Research Project Summary Information
Geothermal Dehumidification & Radiant Hydronic Cooling Systems in Balanced Ventilation Homes (ST9986-1)
Michael McDonough Architect PC
E-House is a building in the Hudson Valley of New York that has been constructed by M. McDonough as an experiential learning and testing home of advanced building concepts. The home is equipped with in slab radiant floor heating and an energy recovery ventilation system. Currently, homes with radiant floor heating usually are not candidates for same source mechanical system air conditioning, as are homes that have furnaces where common duct work can be shared to distribute the conditioned air. This scenario is usually cost prohibitive for a home owner to consider; having two mechanical sources, one to provide heat, and the other to provide cooling.
The project endeavors to develop a ground- coupled dehumidification and cooling system and demonstrate that ground source coupling of dehumidification and cooling functions can considerably reduce the vapor compression cycle of conventional home air conditioning systems. An Energy Model analysis will be performed on the parameters of this concept. If the energy model reveals American Society of Heating, Refrigerating, and Air Conditioning Engineers, (ASHRAE) acceptable comfort levels, the system will be built using conventional mechanical equipment and tested for energy performance.
Significant electrical energy consumption from the operation of an air conditioning compressor will be avoided. Dual utilization of installed tubing for both heating and cooling may be possible. Estimated energy reduction for the proposed geothermal dehumidification and cooling system at the E-House is expected to be significant, on the order of 1/6th the energy required for cooling season from mid-May through mid-September. This installation represents a possible alternative to a conventional compressor driven, energy intensive air conditioning system. Full cooling season testing and data logging will capture adequate data to make a fair comparison of energy -to -energy expended for running the system that has been developed.
The project team designed, engineered, installed, implemented, and commissioned a functioning geothermal dehumidification air exchange system that uses a well built building shell and energy recovery ventilation (whole house) system. Preliminary data collection initiates interest to further collect data for valued comparison against a conventional method of air conditioning. The project team found that instead of advocating that dehumidification is a primary air conditioning strategy, if properly engineered, effective ASHRAE 55-2004 conformant cooling will simultaneously follow. Effective cooling season dehumidification can reduce cooling loads by up to 70%. The properly ventilated air actually surpasses air conditioning in terms of delivery and economics. This favorable dehumidification is achievable at coil temperatures of 58 deg. F and lower, which aligns well with average annualized groundwater temperatures for New York State, 50 - 55 deg F. Availability of this groundwater, coupled with balanced ventilation and heat recovery and ducting, has demonstrated initially that the system can indeed provide energy efficient compressor-less air conditioning that meets or exceeds ASHRAE 55-2004 standards for human comfort 100% of the time.
Michael McDonough Architect PC
131 Spring St
New York, NY 10012
Heating, Ventilation, & Air Conditioning
Cooling & Ventilation
NYSERDA Contact Information
R&D - Buildings Research