The NEB Tischlerei Melk project demonstrates how former industrial sites can be transformed into climate-neutral, future-ready districts powered entirely by renewable energy. At its heart is an innovative heat pump concept developed by Heliotherm: a fully modulating “Triple Heat Pump” system consisting of two individual units capable of intelligently selecting the most favorable of three renewable thermal sources to maximize efficiency under changing operating conditions. The current design combines geothermal boreholes, ambient air and an adiabatic cooler (with an ice storage system being evaluated as an alternative), allowing the system to utilize the most suitable energy source throughout the year.
The project addresses one of the key challenges of the energy transition: how to combine highly efficient heating and cooling with fluctuating renewable electricity generation while supporting grid stability. To achieve this, the heat pump is integrated with predictive energy management, photovoltaics, thermal and electrical storage systems, and demand-side flexibility. The system continuously adapts to weather forecasts, energy demand and renewable energy availability.
By combining renewable heating and cooling, smart control, district-scale flexibility and circular urban regeneration, the project showcases a practical blueprint for future net-zero communities that can be replicated throughout Europe.
