Renewable heat when cities need it

Heating buildings and urban districts represents one of the largest and most constant energy demands in modern societies. Across Europe and many other regions, district heating networks already supply millions of homes, offices and public buildings with heat.

However, much of this infrastructure still relies on fossil fuels or waste incineration to provide stable heat throughout the day and night. As cities seek to reduce emissions while maintaining reliable energy systems, new solutions are needed that can combine renewable power with predictable heat delivery.

Calora addresses this challenge by enabling cities to store renewable energy as heat and deliver it through existing district heating systems whenever demand arises. In this way, renewable electricity from solar and wind can be transformed into a stable source of urban heat.

The result is a resilient, low-carbon heating infrastructure that supports both new urban developments and existing district heating networks.

Thermal energy storage for urban systems

Calora stores energy as high-temperature heat in ceramic structures designed for long-term thermal retention. The stored heat can later be released gradually and converted into hot water or steam for use in district heating networks.

Because the system can store energy for many hours or even days, it allows cities to balance fluctuations in renewable electricity production. Surplus power—often when solar or wind generation is high—can convert into stored heat and be delivered later when heating demand increases.

This creates a flexible energy system where renewable electricity and district heating work together, improving both energy efficiency and grid stability.

Calora can support a wide range of urban energy solutions, including:

• District heating plants
• Urban energy storage hubs
• Heating for residential and commercial buildings
• Industrial parks and mixed-use developments
• Integration with renewable power systems

By connecting renewable electricity with reliable thermal storage, Calora enables cities to store energy when it is available and deliver heat precisely when it is needed.