How to reduce energy use in your laboratory:
3) Shut it down
This article is from The Scientist: http://the-scientist.com/2011/07/01/how-green-is-my-lab/ It talks about Harvard's experience with measuring energy use in laboratories. UVM labs have a similar profile of high energy use.
At Harvard University, laboratories account for 21 percent of the 26 million-odd square feet of university real estate. Yet the labs consume 48 percent of the energy, says Jamie Bemis, the Faculty of Arts and Sciences Green Program Coordinator at Harvard’s Office for Sustainability. “It’s a very energy-intensive space,” Bemis says—not to mention one that uses vast quantities of water and generates mountains of waste.
This situation is not unique to Harvard, of course. According to an essay by sustainability experts at the University of Texas at Austin, “Research laboratories are often the largest consumer of utilities at a research university.” Across the country, universities—motivated by a desire to be better global citizens, as well as to improve their bottom line—have established offices and undertaken efforts to help reduce the environmental “footprint” of laboratory spaces. Many of these efforts are large-scale projects beyond the reach of individual researchers, such as smart building redesigns and campus-wide initiatives. But there’s still plenty an environmentally conscious researcher can do.
The Scientist spoke with sustainability experts at different universities to bring you their tips for creating a more environmentally friendly lab. Here’s what they said.
If there’s one tip every sustainability manager hammered home, it was this: close the sashes of unused chemical fume hoods. “A fume hood uses the equivalent of three residential houses’ worth of electricity per year,” says Amorette Getty, co-supervisor of the LabRATS program at the University of California, Santa Barbara. That’s because whenever a fume hood is open, it pulls conditioned room air through the sash and into the hood. Fresh outside air then has to be reconditioned and pumped back into the room. Most labs already require at least six air changes per hour; an open hood can increase that number significantly, Getty says. “If you develop the habit of closing the sash, you can save up to $2,000 to $3,000 per year per hood.”
Most researchers never benefit directly from those savings, of course, because they neither see nor pay their own electric bills. But for a university, the savings can add up. Lauren Olson, project coordinator in Michigan State University’s Office of Campus Sustainability, estimates her campus chemistry building’s annual energy tab is $1.2 million. “We can get that down to about $700,000 if everyone kept the hoods open for just half a day,” she says.
Campus sustainability teams at UCSB and UC Davis have devised a simple but apparently effective visual reminder: a sticker, placed on the side of the hood, featuring a color gradient from red to green that reflects energy usage at different sash heights. “In some labs, we’ve seen a complete change in behavior when we install the stickers,” Getty says. “It’s very gratifying.”
The most energy-intensive pieces of equipment in most biology labs, says Bemis, are ultra-low temperature (−80°C) freezers. A typical unit consumes between 16 and 35 kWh/day, and Harvard’s College of Arts and Sciences, School of Public Health, and Medical School, collectively, run hundreds of them 24/7.
Actually, Getty says, freezers deliver a double environmental negative: not only are they voracious energy users, they also pump out excessive heat. The common practice of grouping freezers together in a single room is a good idea if supplemental cooling is available. But it can potentially throw off an entire building’s climate control as its air conditioners labor overtime to keep that one room cool. “We call that a ‘tail wagger,’” she says, “one room that influences how the whole system works.”
Getty and others recommend some simple, commonsense measures: (1) Defrost regularly and ensure that rubber door gaskets provide a good seal; (2) discard outdated and unneeded samples; (3) consolidate sample boxes within and among labs to reduce the total number of running freezers; (4) maintain an up-to-date inventory for each freezer; and (5) only store at −80°C those samples that actually need to be at that temperature. DNA in solution can safely be stored at –20°, notes University of California, Davis, sustainability manager Allen Doyle. “DNA is a robust polymer; some researchers have their entire collections at –20.” For archival purposes DNA may also be kept indefinitely using Room Temperature Sample Storage (RTSS), a powder pre-aliquoted in microtiter plates that is mixed with a DNA extract and then dried at room temperature, says Doyle. Storing DNA in this way frees up freezer space, reduces the number of samples at risk when power outages occur, and ultimately, lowers cost.
In May, universities nationwide participated in Freezer Challenge, a competition in which labs could earn points by employing RTSS, cleaning out their freezers, inventorying the contents, “retiring or decommissioning” freezers, and “chilling up”—raising units’ set points by at least 10°C.
That last action, says Doyle, can make a significant energy difference: a 10°C elevation saves the equivalent energy of one standard freezer, and recent data show that a freezer reset from −86°C to −60°C uses half as much energy.
You wouldn’t leave your lights at home on all night, so why do it in a lab? For that matter, why leave unused drying ovens, vacuum pumps, heat blocks, and water baths running? Each of these consumes electricity even when not in active use, as do computers, microscopes, and pH meters. The green thing to do, according to sustainability managers, is to put as much equipment as possible on timers that switch power off at night.
When left idle at 4°C, refrigerated floor centrifuges use the same energy as a pair of flat-screen televisions, says Kathryn Ramirez-Aguilar, Green Labs Program Manager at the University of Colorado, Boulder. “It’s worth turning those off when they’re not in use”—a practice that not only is environmentally sound but also increases the lifespan of the equipment, she adds.
