DX Upgrades: Sigonella, Italy
Location: NAVSTA Sigonella
Owner: CH2M Hill
Naval Station (NAVSTA) Sigonella is a U.S. government military base on the eastern side of the island of Sicily. It is located approximately 16 miles south-west of Catania, Sicily. Naval Facilities Engineering Command (NAVFAC) contracted Sain Engineering Associates to perform an energy audit of 75 buildings encompassing approximately 1,240,338 square feet (SF) in fiscal year 2012.
One of the many energy conservation methods (ECM) Sain Engineering recommended involves replacing direct expansion equipment from 11 separate buildings. These 11 buildings had various quantities of split system heat pumps. There was a total of 25 different systems that were recommended to be upgraded. These systems ranged from 3 tons to less than 1 ton, and were made by a variety of manufacturers.
The ECM involves replacing the outdoor part of the split system. It also adds better controls for the system. The existing systems utilize R-22 refrigerant or are near the end of their economic life. R-22 is no longer being manufactured and has been phased out of use since the Montreal Protocol amendment of 1992, because of its contribution to ozone depletion. Leaks of R-22 into the environment significantly contribute to global warming. It also produces a greenhouse gas byproduct during the manufacturing of the refrigerant. As the availability of R-22 decreases, the cost of maintaining air conditioning units and heat pumps utilizing R-22 will increase.
The energy savings come from the increased efficiency of the new systems, and with the new controls the systems will be able to run on the optimum schedule set by the user. Sain Engineering estimated that this ECM will save 70,592 kWh, which equates to over $14,600. The estimated implementation cost is $132,188. This gives the project a simple pay back of just over 9 years.
Direct Expansion units using R-410A refrigerant
This ECM could potentially save the base over $14,600 in energy costs.