Evaluation of Geothermal Heating for Caltrans Facilities

摘要

The research project evaluated the geothermal heating system at the Caltrans District 08 Office in San Bernardino and identified other potential geothermal project sites. The research indicates that the new geothermal heating system installed at the San Bernardino District 08 Office is cost-effective and reliable. The payback period for the system is 2.5 years. The system would run more efficiently if the building's air handler coil size was increased to transfer more heat into the building's air, but this additional improvement is not cost-effective. The domestic hot water could be heated by the geothermal energy, and with the most expensive system design (a new double wall heat exchanger), the payback period would be 3.2 years. Five Caltrans sites were evaluated for the possibility of using geothermal energy to meet building space conditioning loads. A dollar limit was determined as the cost to provide geothermal energy with a 10-year payback period for each site. The sites (and limits) were the District 2 Beckworth Maintenance Station ($73,000), the District 4 Calistoga Maintenance Station ($9,900 to $19,800), the District 9 Lee Vining Maintenance Station ($37,000) and McGee Maintenance Station ($40,000), and the District 11 El Centro Maintenance Station ($26,000).