Fuel utilization can be dramatically improved through effective recycle of "waste" heat produced as a by-product of on-site or near-site power generation technologies. Development of modular compact cooling, heating, and power (CHP) systems for end-use applications in commercial and institutional buildings is a key part of the Department of Energy's (DOE) energy policy. To effectively use the thermal energy from a wide variety of sources which is normally discarded to the ambient, many components such as heat exchangers, boilers, absorption chillers, and desiccant dehumidification systems must be further developed. Recently a compact, cost-effective, and energy-efficient integrated active-desiccant vapor-compression hybrid rooftop (IADR) unit has been introduced in the market. It combines the advantages of an advanced direct-expansion cooling system with the dehumidification capability of an active desiccant wheel. The aim of this study is to compare the efficiency of the IADR operation in baseline mode, when desiccant wheel regeneration is driven by a natural gas burner, and in CHP mode, when the waste heat recovered from microturbine exhaust gas is used for desiccant regeneration. Comparative analysis shows an excellent potential for more efficient use of the desiccant dehumidification as part of a CHP system and the importance of proper sizing of the CHP components. The most crucial factor in exploiting the efficiency of this application is the maximum use of thermal energy recovered for heating of regeneration air.

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A. A.
,
Slayzak
S.
,
Judkoff
R.
,
Schaffhauser
T.
, and
DeBlasio
R.
,
2005
, “
Performance Assessment of a Desiccant Cooling System in a CHP Application Incorporating an IC Engine
,”
Int. Journal of Distributed Energy Resources
,
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