Of course, every lab is different, and what works for one may not translate to another. At Colorado, Ramirez-Aguilar encourages each lab to appoint an “eco-leader,” a volunteer who essentially acts as environmental point person. “What’s powerful about a lab eco-leader is they know the lab and what is and what is not possible in the lab,” she says. Importantly, she adds, eco-leaders “also help engage members of their labs in conservation and identifying conservation projects.”
Thanks to lab members in one particular lab, her office became aware of 11 diffusion pumps used to generate ultra-low pressure conditions that were kept running constantly even when not needed. By putting just five of the pumps onto timers for nightly and weekend shut-off, Ramirez-Aguilar says, the university is saving some 58,000 kWh of electricity and one million gallons of water per year.
Another way to improve a lab’s green grade is to consider where your water comes from, and where it goes. “Deionized water comes out of a tap, but it isn’t free,” says Getty, “it requires a huge investment of time, energy, and water to make it.” So, rather than running the DI water continuously, consider multiple batch rinses instead, says Doyle.
Many labs use aspirators driven by water flowing from a tap to pull a vacuum, for instance in a cell-culture hood. “If you do that for several hours, you end up wasting quite a lot of water,” says Evan Beach, a program manager at Yale University’s Center for Green Chemistry and Green Engineering. He recommends switching to small electric pumps instead.
Similarly, chemists who use condensation towers and rotovaps may run water for hours during distillations and drying processes. That water may flow at a gallon per minute; in 24 hours, that’s over 1,000 gallons wasted. Instead, Beach says, use a pump to recirculate water from a bucket, recycling the same one gallon over and over.
Chemicals can also impact the environment, both in terms of the processes used to create them and those used to dispose of them. MIT’s Environment, Health and Safety Office, working in collaboration with the Chemistry Department under the auspices of EPA’s People, Prosperity, and the Planet (P3) grant program, has developed a Green Chemical Alternatives Purchasing Wizard database to help researchers identify “greener” chemicals for a variety of chemical and biological processes.
One classic example is the DNA gel dye ethidium bromide. A mutagen, ethidium bromide is both hazardous to users and a waste disposal problem. MIT’s wizard suggests researchers try Life Technologies’ SYBR Safe instead. On the plus side, SYBR Safe is, well, safer than ethidium, and approved in Massachusetts for disposal down the drain; on the downside it also is more expensive.
But, notes Susan Leite, EHS officer at MIT and part of the wizard’s design team, there’s more to the cost of a chemical than its price. “There’s the life cycle,” she says, which includes the cost to produce, handle, and dispose of it. “It’s a balance,” Leite says. Some replacement chemicals have their own EHS issues—such as toluene, a suggested alternative to benzene. And some can be used in smaller volumes, while others require more. “We are trying not to shift risks from one area to another,” she explains.
The next time you need to order a chemical, make sure you don’t already have it. That sounds obvious, but nearly every lab has had the experience of ordering things they don’t really need. Likewise, don’t over-order chemicals—they’ll just end up being thrown away.
Dennis Nolan, Assistant Director of Environmental Health and Safety at the University of Texas at Austin, suggests researchers maintain an inventory database of chemicals and supplies, and consider sharing and/or integrating those databases between labs or departments. Such a practice can save researchers money by reducing the number of chemicals that need to be purchased; but it also reduces the amount of material that ultimately enters the waste stream, says Doug Zalla, global director of private label at Fisher Scientific, part of Thermo Fisher Scientific.
Beach’s Yale lab, for instance, uses an inventory system called IHS Dolphin Comply Plus. On request, Beach can search the database to let colleagues (whether in the lab or outside of it) know if a particular chemical is available. “We have a couple times per year where we take a day off and take a snapshot of the lab,” Beach says. “That’s a small price to pay for knowing what you have around.”
Many companies now offer green or energy-efficient lab products. Fisher Scientific, for instance, allows customers to filter its catalog for green products such as environmentally conscious molecular biology kits, recyclable plastics, and energy-efficient instruments. But more than that, consumers can also choose to buy from companies that employ sustainable practices of their own. Fisher Scientific, Zalla says, uses sustainable materials in its packaging and was awarded an Energy Star certification in 2009 for one of its major warehouses “that puts it in the top 25 percent of all buildings in the US in energy efficiency.”
Closer to home, researchers can band together and take such steps as setting common days for consolidated ordering (to reduce shipping costs and waste) and establishing “freezer” (or “closet”) programs (in which a company maintains a supply closet or freezer in the department, and researchers pay when they remove materials for their lab’s use).
Finally, talk to your sustainability office, ask them to perform a sustainability audit, and take an active role in reducing your lab’s environmental footprint. And don’t be afraid to speak out. “When you notice one thing that’s not quite right, you can fix it in your lab, your building, and even on the campus,” says Doyle. “You may have someone like me on campus, who can make it universal. So take one thing and follow through with it.”