Thermodinamic and Economic Analysis of Geothermal Heat Pumps for Civil Air-Conditioning

The diffusion of new technologies exploiting the energetic sources and the increased users’ preference for the environmental- friendly ones have led to an increased number of plants using the so-called “alternative” energies and to the development of Research. In recent years, energetic requirement to cool buildings has increased, together with the electrical requirement to power air conditioners. It has surpassed, at least in our country, the amount for heating processes.
This work is a contribution to reduce the amount of electricity used for air-conditioning. It considers many alternative solutions, avoiding the traditional ones.
Energetic saving is one of the most important topic discussed nowadays. This subject is closely related to the problem of global warming; in fact, while the next exhaustion of traditional energetic resources isn’t a certainty, greenhouse gases are surely pollutant. The international scientific community agrees on reducing the emissions produced by the use of fossil fuels (Tinti, 2008). The comparison proposed, an original and interesting study, concerns with the performances of two different systems for civil air conditioning: geothermal heat pump and heat pump with cooled air. The adoption of an air - conditioning system with a geothermal heat pump is a solution which uses the soil as a heat reservoir during the year. This process is less influenced by the seasonal temperature range than by the outside air.
I’ve chosen as case study a commercial building which ideally takes place in three different Italian climatic regions. I’d like to highlight the peculiarities of the installation of a geothermal heat pump for air conditioning, during a warmer summer than the one when this pump has been developed. The pump has been mainly used for winter heating.
According to this theory, European Union is promoting, especially for the construction industry, the diffusion of technologies which don’t use gas, oil or coal. They can lead to a reduction of 80% of energetic consumption and to a great reduction of emissions. In particular, recently in Brussels some public policies have been focused on the “climate - energy – innovation” link, according to the limits of the “Protocol of Kyoto” (the limits will have lowered gas emissions of the 20% by 2020). This relation must be translated into new public policies about the development of new technologies. The concept of sustainability is the corner-stone of energetic policy and the key to competitiveness and security.
The strategic paper of 10 January 2007 "An Energetic Policy for Europe" calls for a new industrial revolution, accelerating the transition to a growth with low emissions of Carbon and increasing, over the years, the amount of produced and used “green energy”. The challenge must optimise European potential competitiveness, controlling at the same time the potential costs (Tinti, 2008).