Simple changes bring big energy savings to labs without risking the science
The humming motors, flashing lights and heat give any scientist an idea of how much energy a lab uses, but it’s just a general feeling that it’s a lot. In 2015, Moira Hafer, a sustainability analyst at Stanford University in California, reported that lab equipment used more electricity—50% of the total—than any other type of equipment on the campus.1 That makes lab equipment a key target in saving energy.
Science labs require equipment—often lots of it—and each instrument might create an opportunity to save energy. (Photograph by Michael Marsland, courtesy of Yale University.)For a rule of thumb, Allison Paradise, executive director at My Green Lab (Los Gatos, Calif.), says, “Anything with a heating or cooling element or anything that maintains a vacuum is a good candidate for being turned off when not in use.”
The experts interviewed here give their top tips for making your lab run as energy efficiently as possible, just by turning equipment settings down or off.
Timing Matters
“Benchtop equipment in labs is left on nearly 24/7 so it will be ready just in case the researcher needs to use it,” says Star Scott, green lab program coordinator at the University of Georgia in Athens (UGA). Sometimes it takes longer than desired to get a piece of equipment ready to use after being turned off. “For example, it can take an hour or longer for a water bath to reach a desired temperature,” Scott explains. “In research, you cannot wait an hour to continue your process.”
That lag time can be resolved with timers that keep devices ready to use when needed and turned off at other times. Scott explains that timers for benchtop devices “will power the units down at the end of the day, and power them up early in the morning, so they will be ready when the researcher needs it.” Scott adds, “This is a helpful and realistic way to reduce energy consumption in the labs.”
The most energy-efficient approach depends on the lab. Although Quentin Gilly, green labs program senior coordinator, Harvard Office for Sustainability (Cambridge, Mass.), also endorses the use of timers, he says, “These opportunities are more difficult to explore in labs that have scientists working around the clock.”
Freezing electricity usage
Simple and inexpensive methods, like a sticker on hood sashes, can make big energy improvements in a lab. (Image courtesy of the U.S. Department of Energy.)Everyone interviewed for this article pointed to freezers as potential energy-saving options. That’s no surprise given that Hafer’s report showed that these devices consume almost one-third of the electricity used by all of the lab equipment at Stanford. Other sources also show freezers using the most energy of all lab equipment.2
When asked what devices in a lab can be turned down without affecting performance and save the most energy, Paradise says, “There has been a movement to adjust the setpoint of ultra-low temperature freezers—a.k.a. ‘minus 80s’—from –80 °C to –70 °C.” She adds, “My Green Lab uses the slogan ‘–70 is the new –80’ to remind people that changing the setpoint on their freezer can save 2 to 5 kilowatt-hours per day, or reduce the energy consumption by 20%.”
Although Paradise notes that there’s not a lot of data that demonstrate the safety of samples stored at –70, she says, “It’s also hard to find data demonstrating that –80 °C is a better storage temperature.” Paradise adds, “The University of Colorado, Boulder, has about 50% of its ultra-low temperature freezers set to –70 °C, and they have been maintaining a comprehensive database of samples stored at that temperature for many years.”
Before turning down an ultra-low temperature freezer, make sure that your specimens will be safe at that higher temperature. As Scott says, “Most research samples are protected and safe at –70 degrees, but some serum samples are the exception.”
Making the change to a higher temperature can go beyond the science and savings. “This also requires a culture change within the labs,” Ellen Sweet, laboratory ventilation specialist at Cornell University (Ithaca, N.Y.), explains. “The idea that it is better to store samples at the lowest possible temperature is not always true and is costing the institutions that support the labs more money than the lab occupants realize.” Sweet adds, “This culture change should also include the mentality that some of what is being stored should be in the landfill. If regular cleanouts of ultra-low freezers were to occur, some of these freezers could be shut off.”
Labs can also save electricity on thermal cyclers. Gilly says, “If possible, set the equipment to hold at room temperature when finished, or take your samples out when the cycle is finished.”
Turn off
For some equipment, it can just be turned off when not in use. In Hafer’s report about Stanford’s lab, incubators consumed almost one-quarter of the electricity; they should be shut off when not in use.
Lights should also be turned out when not needed. For microscope illumination, says Paradise, “If you have a metal halide light source, turning it off could save 2 to 3 kilowatt-hours per day, but if you have an LED light source, turning it off can save as much as 3 kilowatt-hours per day or as little as less than1 kilowatt-hours per day, depending on the light source and how long it is being used.” She adds, “So the push to turn off equipment is rooted as much in common sense as it is in a drive to save money.”
It makes even more sense to turn other lights off, especially the UV lights used to decontaminate biosafety cabinets. “These can often times be left on for hours, or overnight, in the hopes of creating a more sterile environment,” Gilly says. “In reality, UV decontamination is unreliable, and the bulbs typically have a half-life of under 100 hours.” He adds, “It is best to close the cabinets and turn them off when not in use, and wipe them down thoroughly with 70% ethanol before and after each use.”
Ultimately, any changes “must make it easy for the researchers to be sustainable,” Scott says. “Sustainability is not black or white, and we’ve got to take steps into the grey area and find compromises that satisfy both the researcher and our sustainability initiatives.”
References
- Hafer, M. Inventorying plug load equipment and assessing plug load reduction solutions on a university campus. 2015. Available at: http://sustainable.stanford.edu/sites/default/files/resource-attachments/Plug%20Load%20White%20Paper%20FINAL.pdf
- Market assessment of energy efficiency opportunities in laboratories. 2015. Available at: http://www.etcc-ca.com/sites/default/files/reports/ceel_market_assessment_et14pge7591.pdf