Construction of a Large Thermal Storage Facility in Lemgo

The City of Lemgo is seeking suppliers for the construction of a large thermal storage facility with a volume of approximately 15,000 m³ and a height of 49.5 meters at Liemer Weg, Lemgo. This project includes the installation of various components such as a large air-water heat pump (approximately 3.5 MWth), a heat collector system (approximately 2.4 MWth), two electric boiler systems (approximately 5 MW), electrical and control technology, piping, pumps, valves, and other ancillary facilities. The entire system will be newly constructed, and the project will be divided into several lots (see Part A). Nearby, there are already renewable heat generators (solar thermal system and wastewater heat pump). The thermal storage will utilize excess heat generated and enhance the yield of renewable sources by decoupling heat generation from consumption. Additionally, the storage will maintain the pressure in the district heating network through the static height of the water level in the large thermal storage. This facility will become the central control element for the entire district heating network, allowing for demand-oriented management of heat supply. The construction is planned to be operational by September 2026, with the awarding of contracts in July 2025. This procurement process (EU procurement procedure, Part 2) includes the construction of an electric boiler system (Lot 4), plant technology (Lot 5), electrical engineering (Lot 6), and medium-voltage systems (Lot 8).