Tuesday, August 01, 2006

A Certified Energy (Death) Star Appliance

Dylan writes about a reply he received from the campus energy manager at his school (ssssss) in response to his query: does a fume hood in a laboratory really use up more energy than an entire house? Well, it does.

Yes, it is true that a single fume hood uses as much energy as a whole house. The key word is 'energy'’ since it is not just the electricity to run the exhaust fan (which is significant) but also all of the energy that went into cooling and heating the air that gets sent out the stack. None of that air can be recirculated as it would be in an office building since it might be contaminated with dangerous chemicals.


She went on to quote some actual monetary figures, and even sent me Lokey'’s power bill for the month of June. I will not reproduce those details here but suffice is to say it was an astonishing amount of money, about 7x more than a similar sized hood-free building. For the rest of the day I felt the pang of self-guilt that comes from being associated with such an energy-hungry association. The grand total aside, I was informed that each fume hood costs ~$5,000/year (~$420/month) to operate.

Self-guilt is right. Five-frickin'-thousand a year, Lobster Scientistfor one lousy fume hood? For those not in the know, fume hoods are simply exhaust fans placed on top of benches where scientists can safely work with hazardous/volatile chemicals, as pictured to the right, behind the, uhm, lobster scientist.

In my lab, on the 8th floor of Latimer Hall, there are roughly 40 of these energy death star fume hoods, amounting to a $200000+ yearly fee just to keep these suckers running all day long, and that's only for our floor. These, along with the building's ventilation system, are important to feed the rooms with a constant negative air pressure, meaning that air is constantly sucked out of the rooms through exhaust vents, allowing for quick removal of any toxic/smelly fumes that may permeate the lab from chemicals/graduate students. This importance precedes the exorbitant energy usage they require, yes, but are there any ways to reduce this expenditure and are we pushing for this to happen? Of course.

The Lawrence Berkeley National Laboratory (LBNL) actually is at the forefront of new hood technologies. Aptly titled the Berkeley Hood (hold your puns), it utilizes separate fans near the front of the bench to assist in removing vapor contaminants, and allows for a significantly decreased rate of air flow from the exhaust; you can see it visually with this nifty flash animation.

Tests have shown (and a more interesting movie clip) that this new technology is just as effective as standard energy-whoring hoods, and LBNL estimates that the air flow savings in 'da Hood will conserve 75% more energy. Always at the pinnacle of scientific excellence, Berkeley is also well-known by another phrase: treading knee-deep in bureaucracy.

See, the Berkeley Hood was created way back at the turn of the millennium, and possibly earlier (the earliest article I could find was in 2001), but only recently has seen some success in procuring the Go Ahead for new field tests. As it turns out, the California Occupational Safety and Health program (Cal/OSHA), an enforcer of California laws and regulations related to workplace safety and health, also regulates laboratories for safe practices and equipment, including fume hoods. Cal/OSHA adopted a standard over 30 years ago that proclaimed an air flow of 100-feet-per-second as the minimum rate a hood can be operated at. Even in the face of new technologies that could safely lower that air flow considerably, Cal/OSHA is reluctant to change precedent: researchers were asking to perform field tests with the Berkeley hood back in 2002, and just this year have been approved to begin.

In the midst of all of this Berkeley-esqe pseudo-progress, it is recommended that we simply close our hoods to decrease the air flow. Maybe we should just give up and patent that.

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