Energy-efficient thermomixers reduce carbon footprint of experimental evolution

by Athena Lam | Feb 16, 2026 | Environmental Sustainability (ES) | 0 comments

The cost of studying evolution

Experimental evolution is a powerful technique for understanding how organisms adapt to changing environments. By recreating specific conditions in the lab, such as shifts in temperature or acidity, scientists can observe evolutionary processes in real time.

While greatly useful for understanding how the first organisms originated on Earth, this approach comes with challenges. For instance, one of the earliest life forms is thought to be thermophiles, microbes that thrive at extreme temperatures (41 to 122 °C). Mimicking these conditions in the lab requires prolonged high-temperature incubation, which is energy-intensive and costly. Traditional shaking incubators not only consume large amounts of electricity, but also risk being damaged when operated for prolonged periods at high temperatures. Evaporation of culture media adds further complications, potentially affecting the integrity of the experiment.

Thermomixers vs traditional incubators

To tackle these issues, final-year Environmental Sustainability Project (ESP) student Gwyneth Darwent (2022/23) and researchers explored an alternative strategy for growing these microbes: using thermomixers instead of traditional incubators.

While both devices provide a constant temperature for culturing cells and microbes, thermomixers simultaneously provide mixing and are often smaller than shaking incubators.

In their study, the team worked with the archaeon Sulfolobus acidocaldarius, which grows at an optimal temperature of 75 °C. Aside from developing an experimental evolution protocol at high temperatures, they introduced a simple method to compare energy consumption between the two devices:

Unplug the devices from sockets and plug in energy monitoring plugs, initialising them according to manufacturer’s instructions.
Measure energy use over 2 to 24 hours (longer durations give more accurate estimates).
Record and compare the results.

Thermomixers save energy and money

Figure showing energy consumption of traditional incubator (top; red line) and thermomixer (bottom, blue line) at different temperatures over 2 hours. Figure taken from Al-Baqsami et al., 2024.

The study revealed striking results: thermomixers consumed almost 40 times less energy than traditional shaking incubators, while still supporting comparable microbial growth. This makes using them a potential strategy for reducing the carbon footprint of experimental evolution without compromising experimental outcomes.

Beyond sustainability, thermomixers offer practical benefits. Their small size and lower cost make them ideal for labs with limited space or resources. By removing the need for multiple large incubators, researchers can run parallel experiments more efficiently and affordably.

How You Can Take Action

Monitor and reduce energy use

The Faculties of Biology, Medicine and Health (FBMH) and Science and Engineering (FSE) have launched a Plug Energy Meter Campaign to help lab users understand and reduce their energy use. Plug-in energy meters are now available to borrow from several Faculty buildings, enabling lab users to monitor equipment, identify high-consumption hotspots, and make informed changes to reduce their carbon footprint. Find out more about the campaign here: Measuring what matters: plug energy meters for sustainable labs.

Host a similar project

If you are a researcher or academic at the University, you might also consider hosting a final-year Environmental Sustainability Project (ESP) student. ESP students can support you in greening your lab protocols and calculating impact. To express interest, please contact Dr Maggy Fostier, Associate Dean for Environmental Sustainability.