Low-Temperature District Heating: Fundamentals, Planning and Benefits
Low-Temperature District Heating: Fundamentals, Planning and Benefits
Low-temperature district heating networks – also known as LTDH or 5th generation heat networks – are revolutionizing how we supply heating and cooling to neighborhoods and districts.
What is Low-Temperature District Heating?
Unlike conventional district heating networks that operate at temperatures of 70-120°C, low-temperature networks use natural ground temperatures of approximately -5°C to 25°C. The actual heat generation occurs decentrally through heat pumps at individual consumers.
Operating Principle
- Heat Sources: Ground heat collectors, borehole heat exchangers, wastewater heat, or other low-temperature sources feed the network.
- Distribution: An uninsulated or minimally insulated pipe network transports the medium at low temperature levels.
- Decentralized Heat Pumps: Each consumer has their own heat pump that raises the low temperature level to usable temperatures.
Advantages of Low-Temperature District Heating
High Efficiency
Typical seasonal performance factors of 4.5 to 5.0 for heat pumps mean: 1 kWh of electricity produces 4.5-5 kWh of heat.
Bidirectional Operation
The same network can be used for cooling in summer – the extracted heat is returned to the ground and is available again in winter.
Low Network Losses
Due to the low temperatures, heat losses in the network are minimal – often only 2-5% instead of 10-20% in conventional networks.
Simple Installation
Uninsulated or simply insulated plastic pipes significantly reduce investment costs.
Renewable Energy
Low-temperature district heating is ideal for integrating geothermal energy, solar thermal, wastewater heat, and other renewable sources.
Planning with VICUS Districts
VICUS Districts offers specialized features for planning low-temperature district heating networks:
- Size ground heat collectors: Calculate required collector areas based on load profiles
- Annual simulation: Complete thermo-hydraulic simulation over the entire year
- Network heat gains: Calculate heat absorption from the surrounding ground
- Hydraulic verification: Design and verification of passive or active network operation
Typical Values
| Parameter | Typical Value |
|---|---|
| Network temperature | 0-25°C |
| Annual heat pump efficiency | 4.5-5.0 |
| Network losses | 2-5% |
| Collector area | 1.5-2.5 m²/kW |
Learn more in our tutorial series on low-temperature district heating or book a demo directly.