District Heating and Cooling Thermal Microgrid Feasibility Study

Vernal, Utah

A project has been conceived to implement Grid Amplified Building Energy Seasonal Storage (GABESS) in a District heating and cooling thermal microgrid (DHCM) in Vernal City, Utah. GABESS is an integrated system of geothermal heat pumps, air source heat pumps, and borehole thermal energy storage (BTES). The DHCM will be a closed-loop pipe network that circulates water to each building. At each building, a water source heat pump will be used to provide heating and cooling, depending on each building’s particular needs at each moment in time. Building occupants will never know that the system has changed.

The Feasibility Study will evaluate whether a GABESS system installed in Vernal, Utah, would provide a) economic benefit to the building owners who chose to connect and b) long-term financial sustainability for the City as Owner/Operator. A successful study will enable a follow-up front-end engineering design study and the beginning of infrastructure investment when opportunities arise (such as putting DHCM pipe in open trenches in the street for future use, starting in March 2023).

The technical factors to be examined include building HVAC energy performance, capital cost, and carbon dioxide reductions by conversion to the DHCM, the piping network configuration that links all the buildings, and the BTES configuration and modes of operation. Economic analyses will be performed, and overall system energy and emissions profiles and resilience will be summarized. The benefits that GABESS provides to the ratepayers of Rocky Mountain Power will be calculated to garner RMP’s financial participation.

7. Due Diligence