The Colorado State Capitol building in Denver achieved $95,000 in first-year utility bill savings after undergoing an HVAC system retrofit, HPAC Engineering reports.
The Colorado Capitol Complex was slated for a major renovation and restoration by the Colorado Department of Personnel & Administration (DPA) in 2003. Under the state’s Renewable Portfolio Standard (RPS), Colorado is required to use 30 percent renewable energy by 2020, so the DPA sought a retrofit solution that would increase the energy efficiency of the buildings and also incorporate renewable energy.
DPA worked with Chevron Energy Solutions (CES) to plan $30 million in upgrades to the governor’s residence, the Colorado Department of Revenue building and the Colorado State Capitol building.
For the State Capitol building, CES designed a $6 million hybrid system that integrates a 23-ton geothermal heat-pump system with a 10-kW solar PV system. A network of nine ClimateMaster water-to-air and water-to-water heat-pump units were integrated with an open-loop geothermal system utilizing the Arapahoe Aquifer, located about 900 feet below the State Capitol building.
Installation began in the fall of 2010 and took approximately one year to complete.
The geothermal system was funded by a $4.6 million US Department of Energy grant and $1.4 million in state-funded certificates of participation and a lease-purchase agreement with CES.
By 2029, the system will save an estimated $165,000 per year in energy costs. The system has an estimated payback period of 10 years.
Other energy-saving improvements at the complex included installing energy-efficient lighting systems and making building-envelope improvements.
Photo via Shutterstock.
