Solar cooling: a case study

Throughout the years various methods for heat prevention and indoor temperatures control in the summer have been used. The alternative cooling strategies are based on various passive and low energy cooling technologies for protection of the buildings via design measures or special components to moderate the thermal gains, or to reject the excess heat to the ambient environment. All these techniques aim to reduce summer cooling loads and electricity demand for air conditioning. During the summer the demand for electricity increases because of the extensive use of heating ventilation air conditioning (HVAC) systems, which increase the peak electric load, causing major problems in the electric supply. The energy shortage is worse during ‘dry’ years because of the inability of the hydroelectric power stations to function and cover part of the peak load. The use of solar energy to drive cooling cycles for space conditioning of most buildings is an attractive concept, since the cooling load coincides generally with solar energy availability and therefore cooling requirements of a building are roughly in phase with the solar incidence. Solar cooling systems have the advantage of using absolutely harmless working fluids such as water, or solutions of certain salts. They are energy efficient and environmentally safe. The purpose of this paper is to describe a Solar Cooling System to be installed on the roof of a building in Rome, the headquarters of the State Monopoly. The medium size power plant is composed of the following components: − Solar Collectors; − Thermal Storage Tank; − Absorption Chiller; The plant design is based on a dynamic simulation in TRNSYS, a dynamic simulation tool used by engineers all over the world to make energy calculations in a transient state.