Analysis and comparison of performance of two small-scale Trigeneration plants: an ICE with a liquid desiccant cooling system and a MGT with an absorption chiller.

Two natural gas small-scale trigeneration plants are presented in the paper. Both plants are going to be started-up at the Politecnico di Torino (Turin, Italy) and are part of a new cogeneration and trigeneration systems laboratory, which is going to be setup and exploited for scientific and technical purposes. The first plant has 126/220/210 kW electrical, heating and cooling capacities, respectively, and is characterized by an innovative internal combustion engine that has been coupled to a liquid LiCl-water desiccant cooling system, which provides cooled and dehumidified air to a classroom building. The other plant has 100/145/98 kW electrical, heating and cooling capacities and is composed of a natural gas micro gas turbine, coupled to a LiBr-Water absorption chiller, which provides cooled water to the internal cooling grid at the Politecnico. The paper has the aim of comparing the performances of the two plants from an energetic and economic point of view; the Primary Energy Savings are calculated through different methodologies reported in literature for both installations, and the results are compared and discussed. A comparison of the economic performance offered by the two plants is also reported, together with a sensitivity analysis on the influence of subsidies foreseen by Italian Legislation on economic profitability.