Cold storage plays a crucial role in research by preserving reagents and biological samples. But its environmental footprint is a persistent challenge: ultra-low temperature (ULT) freezers are among the most energy-intensive equipment in the laboratories, consuming as much electricity as an average household.[1] Also, they often rely on refrigerants with high global warming potential.
As sustainability becomes a higher priority for research institutions, improving freezer efficiency is essential. This article explores practical strategies, best practices, and the importance of preventive maintenance to help laboratories optimize cold storage management, achieve their sustainability goals, and cut operational costs.
Small steps, big impact: Why you should never skip preventive maintenance
Preventive maintenance is essential to improve freezer efficiency and help extend the lifespan of the freezer. It can also be a key factor that helps to meet manufacturer warranty. However, it is often overlooked. To avoid irreparable damages, additional costs, and the loss of precious research samples, laboratories should follow proper freezer maintenance procedures. These activities are typically performed annually, semi-annually, or quarterly. Regular servicing and routine inspections help to detect potential issues before they escalate.
Routine temperature monitoring is essential for detecting irregularities early and helps maintain a stable and safe environment for stored samples.
One of the most effective approaches to maintaining cold storage efficiency is defrosting. Depending on the freezer conditions, usage frequency, and internal regulations, this should be done at least once a year. Ice buildup makes the compressor work harder to maintain temperature stability, resulting in increased energy consumption. It can also cause damage to the inner doors or stop them from fully closing.
Another good practice is to scrape frost and ice off doors and the inner chamber regularly. Freezer door gaskets should be brushed and wiped down with a soft cloth to be kept free of ice. It is important to use appropriate ice scrapers and brushes to avoid damage. Moreover, door gaskets need to be checked for cracks and tears to prevent cold air leaks.
Similarly, cleaning air filters and condenser coils improves airflow and cooling efficiency. To reduce the risk of overheating, dust and dirt buildup should be removed with a vacuum. Areas with lower air quality require more frequent cleaning and filter changing to prevent clogging and inefficiency.
Routine temperature monitoring is essential for detecting irregularities early and helps maintain a stable and safe environment for stored samples. Creating a maintenance log and schedule is an effective way to keep equipment running smoothly and prevent costly breakdowns. It’s also helpful to invest in a remote monitoring solution that can alert you of issues even when no one is present at the lab by sending a text message, email, or other notification. Even if your freezer doesn’t offer remote monitoring by default, it may support third-party sensors that offer the same functionality.
Freezer organization: The key to efficiency and sustainability
Proper freezer organization is essential not only for maintaining efficiency and sample integrity but also for reducing energy consumption and extending equipment lifespan. One of the best practices is using storage racks and boxes to maximize space while keeping samples easily accessible.
Implementing a standardized labeling system will further enhance organization and prevent samples from misidentification and loss. For proper cataloging, each sample should have necessary details such as the name, date, owner, and project. Using fridge-safe labels and pens ensures that information remains intact over time and won’t fade or smudge.
A solid inventory management system is crucial for maintaining a well-organized, efficient, and sustainable lab. The key to success lies in consistency, regular updates, and teamwork. Without a structured approach and engagement of all the group members, samples and reagents can become misplaced, lost, or forgotten. This can lead to unnecessary purchasing, wasted resources, and inefficient use of space.
Conducting periodic audits and removing outdated or unneeded probes help improve organization. Furthermore, posting a storage plan on the door of the freezer provides an easy reference and allows users to quickly locate samples, reducing door opening time, minimizing temperature fluctuations, and optimizing energy use.
A solid inventory management system is crucial for maintaining a well-organized, efficient, and sustainable lab.
The power of daily habits for greener cold storage
Alongside proactive maintenance and strategic inventory management, there are several other steps labs can take to boost their ULT freezer efficiency:
- Place the most frequently used samples at the front of the freezer to minimize open door times
- Regularly audit and remove unused or expired samples
- Fill empty space with boxes to maintain airflow, ensuring temperature stability and curbing frost buildup
- Share freezer space with other teams
- Report any irregularities in performance, such as temperature fluctuations, or appearance, like cracks in door gaskets, immediately
My Green Lab International Freezer Challenge
Interested in taking your cold storage sustainability a step further? To encourage more environmentally conscious freezer usage, lab sustainability non-profit My Green Lab hosts the International Laboratory Freezer Challenge every year.2 This friendly competition further incentivizes labs to revamp their cold storage practices and proactively seek ways to cut the environmental footprint of their freezers.
Take action today and improve your cold storage
Sustainability in cold storage requires a proactive approach that combines preventive maintenance, smart organization, energy-efficient practices, and teamwork. Regular cleaning, defrosting, and updated inventory management systems are essential for improving cold storage efficiency without compromising the integrity of samples. By adopting best practices, laboratories can reduce their carbon footprint, optimize storage use, and lower energy consumption and costs. This strategy not only supports research operations and productivity but also fosters a more sustainable and safe working environment.
References
- Gumapas, Leo Angelo M., and Glenn Simons. "Factors affecting the performance, energy consumption, and carbon footprint for ultra low temperature freezers: case study at the National Institutes of Health." World Review of Science, Technology and Sustainable Development 10, no. 1-2-3 (2013): 129-141.
https://doi.org/10.1504/WRSTSD.2013.050786 - https://www.mygreenlab.org/freezer-challenge.html
