted to VAV. This conversion was particularly prudent as the Rayne building is undergoing significant ventilation upgrades, and thus an existing VAV systems savings will be compounded. A review of the fume cupboards showed that flow rates had remained low in the year since project completion, putting savings at an estimated £3,800 per year.
Waterless Condensers – Saving Water and Reducing Risk in Laboratories
Chemistry and pharmacy laboratories can consume large amounts of water, typically used for cooling of reactions and equipment. Some of the reactions which utilise water cooling can last hours and even days, meaning tonnes of water will be used and run straight into the drain. Not only does this have an environmental cost, but it can result in damages through flooding and leaks. This very scenario occurred within the Franklin-Wilkins building of King’s College London (KCL), when an overnight condensation reaction using flowing tap water to cool a reaction had a loose pipe. The resulting damage due to the flooding exceeded £10,000.
Simultaneous to this flood, KCL Sustainability had begun investigating a new piece of equipment coming onto the market termed ‘air-condensers’, or ‘waterless condensers’. These would expose contents to a high surface-area of glass in contact with only the air, and would provide sufficient cooling without the running of water to permit condensation within. At the time only two companies had produced such condensers, and a trial was set-up with users from KCL’s Pharmacy & Forensic Science Department. Both units being compared performed well, but users and KCL Sustainability decided on the Asynt version, termed the CondenSyn.
KCL Sustainability funded the purchase of 25 of these units for Chemistry and Pharmacy laboratories where the majority of condensation reactions were taking place. To accompany the new equipment, a user guide was created (pictured upper right), and users were consulted to ensure they understood why they were being purchased and what solvents would work best (not all do). Users were consulted after 6 months of use, and reported back that they found them to be “useful enough that when we broke one or two, we decided to replace them ourselves” according to Simona Blasio (Research Student, Institute of Pharmaceutical Sciences).
Crucially, the new units were found to be effective for the researchers themselves, and simultaneously avoided the need for running tap-water to cool overnight thus reducing the associated risk of flooding. Based on estimates of usage from those using the units, they saved an estimated £3,300 in water costs, or more than 1,500 m3 of water per year. This doesn’t factor the savings due to avoided flooding, so real cost will be even greater.
Sustainable Practice in Pharmaceutical Teaching Labs
Since launching the Sustainability Champions programme in 2013, a variety of phenomenal teams have joined and employed a variety of laudable improvements. One impressive team has been the teaching labs within the Institute of Pharmaceutical Sciences (IPS), based in Franklin Wilkins Building (FWB), Waterloo.
Not limited to the criteria requested by the awards programme, this technical team has gone above and beyond simply achieving sustainable practice within their spaces. They have actively engaged colleagues and students and encouraged them to embrace sustainability in the laboratory setting.
Their achievements in sustainability started in part when their fume cupboards and spaces were to be renovated. Helena Wong, IPS teaching technician at the time, assumed an integral role within the refurbishment team to ensure that the 19 new fume cupboards were both low-flow as well as variable air-volume (VAV), ensuring up to £9,000 in annual energy savings. The Pharmacy team, including Ayesha Naeem, Wendy Lewis and Daniel Asker, now not only ensure that fume cupboard sashes are kept low, but also educate students on why this action is important through posters and stickers designed by the team.
The technical team also practices Green Chemistry, including the reduced use of potentially harmful chemicals within their tutorials. The team uses expired chemicals and reagents after testing for viability. They also constantly try to reduce the volume of chemicals used to the minimum; examples include reducing the volume of mobile phase required. They also convert excess reagents to reagents of use such as 60% ethanol to 70% ethanol for decontamination.
The IPS technical teaching team actions have not only resulted in direct savings for the department and estate, but increased sustainability in the labs. Their teaching practices and inductions extend beyond their facilities, and help prepare King's students and researchers on how to conduct sustainable science wherever they go once their King's journey has concluded.