SUPPLY OF COOLING AND HEATING WITH SOLAR-ASSISTED ABSORPTION HEAT-PUMPS - AN ENERGETIC APPROACH

The primary energy consumption of two kinds of solar assisted absorpti on systems (solar assisted absorption chiller during summertime and he at pump during wintertime or solar assisted absorption chiller with di rect gas combustion for heating during wintertime) is compared with th e primary energy consumption of a compression chiller which can work a s a heat pump during wintertime. For the absorption systems three tech nical options were considered: a single effect machine; a double effec t machine with the solar energy delivered to the lower temperature des orber and combustion heat of a gas burner delivered to the higher temp erature desorber; a double effect machine with both solar energy and c ombustion heat delivered to the higher temperature desorber. The analy sis performed in this article shows that solar assisted absorption chi llers, absorption heat pumps and direct solar heating systems even wit h low and intermediate solar fractions can operate with considerably l ess primary energy consumption than compression systems. Further, the necessary solar collector area to achieve that goal is compatible with roof area available in buildings. It was also verified that, for the double effect absorption machines, there is no advantage in delivering the solar energy to the higher temperature desorber, thus establishin g as preferable the solution in which it is delivered to the lower tem perature desorber. (C) 1998 Elsevier Science Ltd and IIR. All rights r eserved.