Lima, NY Home Improves Efficiency with 3 Ton Water-Based Geothermal System
Challenge
This new Net Zero and LEED certified home was in need of a geothermal system.
Solution
A Hydron Module Revolution HWT Series two-stage HWT034 geothermal heat pump (2-2.7 ton/25,500-33,100 BTU/hr max) with water to water heating and water to water cooling capacity was installed in the Customer's mechanical room as a freestanding unit. The heat pump includes a Copleland two-stage UltraTech® scroll compressor, R410A refrigerant, oversized copper coaxial heat exchangers, and an insulated stainless steel cabinet for noise minimalization. The system interconnects to the existing radiant floor heating and to an air handler unit in the master bedroom for future cooling. The system also uses a desuperheater provide opportunistic domestic hot water (the primary domestic hot water is a solar DHW system with electric tankless backup), and includes a 50 gallon buffer tank for the radiant floor heating system. The geothermal ground loops are a water and glycol based closed loop system, consisting of three (3) 200 ft three pipe laying horizontal deep trenches (each 6-7 ft deep and containing 600ft of 3/4" diameter pipe). Complete system monitoring - including the energy production (BTU) of the heat pump and the electricity consumption (kWh) of the heat pump - will be monitored using a custom datalogger system and Halco Monitoring Portal web interface. As designed, this system should function at an annual average COP of 3.0, thus increasing the heating system efficiency from around 95% to 300%, and completely eliminating the use of propane for building heating. With this COP and based on the expected heat load for the building, the geothermal system would require approximately 6,164 kWH/year to operate. As the electricity to operate this system will be generated primarily by an on-site ground-mounted solar electric array, the emission of at least 6,940 Lbs CO2 per year will be avoided.
