ULT freezers: Beyond the specifications

Ultra-low temperature (ULT) freezers are an essential tool in labs for preserving critical biological samples at temperatures as low as -80°C. But to achieve this, an average ULT freezer can consume as much energy as a family home – around 20 kWh per day.

This makes ULT freezers among the most energy-intensive pieces of equipment in any lab, making them a high-priority target for lab managers starting their journey to a more sustainable lab. This has also led manufacturers to invest heavily in R&D to improve the performance and efficiency of these products.

Digging deeper on ULT freezers: 5 questions to ask

For labs looking to replace end-of-life ULT freezers, assessing the product features and specifications is one part of the process. But what other questions should lab managers be asking?

1. How energy efficient is it, and according to who?

External certifications and comparison tools are essential reading materials. For example, the Thermo Scientific TSX Universal ULT series is ENERGY STAR® certified, using up to 33% less energy than typical ULT freezers. Thermo Fisher’s V-Drive technology drives this efficiency by optimizing power use based on workload, reducing energy consumption and operational costs. This high efficiency helps labs save on energy bills while supporting broader sustainability goals. Check out the Green Fact Sheet for more details.

Additionally, each TSX Universal ULT freezer carries an ACT label from My Green Lab, offering clear, third-party verified data on environmental sustainability. With best-in-class scores in multiple sustainability categories, the ACT label provides labs with transparency about the product’s impact, helping lab managers make more informed, eco-conscious decisions.

2. Is the product just meeting minimum standards, or does it exceed expectations?

Our freezers use refrigerants with low GWP and low-impact insulation, ensuring zero ozone-depleting potential. Their design complies with EU regulations on F-gas emissions years ahead of mandated deadlines, positioning them as eco-conscious choices in lab environments.

3. Where is it made and how?

The Asheville, North Carolina facility, where Thermo Fisher produces the Thermo Scientific TSX ULT freezers, is a zero-waste site that diverts over 90% of waste from landfill. Additionally, the facility uses components like stainless steel and aluminium made with up to 70% recycled content. This commitment to waste reduction supports labs aiming to align their operations with circular economy principles.

4. Is it built to last?

With a 12-year warranty, TSX freezers are designed to outlast most alternatives by several years, minimising the frequency of new unit production, transport, and disposal. A longer lifespan means less environmental impact from manufacturing and end-of-life processes, as fewer freezers need replacing.

5. How sustainable is the packaging?

Thermo Fisher also designs sustainability into product packaging. We pack our freezers using recycled corrugated cardboard and foam planks, reducing the environmental impact of packaging waste.

How are your ULTs being used?

Once a product is selected, there are a range of simple steps that lab managers can take to further minimise the impact of their ULT freezer usage. These include:

• Proper placement and maintenance: Positioning ULT freezers in well-ventilated spaces and performing regular maintenance, such as cleaning condenser coils, can enhance their efficiency, reducing energy use over time.

• Sample organisation and inventory control: Efficient sample management allows lab personnel to quickly access items, minimising the frequency and duration of door openings. This practice conserves energy by maintaining internal temperatures and reducing the workload on the freezer’s cooling system.

• Adjusting temperature set points: Studies have shown that, depending on sample requirements, setting ULT freezers to -70°C instead of -80°C can significantly lower energy consumption by up to 30% while still preserving sample quality.

• Recycling and disposal programs: At the end of their lifecycle, some ULT freezers can qualify for recycling programs. In the case of Thermo Fisher’s TSX Universal ULT freezers, for example, Thermo Fisher can facilitate the proper disposal of older units, supporting lab managers in achieving waste reduction goals.

By evaluating more than specifications in your product decisions and continuing to adopt and build upon sustainable habits, labs can move towards reducing their environmental footprint without compromising the safety of their samples.

Watch our webinar on demystifying the challenges with cold storage where our inhouse experts discuss the challenges faced by labs when it comes to cold storage.

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