ULT Freezer Energy Use Comparison
Ultra Low Temperature (ULT) Freezers are used for long term storage of biological samples like DNA, RNA, proteins, cell extracts, or reagents. These ULT freezers can be found in molecular biology and life science laboratories across the campus. These ULTs must Cool down to -80 Degrees Celsius in order to keep samples safe. Older make and model ULTs can use as much electricity as an entire house. Many research institutions like ours have large portfolios of older freezers, storing samples tied to research that started 10-20 years ago. Modern day Energy Star compliant ULTs use just 1/3 of the energy. In addition the new ULTs have faster pull down times, higher reliability, longer warranty, automated fault detection and notification capability, and larger interior capacity.
4 ULTs were replaced as a green revolving fund (GRF) pilot project. The initial investment for the 4 new freezers was paid for with energy efficiency rebates that had been collected over the years from other projects. The savings from the freezers is verified and the GRF is paid back annually until it is made whole. This allows the savings to be reinvested into other energy efficiency projects into perpetuity. The performance was measured utilizing IBIS networks plug load monitoring systems. A clear savings in energy consumption is noticed for one of the 4 freezers shown in the graph above. The higher efficiency also results in lower HVAC loads resulting in additional savings not shown.
This project was so successful a large capitol project was initiated to replace approximately 60 more freezers which will save approximately 350,000 kWh/yr.