22 May 2007
Conventional thermally powered water heaters are 80 to 95% effi cient. The new thermally powered heat
pump (TPHP) reported herein is over 140% effi cient. In addition, the cold end of this TPHP produces useful
chilling. The amount of energy-free chilling is equal to the amount of heat pumping. The combination of the
world’s highest hot water heating effi ciency, plus energy-free chilling, all from a single economic appliance,
makes this a very signifi cant development.
This article explains how the TPHP works, making use of an ammonia-water absorption cycle. It also
presents operating results from an ongoing full-scale demonstration of TPHP at a poultry-processing plant,
where a thermal (steam) input of 530 kW produces 320 kW chilled water and 850 kW hot water. It operates
on a 20/5 basis automatically and unattended. The savings in both natural gas and electricity add up to over
$110K per year. The simple payback is approximately 1.8 years.