Wastewater heat NRW: The hidden energy source for our cities!

Wastewater heat NRW: The hidden energy source for our cities!

In North Rhine-Westphalia, a promising project is currently being launched that not only drives climate protection forward, but also supports the energy transition. The initiative of wastewater heat NRW, carried out by NRW.ENERGY4CLIMATE in cooperation with energy suppliers, water management, sewer network companies and the housing industry, has set itself the goal of expanding wastewater use in the country. But what exactly is behind this innovative idea?

Around a dozen use of wastewater heating projects are already running in NRW, and the potential is enormous. Wastewater from sewage treatment plants or channels offers a constant temperature of around 10 to 20 degrees Celsius, which makes it an economic heat source. For example, Duisburg uses the residual heat from clarified wastewater to supply more than 1,000 households. But a wastewater heat pump is also used in Lemgo, which helps with district heating. "Wastewater heat is ideal for densely populated quarters, apartment buildings and facilities such as retirement homes", the initiative provides an insight into the versatile applications.

The advantages of wastewater heat

The use of waste water for heat generation not only offers ecological advantages, but also economic. Wastewater usually has low seasonal fluctuations and can be used both in the cold season for heating support and in summer to cool buildings. In metropolitan areas, high amounts of waste water often correlate with a high heat requirement, so that the technical development of this heat source is both practical and sensible. Heat exchangers and heat pumps make it possible to use the heat efficiently and to integrate into the existing heating networks.

The estimates show that in North Rhine -Westphalia there is a theoretical potential of around 1.6 gigawatt thermal performance of both sewage treatment plants and the sewage system, which could cover about ten percent of the total district heating requirement in the federal state. Nevertheless, this potential has so far only been used slightly, which means that a lot of unused heat sources are still available here.

A look into the future

The initiative aims to initiate several hundred projects in North Rhine-Westphalia and thus become a leader in the use of wastewater heat throughout Germany. The key to successful implementation lies in the close cooperation between municipalities and operators of sewer and sewage treatment plants. In order to exploit the full potential, municipal decisions and strategies are essential.

In order to offer those responsible in the municipalities in the municipalities, the Association of Local Companies (VKU) and the German Association for Water Management, Wastewater and Waste (DWA) have published a helpful handout for efficient use of wastewater heat. This brochure deals with legal and technical questions and should serve as a guide to promote the exchange between the various actors.

In addition to the opportunities that the wastewater heat offers, other sustainable heat sources such as industrial waste heat and geothermal energy are also important. Especially in cities such as Krefeld and in Münsterland there are promising geothermal potential that should also flow into heat planning. NRW.ENERGY4CLIMATE provides a checklist for determining this potential for municipalities.

The future of wastewater heating looks promising. Through innovative projects and the smart mix of various renewable energy sources, North Rhine-Westphalia could make a decisive contribution to climate protection and at the same time improve local heat supply. So let's see what the coming years will bring and what options the wastewater heat can still develop. For detailed information on the initiative and the projects, visit the pages of Energy4climate and municipalities. .