Combining heat pumps with desiccant dehumidification enables the development of hybrid cooling, heating, hot water, and ventilation systems with improved functionality and reduced energy consumption. The efficiency and performance gains are achieved through independent removal of sensible heat (dry air temperature) and latent heat (heat of moisture). By removing moisture with the desiccant wheel, the compressor no longer needs to cool the air below the dew point, resulting in less electrical energy consumption. Regeneration of the desiccant wheel can be achieved with waste heat from the vapor compression cycle. The same waste heat produces domestic hot water when desiccant dehumidification is not needed.
The energyhawc beta prototype is a significant advance over our alpha prototype, proof of concept and one-off systems. It features a variable speed compressor, electronically controlled expansion valve, low regeneration temperature desiccant wheel, and an additional sensible heat exchanger to help precondition ventilation air. The prototype has also undergone testing using the new ASHRAE 206 standard as a guide. This standard lays out test procedures for new highly integrated home appliances such as energyhawc. Our development has vastly improved the performance and optimized the processes used in energyhawc. Compared to the most efficient set of equivalent residential mechanical systems, the energyhawc beta prototype uses significantly less energy while providing more precise control of temperature and humidity.
Our prototype offers one ton of cooling capacity and 11,500 BTU/hour of hot water generation. Energyhawc is able to achieve high Energy Efficiency and Seasonal Energy Efficiency Ratings which puts the annual cost of operation around $370. This is a 40% savings over equivalent appliances. Furthermore, energyhawc uses a more comfortable forced air architecture and an overall design that does not require an invasive installation such as is found in geothermal systems.