| Abstract |
Today, heat pumps are mainly used in developed areas of northern and central Europe. Recent modern, and in particular, large heat pump projects, i.e. for heating and cooling of big shopping centres, are planned to be energetically neutral and used for the interior air conditioning - heating and cooling. In such manner, the operation costs can be reduced up to 45 %, as cooling is based on a passive principle using the cold stored during winter. In order to introduce the utilisation of heat pumps in a warmer, Mediterranean climate of Europe, and reduce enormous energy consumption for cooling during summer and lower the emissions, a five-year-project termed »Advanced ground source heat pump systems for heating and cooling in Mediterranean climate« has been approved by the 7th EU Framework Programme, Theme 5 (energy). The project joins 24 companies and institutions from 13 EU countries. Slovenia is represented by Gejzir Consulting from Ljubljana. The goal of the project is to reduce the share of electric power consumption to less than 20 % with respect to the total heat production. The pay-back of investment compared with the gas boiler of the same power must be less than seven years and the operation time at least 20 years. The project partners are obliged to develop the prototypes of heat pumps characterised by an improved capacity and more simple operation of the system. Eight demo-sites were built in the frame of the project: »The Benedikt Culture Centre Demo Project« in Slovenia, Septemes les Vallons in France, University in Oradea, Romania, Fábrica dos Mirandas in Coimbra, Portugal, Polytechnic University in Valencia, Spain, »Solar Plant« in Barcelona, Spain, the HiRef company plant in Tribano, Italy, and the business building of the company Edrasis in Athens, Greece. The Culture Centre Benedikt is a multi-functional building. An auditorium with 120 seats and the division for guests and employees in the ground-floor encompass an area of 240 m2. In the attic, a meeting room and business lounge encompass 88,5 m2. An old boiler that used extra-light oil has been replaced by a modified and improved heat pump, the model GMWW23p, which was constructed by the project partner, the company Ochsner. The existing hightemperature heating system was preserved in the original form. The system of ventilation with a heatexchanger has been newly constructed and enables cooling or heating of the incoming air. In this manner, the existing high-temperature system has been changed into a low-temperature system. The heat pump is connected to the system of three BHEs reaching depths of 166 m, 125 m and 98 m, respectively. The system enables active heating and cooling, and passive cooling. Because of the passive cooling, the BHEs are connected into one hydraulic loop. As a medium, pure water free of additives has been chosen. A double U-heat exchanger GEROtherm EWS 4x40 mm produced by Haka Gerodur from Switzerland has been installed in each well, and the wells were finally filled by the ThermoCem PLUS cement produced by the HeidelbergCement from Germany. The heating of the building started in October17, 2011. During the first heating season (till October 16, 2012) the heat pump operated for 2008 hours and emitted 30 MWh of heat in the heating system. The share of energy obtained from the heat exchangers amounted to over 82 % |