Cost-Effective and Safe Heating with Green Energy

The 100 prozent erneuerbar stiftung has prepared a feasibility study in cooperation with the district (Powiat) of Hajnówka, Poland. This study investigates whether and how regional wind and solar plants can provide electricity for large-scale heat pumps that replace the combustion of coal in the existing district heating system in Hajnówka. The study was carried out during the project period from August 2021 to June 2023. The results show not only that a sustainable heat supply from renewables is technically feasible, but also that a conversion makes both economic and environmental sense in the long term.

Potential for a climate-friendly heating network

Reduction potential of greenhouse gases

The current district heating system in Hajnówka is largely based on a central coal-fired system. This system is very CO2-intensive, partly due to the use of low-grade coal in the furnace. The graphs show the actual state of the coal-fired boiler and various models with heat pumps, one with mains power, one with renewable energies and one with a storage tank. According to preliminary calculations, full implementation of the feasibility study would lead to a remarkable reduction in CO2 emissions of up to 84 percent, which means heat pumps are used that utilize renewable energies as an electricity supplier and a storage system is installed.

Heating costs with CO2 costs in €

At the same time, heat prices for consumers would remain largely stable over the operating period. The price difference between the scenarios is up to 90 euros per megawatt hour. In contrast, costs for customers would rise significantly if the existing fossil fuel system were to continue operating due to foreseeable increases in coal and CO2 prices. A price increase is to be expected from 2030 at the latest, when European CO2 certificate trading is extended to the heating sector.

The results not only illustrates the potential for decarbonization of the heating sector, but also emphasizes the importance of a sustainable and affordable heat supply for the city of Hajnówka.

The additional results are:

• Pricing is under regional “control” and not dependent on external factors.
• Changes in global fossil fuel prices or the foreseeable increase in CO2 costs then have hardly any impact on the heat production costs.
• The concept guarantees a reliable, affordable renewable heat supply.
• Despite the high initial investment costs of around €25 million, the follow-up costs are calculable and a large part of the added value remains in the region.

The concept is basically transferable to other heating networks. Because of that this project was followed by a similar one with the same objectives: To create a feasibility study to decarbonize a city in a coal region. The only difference is that the city in the new project has three times as many inhabitants: Renewable Power-to-Heat in the Bitola Region. The GAUSS Institute is the lead partner there and the 100 prozent erneuerbar stiftung is the project partner. This allows the experience gained from this project to be incorporated.