Promoting sustainability and addressing climate change can feel overwhelming as an individual or small group. But small steps can lead to big changes, and sometimes all we need is a little guidance.
With Earth Day right around the corner, MyHMS checked in with Colette Baker, sustainability manager at Harvard Medical School, to discuss the Green Labs initiative — a program to support laboratories in reducing their environmental impact — and how small changes can help HMS meet its sustainability goals.
MyHMS: Why are laboratories such a focus of sustainability efforts at HMS?
Colette Baker: Labs are fundamental to the research mission of HMS. They’re also some of the most resource-intensive spaces we operate. At HMS, labs make up about 65 percent of the space on campus but account for about 80 percent of our total energy use, and they use more than twice the water per square foot compared to non-lab spaces. Even small changes across many labs can add up to a meaningful impact — on emissions, efficiency, and costs.
MyHMS: Why do labs consume so much energy?
Baker: Labs’ design makes them energy intensive. They often require 100 percent outside air ventilation, precise environmental controls, and specialized equipment that may run 24/7. Labs rarely fully “power down.”
Fume hoods are a common major driver. An open fume hood acts like a fan blowing heated or cooled air out a window all day, and the building’s HVAC has to work constantly to replace that air. One hood can use as much energy as 3.5 homes in a year, and we have more than 200 of them on campus.
MyHMS: What is the mission of the Green Labs initiative?
Baker: It is to help research labs reduce their environmental impact while maintaining the safety and integrity of their work. It’s about making sustainability practical and achievable through small changes that support efficiency and reduce waste while aligning with how labs function.
MyHMS: What’s the Green Lab certification process like?
Baker: Certification starts with a checklist that covers sustainability practices across energy, equipment, waste, water, and purchasing. It includes a mix of required and optional actions. Some are simple, like shutting a fume hood sash or posting signage. Others go a bit further, like adjusting freezer temperatures or setting up an equipment shutdown checklist.
We know not everything is within a lab’s control. The goal isn’t to check every box but to help labs make meaningful progress where possible.
MyHMS: What stands out, from a sustainability perspective, when you visit labs?
Baker: Small things add up. Energy can be wasted without anyone realizing. I often see equipment running 24/7, even when it’s not being used. Sometimes it’s just habit, or no one’s quite sure who manages it.
There is equipment that does need to run constantly, such as ultra-low temperature freezers, but even those have opportunities for increased efficiency. I’ve had a lot of conversations about the -80°C default setting for these freezers. A single freezer can use as much electricity as a household, and we have over 250 of these on campus. Switching to -70°C, or “chilling up,” can reduce energy use by up to 40 percent, lower the risk of compressor failure, and extend the life of the unit. Most samples have been shown to be stable and safe at -70°C; in fact, that used to be the standard before -80°C models became available.
We have a growing number of labs making that temperature change and encouraging others to do the same. None of these issues or adjustments are huge on their own, but when you multiply them across campus, they represent a real opportunity to reduce waste and improve efficiency without disrupting the science.
MyHMS: What are simple steps labs can take to minimize their impact?
Baker: Start a conversation at your next lab meeting. “What’s running 24/7 that doesn’t need to be?” or “What could we do differently that wouldn’t disrupt our work?” That alone is often enough to get things moving.
And if your lab is feeling cluttered or chaotic, a full lab or freezer cleanout can make a huge difference. It’s not low-effort, but it is deeply worthwhile. Schedule a day, buy lunch, and get it done. It reduces stress, makes the space feel better, and usually uncovers a few unexpected sustainability wins along the way.
MyHMS: What feedback have you had from labs that have been certified as Green Labs
Baker: Feedback has been really positive. Several teams told us they were surprised by how many sustainable practices they were already doing or how helpful it was to see it all laid out.
People on campus care deeply about reducing the environmental impact of research, but it can feel overwhelming. Certification is meant to provide a structure to do so — not more work, just a way in.
If you’re interested in joining the Green Labs initiative, email sustainability@hms.harvard.edu or visit the sustainability website.
This conversation was edited for length and clarity.
