Experimental Investigation of a Solar-Gas Driven HVAC System for Temperate Climate
In a pilot installation at Hamburg University of Technology a solar-gas driven HVAC system is investigated experimentally. The coupled operation of a desiccant assisted air handling unit and an adsorption chiller enables a mainly heat driven air conditioning process. This paper presents an experimental evaluation of the system based on measurement data recorded during 2013. A performance comparison with a conventional system in terms of heat and electricity demand is conducted. It is found that through the investigated process up to 54.81 % of the electricity demanded by the reference system can be saved while the heat demand of the pilot plant is 4.8 times higher. Regarding the primary energy demand of both systems, the heat supply of the pilot plant is crucial. If a common gas boiler is used to support the solar thermal system, a solar fraction of at least 65 % is required to achieve Primary energy savings. A modern small scale CHP engine leads to advantages for a well achievable solar fraction of 30 %. A bigger CHP engine leads to increased primary energy efficiency, even if no solar energy is used at all. The advantages of CHP engines can therefore be extended to the summer period.