This project was part of a program provided by Xcel Energy, Colorado’s largest utility provider, to its customers to reduce electrical demand and consumption, especially during the utility’s peak demand period, and to reduce natural gas consumption through implementation of low cost/no-cost building system performance improvement measures. The program goal was to identify and analyze opportunities to improve operation and efficiency of energy-consuming systems.
Fairmount Elementary School was targeted by the director of Jefferson County Public Schools facilities maintenance because of its high energy costs and high Energy Utilization Indexe.
Existing HVAC systems in Fairmount consist of constant volume rooftop units distributing to multiple spaces through reheat coils, along with some unit ventilators and fan coil units. Heating is provided by hot water boilers, and cooling is provided by air cooled chillers. Systems are controlled by extensive DDC systems. Most interior lighting control is manual, with exterior lighting controlled by photocell and/or timeclock.
EEI recommended multiple energy improvement measures at the school, including converting to a variable flow HWS, replacing boilers with more efficient units, and reducing the kitchen hood at unnecessary times. EEI calculated the total estimated savings potential for these measures from the perspective of Fairmount’s utility bill to be 17 kW total summer peak demand savings, 169 kW total winter demand savings, 66,393 kWh annual energy savings, and decreased gas energy consumption of 804 DkTs.
Annual cost savings are estimated to total $11,132 with an estimated implementation cost of $84,510 for a payback of 8.8 years. These are raw figures that do not include Xcel Energy recommissioning rebates, prescriptive rebates for variable frequency drives or possible custom rebates for the boiler replacement. These rebates, if awarded, will significantly reduce implementation costs.
EEI is currently providing services to commission the selected measures as implemented by contractors for the school district.