Energy Savings Calculation:

Maximum flow of hoods: 850CFM

Min flow of hoods:300CFM

Electricity savings from lowering fume hood sashes: total 15% or ~$123,000/yr (nighttime 8.5% reduction;daytime 6.5% reduction)

Steam consumption savings from lowering fume hood sashes: 17% or ~$106,000/yr

Chilled water consumption savings from lowering fume hood sashes: 20% or ~ $127,000

Single fume hood energy use:

Exhaust for single fume hood:

127mBTU/yr costing MIT $1000 for steam and $1200 for chilled water

Compare with:

Single family home av. 115mBTU/yr for heating and cooling

Some Calculation Asssumptions*:

0.75 heat exchanger efficiency

FY 2005 FY 2006 (projected) cost per
Chilled Water $0.23 / Ton-hours
Electricity $0.115 / Kilowatt-hours
Steam $14.30 / 1000 pounds

*for exact calculations and further assumptions see Steve Amanti's Undergraduate Senior Thesis