Heating Firma van Buiten with aquathermal energy

The Firma van Buiten building is heated using aquathermal energy extracted from the adjacent pond. This sustainable system harnesses low‑temperature heat from surface water without disturbing aquatic life. Even in winter, the water contains enough residual heat to warm the building. This installation serves as a pilot within an international effort to scale up aquathermal energy solutions.

Why this research?

Aquathermal energy (AE) – extracting heat or cold from nearby surface water – can make a significant contribution to the energy transition. Water in canals, lakes, or ponds retains usable warmth throughout the year, enabling efficient electric heat pump systems that reduce reliance on natural gas.

Despite its potential, AE is not yet widely applied at scale. There is a need for real‑world data on performance, ecological impact, and system design, especially in challenging conditions such as shallow water bodies. This project aims to provide such data and insights. The results will support Project WaterWarmth, which focuses on accelerating the adoption of aquathermal systems across Northwest Europe.

TU Delft collaborates with Firma van Buiten, funded by the Campus Innovation Committee (CIC) and Interreg North Sea Region.

Facts & figures

Location: Firma van Buiten
System installed:
- Heat extraction from the adjacent pond using a sealed aquathermal system
- Heat pump installation for building heating
- System designed to protect freshwater ecology
Focus of the pilot:
- Demonstrating AE performance in shallow water conditions
- Understanding environmental and thermal behaviour of small water bodies
Effects being studied:
- Heating performance and system optimization
- Seasonal temperature behaviour of the pond
- Ecological impact and biodiversity
- Scalability and design considerations for wider application
Part of: Project WaterWarmth (Interreg North Sea Region), which develops and monitors AE pilots in five European countries