Geothermal HP versus VRF in Multifamily Applications

In 2013, BPA received an unsolicited proposal for a case study for a side-by-side comparison of a geothermal heat pump and variable refrigerant flow (VRF) system in nearly identical multifamily housing units in Tacoma, Washington. The project provided a unique opportunity to evaluate these two technologies while providing an application for multifamily housing. The project will determine how the seasonal performance of the two systems for space conditioning and production of hot water compares. The following information will be provided for the operation of both units: quantified savings and costs over a specific baseline; understanding of the engineering design, installation, ownership, and possible utility barriers; quantified annual energy savings, benefits, and costs; documented magnitude and longevity of the incremental electric energy savings; documented operation and energy use; and described energy savings time of occurrence and duration, load shape, and lifetime.