Thermal waste recovery
GEOTHERMAL ENERGY AND THERMAL WASTE RECOVERY FOR A MANUFACTURING COMPANY
A historic Company from Northern Italy, specialized in cold molding of fasteners, asked Geonovis to develop the project for the air conditioning system in its new production site (a newly built structure of 6.000 sqm production area and 700 sqm offices). The goal was to design and install a system focusing on the quality and functionality of all components, exploiting renewable energy sources (shallow geothermal energy) and processing thermal energy which would normally be dissipated.
The solution adopted to serve the newly built plant (for heating in winter and cooling in summer) has been envisioned to valorise as much as possible the thermal waste generated in the compressor room, capable of providing up to 210 kWt.
The water-to-water geothermal system draws thermal energy partly directly from the aquifer, and partly from pre-heated water by the heat recovery from the production stages, with very remarkable results in terms of energy savings.
All ideal conditions were present in this specific case both at the technical and geological level for the choice of a shallow geothermal solution. In particular, an open-loop system (water-to-water) was undoubtedly the best option considering the specific features of this site. Groundwater (with a constant temperature of 14°C all year round) is in fact an abundant renewable resource in the area (Province of Vercelli, in Piedmont Region).
The sizing of the geothermal system was defined to satisfy the start-up of the facility: it is able to guarantee the overall thermal needs even without simultaneous production activities. Following the start-up of the compressors, for example at the beginning of the work week, an increasing share of recovered thermal power will be provided, thus allowing the gradual reduction of the power supplied by the geothermal system.
Data analyses show that the total heat recovery achieved thanks to this approach is approximately 3.200 kWh/day.
The heart of the geothermal plant is composed by 2 heat pumps with dual compressors. This aspect ensures a modularity of the delivered power in order to meet the thermal demand according to the real needs of the building, allowing additional energy savings and efficiency.
Technical details
The facility
Area to be air-conditioned: 6000 sqm plant + 700 sqm offices
Distribution systems: ceiling fan coils (office areas) thermo-ventilated (production areas)
Heat requirements: 210 kWt in heating and 110 kWt in cooling
Climatic zone: E
Degree days: 2.537
The geothermal system
Type: groundwater (open-loop)
Installed power: 210 kWt
Functions: heating, cooling (free and active cooling)
PDC: n. 2 double compressor
Accessories: heat recovery from production process