The project, funded by the German Federal Ministry of Economic Affairs and Energy under the grant number 3832/03.07_1, aimed to identify and implement heat‑efficiency potentials in representative technology buildings and to develop a future‑proof model for the ownership and operation of WISTA’s own energy infrastructure. The main technical objective was to analyse heat‑side efficiency potentials, evaluate them, and create a concept for heat optimisation measures. Five technology buildings were selected as case studies. For each building a set of optimisation measures was prioritised based on ecological and economic criteria. The resulting comprehensive concept, documented in Annexes 1 and 2, was implemented in the buildings. One proposed measure – the installation of a mixing switch to separate the heating of air‑conditioning units (dynamic heating) from room heating (static heating) – proved to be far more expensive during detailed planning than anticipated in the concept phase. Consequently, in collaboration with the project sponsor in Jülich, the team opted for cheaper alternative efficiency measures that still delivered significant savings. The dynamic heating concept, although not yet standardised and offered by only a few companies, offers the advantage that a hydraulic distribution network for the air‑conditioning units is unnecessary, thereby reducing pump energy consumption and heat losses.

A second key objective was to devise a future model for the ownership and operation of WISTA’s heat and power infrastructure that maximises the use of renewable energies, including waste heat and its injection into the grid, in line with the “heat transition” (Wärmewende). Using a detailed network inventory and assessment, several scenarios for network ownership and operation were developed and prioritised (Annex 3). A trend monitoring exercise focused on Berlin’s energy policy and concession procedures was also carried out, providing insights into regulatory impacts on network ownership.

The project also sought to exchange results with other science and technology quarters and to strengthen the D‑A‑CH cooperation. Regular project meetings, stakeholder events, and D‑A‑CH cooperation meetings were held from 2017 to 2019. However, from January 2020 the COVID‑19 pandemic forced a near‑complete suspension of these activities, and the partners did not continue the D‑A‑CH meetings in an online format.

Collaboration involved multiple layers. The core WISTA internal project team coordinated the work. WISTA.Service, a subsidiary of WISTA, managed the technology buildings and their technical systems. External contractors contributed in specialised roles: Mega:Watt Ingenieurgesellschaft mbH provided technical concepts, AHS Ingenieure GmbH handled technical planning, AURICON Technische Dienste GmbH and ELMATIC GmbH Gebäudemanagement carried out technical implementation, and B. & S. U. Beratungs‑ und Service Gesellschaft Umwelt mbH addressed stakeholder aspects. Bi‑weekly coordination meetings between WISTA and WISTA.Service were held, and task‑specific meetings with external contractors were organised. Partners also presented their findings at national and international conferences and at events organised by the accompanying scientific research.

Overall, the project achieved its primary goals: a detailed heat‑optimisation concept was developed and implemented in five buildings, and a future model for renewable‑energy‑driven infrastructure ownership and operation was established. The technical results demonstrate that dynamic heating concepts can reduce pump energy and heat losses, while the economic analysis guided the selection of cost‑effective measures. The collaboration framework, involving internal teams, a subsidiary, and several external specialists, enabled the integration of technical, operational, and stakeholder perspectives, ensuring that the outcomes are both scientifically robust and practically applicable.