In Freiburg Dietenbach, a new district is being built for about 16,000 people. The heat will be supplied via a district heating network from a central heat generation plant. Large-scale heat pumps will be used, which use groundwater and wastewater as heat sources, and in addition, the new energy center = EZ will be integrated into the WV West. Several low-temperature heat pumps and high-temperature heat pumps with the refrigerant ammonia are planned. In addition to the heat pumps, the groundwater heat exchangers, waste water heat exchangers, pressure maintenance, pumps, control cabinets, transformer stations and also small ancillary rooms such as storage, toilets and social rooms are also accommodated in the development cooperation. The media district heating, groundwater, sewage and electricity must be introduced into the building in development cooperation.
The building should be completed at the end of 2025 so that plant construction can then begin, which will take about a year. The supply of heat from the new development cooperation is scheduled to begin at the end of 2026.
building
The energy center is designed as a large machine hall. The heat pumps are installed in a separate room within the hall due to the toxic refrigerant ammonia. This room must also be equipped with storm ventilation in case of refrigerant leakage. There will be large gates for the insertion and removal of the large machine parts. For the installation of the pipelines within the hall, a second level is partly built on a second level in steel construction. The floor area for the building is 60 m x 30 m. The height of the building is 8 m. In the outdoor area, three buffer storage tanks with a volume of 150 m³ will be built next to the building, for which appropriate foundations will have to be built. There will also be social rooms in the energy centre. The façade is to be clad with wood. If necessary, there should be a photovoltaic system on the roof or partly also on the façade.
The scope of this call for proposals includes service phases 2-8 for, among other things:
Trade building:
•Civil engineering
• Shell construction, interior fittings and roof
• Painting and floor coating
• Windows and doors
• Building electrics (lights, sockets and emergency lighting, etc.)
• Drainage, water and sewage pipes
• Sanitary installation (drinking water connection, toilet, sink, sink)
• Foundations of the energy center and buffer storage tank
• Steel construction in the energy center
• Lightning protection and grounding
•Fire protection
•Outdoor installation
• Access and parking spaces in front of the building
Optionally, other services can be offered in addition to this tender, e.g.
• Structural engineering / structural analysis
• surveying
• Geotechnical survey
• Schallschutzkonzept
• Fire protection concept
• Health and Safety Coordinator
Plant construction trade:
• Heat generation system consisting of large-scale heat pumps
• Groundwater heat exchanger
• Waste water heat exchanger (optional at a later date)
• Heat exchanger between NT and HT circuit
• Mains pumps, pumps in the plant
• Groundwater pumps with frequency converter control
• Shut-off and control valves, safety devices, dirt filters
• Shut-off and control valves in the injection wells
• Pipelines with thermal insulation with sheet metal jacket
• Buffer storage in the outdoor area
• Measuring equipment (heat, pressure, temperature)
• Room cooling via groundwater
• Druckhaltung
• Automatic water replenishment with water treatment
• Storm ventilation for the installation room of the heat pumps
• Sanitary installation (toilet, sink, sink)
• Fastening systems and steel construction for pipelines (partly also at the architect's site)
• I&C technology for the entire system with remote access and fault message forwarding
• fire protection
•Documentation
Electrical installation:
• Control cabinets for electrical distribution
• Wiring for power cables
• Transformer stations
• Cabling for low-voltage and data network
• Cabling for I&C technology
•Electricity meter
• Lighting, sockets
• Grounding and lightning protection
• Cable management system consisting of flatbeds and pipes
•Documentation
This tender includes:
• Adoption of previous drafts, sketches and calculations, also from the urban planning department of the city of Freiburg
• Coordination with the other trades and planning according to the service phases of the HOAI, preliminary planning up to object supervision (HOAI service phases 2 to 8)