University of Colorado Boulder
IN-2: Innovation 2

Two innovative practices implemented in CU Boulder research laboratories have been developed by the CU Green Labs Program in cooperation with the researchers themselves and related campus units. Together they are part of an array of innovative practices pioneered by the CU Green Labs Program, a partnership between CU Facilities Management and the CU Environmental Center. The innovative program activities included in this credit are: 1) ETHANOL REUSE: Re-Use of Cold Trap Ethanol to Sterilize Cell Culture BioSafety Cabinets. The Stable Isotope Lab at the Institute for Alpine and Arctic Research (INSTAAR) uses ethanol cold traps during its analysis of ice core samples. Over time, water from the air humidifies the ethanol. As the water concentration increases in the ethanol solution, ice crystals begin to form in the cold trap rendering the solution useless to the lab. Because of the strong interaction between ethanol and water, distilling the used ethanol is energy intense and does not remove sufficient water from the ethanol to be of real benefit to the lab. Since this diluted ethanol is clean, the lab wanted to know if there was a way in which the ethanol could be re-used instead of having to discard the ethanol as hazardous waste which they did for many, many years. At a meeting between Environmental Health and Safety (EH&S) and the CU Green Labs Program, the group developed the idea of re-using the ethanol at the Biochemistry Cell Culture Facility. In cell culture, ethanol is readily used to sterilize biosafety cabinets and other items, but it is first diluted down with water to 70% ethanol. Since the ethanol leaving the cold traps was on the order of ~85-90% ethanol, it could easily be diluted to 70% ethanol for re-use in cell culture. 2) ELECTRON MICROSCOPE POWER DOWN PRACTICE: Turning off a Scanning Electron Microscope (SEM) When Not in Use for Significant Energy and Water Savings. Electron microscopes require vacuum conditions to be maintained for instrument integrity and performance. As a result, electron microscopes, their vacuum pumps, and associated chillers remain on 24 hours a day, 7 days a week. Some instruments do come with a standby mode that enables the high vacuum pumps and associated chillers to be shut off, leaving some microscope components on such as the low vacuum pumps on, but most scope facilities choose not to use the standby mode because they are concerned it will affect the performance of their instruments. Some electron microscopes do not come with standby mode option at all, including a scanning electron microscope in the Ecology and Evolutionary Biology (EBio) Department at CU-Boulder. This scope is infrequently used by the department but is an instrument which the department wishes to keep. The scope and the chiller use ~78 kWh/day in electricity and likely on the order of ~500 gallons/day of tap water when left on all the time (processed chilled water is not available in that building). A lab member who was bothered by the constant sound of the tap water going down the drain asked whether this equipment could be turned off when not in use since it was infrequently used by the department. CU-Boulder Green Labs reached out to the manufacturer, JEOL, to see what was possible. The request was an unusual one for JEOL, but JEOL was open to the idea. They reported that while most electron microscopes cannot be turned off regularly, this particular model could as long as the scope was turned back on at least every two weeks to maintain the vacuum in the chamber of the instrument.

ETHANOL REUSE 1) Ethanol re-use has been in effect now at CU-Boulder for 1. 5 years with ~120 gallons of ethanol/year being diverted from hazardous waste and being re-used in Biochemistry cell culture, saving the cell culture facility ~$1500/yr in avoided ethanol purchasing costs. The ethanol is transported between the two INSTAAR & Biochemistry Cell Culture labs by CU-Boulder EH&S. ELECTRON MICROSCOPE POWER DOWN PRACTICE 2) For no more than two years now, the Stock Lab in EBio has been keeping this instrument off when not in use and making sure it was turned back on briefly at least every two weeks to maintain vacuum in the instrument chamber. It is avoiding an estimated ~28,000 kWh/year in electricity use and ~180,000 gallons/year in tap water use. Considering that putting electron microscopes in standby mode is uncommon for those instruments that have that option, turning an entire electron microscope completely off when not in use is an exceptional act that is simply not done in this field of work to the best of our knowledge.

As required by STARS, both innovations reported above are supported by letters of affirmation from experts in the field. As the STARS Reporting Tool only has capacity for one letter of affirmation and two experts were relevant to the unique aspects of each innovation, their separate letters have been combined into one document file and uploaded above.