Chemical fume hoods and sterile cabinets
Chemical fume hoods and sterile cabinets, LAF benches, are among the most energy intensive equipment in a laboratory environment.
At SDU, we have 550 fume hoods in the labs. A single fume hood can use as much energy as a household due to the large volume of air that must be moved through the hood by the ventilation system and the possible heat loss in the process.
Closing sashes on the fume hoods when they are not in use saves an enormous amount of energy since the ventilation must increase when a sash is up. Hence, significant savings can be achieved by keeping the sash closed when the fume hood are not in use or switch off the fume hood.
Switch off fume hood project
At SDU, we are working on a “switch off the fume hood project”. Currently, all fume hoods are running round-the-clock. We explored that around half of our fume hoods could be turned off at nighttime (outside working hours), and some also during the daytime as they are not necessarily in use. A single fume hood has at least a standby energy use compared to 1/6 of a household. At SDU we have 500 fume hoods, consequently, a potential for a large energy saving.
Hence, to save energy, we want to switch off the fume hoods whenever possible without jeopardizing the safety. However, this is not easily done as the ventilation of the room has to be adjusted when reducing the airflow through the fume hoods. In addition, we must change the safety instructions and working habits.