How can more renewable energies be used and at the same time the costs for individual households be kept low? The EU research project Sim4Blocks, which was launched in 2016 and is now in its final phase, addresses precisely this question and seeks the solution in relation to buildings and their occupants.
Over four and a half years, innovative load management systems were tested at three locations in Germany, Spain and Switzerland. Natural fluctuations in renewable energies are taken into account so that consumers can adapt their electricity consumption to the supply. A consortium of 17 European partners took part in the project. In September 2020, the ceremonial conclusion of the project took place in Wüstenrot, the German pilot site. During a public event with an address by the mayor Timo Wolf, interested residents of the community, members of the municipal council and a representative of the Baden-Württemberg state parliament were presented the project results and the significance of these for the citizens of Wüstenrot. A guided tour through the PlusEnergy settlement Vordere Viehweide afterwards illustrated the project work. Innovative load management: purpose and significance Sim4Blocks is a research project funded by the European Union's Horizon 2020 funding programme. Within the framework of Sim4Blocks, innovative load management procedures are being developed for private and commercial use. In the project, decentralised energy management technologies are linked for load regulation at neighbourhood level. Why is load management necessary and what does it mean? AC electricity grids must be operated at a constant frequency. In Europe, this frequency is 50 Hertz. This is done by keeping electricity supply and demand in balance. When electricity was generated almost exclusively from fossil sources and nuclear power, this was possible without difficulty. The energy provided could be easily adjusted to demand by switching power plants on and off, so that the grid frequency remained constant. However, the expansion of renewable energies (RE) creates an imbalance in this respect, as these energy sources are subject to natural fluctuations. Nevertheless, the further expansion of renewable energies is a key pillar of European and German climate and energy policy to counteract man-made climate change. In the context of the "Climate Protection Plan 2050" it was decided for Germany to push ahead with the expansion of renewable energies from a share of 40% of gross electricity consumption in 2019 to a share of 65% by 2030. Intelligent networking and adapted demand This gives rise to the problem that the steady expansion of renewable electricity generation already poses challenges for the electricity grid today. The use of intelligent networking (Smart Grid) and an adaptation of energy demand to the energy supply, so-called load management, can counteract the frequent shutdown of renewable energy producers at peak load times and disproportionately high investments in network expansion. Consumers adapt their electricity consumption to the amount of energy available at any given time. As a rule, this means a shift in electricity consumption away from periods of low renewable energy production towards times when more power is available, e.g. when the wind is blowing. Consumers thus take a more active role in the operation of the electricity grid. In the Sim4Blocks project, researchers have tested the load management systems and services at three pilot sites in Germany, Spain and Switzerland. A particular focus was on load management using heat pumps. Due to their efficiency, heat pumps offer an ideal interface to connect the electricity sector with the heat sector ("Power-to-Heat"). The aim was also to develop interfaces that allow intuitive use. Basically, a focus was placed on neighbourhoods with low-energy houses, different energy supply systems and an infrastructure that allows the testing of load management strategies. Location Wüstenrot (Germany) In the rural community of Wüstenrot, heat pumps together with a cold local heating network and a large-area geothermal collector (agrothermics) were investigated. One of the aims was to reduce the own consumption of the electricity generated by photovoltaics and thus to reduce the electricity costs of the residents. A further aim was to examine the individual technical hurdles to the realisation of a virtual power plant, i.e. a combination of individual consumers and producers. Location St. Cugat (Spain) In Spain (St. Cugat near Barcelona), an office and residential building complex was investigated in the Sim4Blocks project. This covers various uses from the service industry to social housing. Load management for the heating and cooling technology was carried out. The residents were additionally motivated to participate in flexible electricity tariffs by a specially developed app. Location Naters (Switzerland) In Switzerland (Naters near Brig) a cold local heating network with decentralized heat pumps and groundwater as a heat source similar to the one at the Wüstenrot location was also investigated. The aim of this part of the project was also to develop cost-effective components for heat pump control for load management, in order to enable affordable retrofit solutions in existing buildings. In addition, an aggregated operation together with an aggregator company, i.e. someone who remotely controls individual consumers and producers and bundles them into a virtual power plant, was implemented here.