The manufacturing step in the Mobius LCA study highlighted energy use in running the HVAC system in the cleanroom as having a significant global warming potential. As a result, we implemented a unique particle counting and air-handling system that reduced the energy use by 69%.
Most cleanrooms operate with a “set it and forget it” air-handling system and use a tremendous amount of energy to run powerful air-handling fans to support air conditioning and heating system through the HEPA filters installed in the ceiling. In most cases, fans run constantly, whether manufacturing is taking place or not.
To improve upon this, we installed particle counters in cleanroom return air walls to constantly test the space. This allows the fans to slow down automatically when the air meets cleanliness standards. On the weekends, or other times when no products are being manufactured, fan speed is reduced, resulting in significantly energy savings.
We were able to recognize a savings of 141,000 kilowatt hours per year, reducing our annual operating cost by $16,000. Since the system cost about $12,000, this initiative delivered a return on investment in less than one year. We are now considering implementing similar systems in our other cleanrooms.