Painted red and white, they can be seen from afar – the newly renovated houses of the municipal housing association GWG at Harthof. It is less obvious that they are a model for Munich’s “local energy transition,” as Mayor Dieter Reiter (SPD) put it on Thursday during a tour of the settlement. Munich’s largest tenant electricity project to date is currently being built on Dientzenhoferstrasse, Rathenaustrasse and Lieberweg for 1.5 million euros. The GWG and the Munich municipal utilities are installing large-scale photovoltaic systems on several buildings, which together are expected to have an output of around 1.8 megawatts peak. This produces up to one million kilowatt hours of green electricity per year.
“We have 850 apartments in the settlement, almost half of them can be supplied with this regional green electricity by the end of the year – that’s quite a number,” explained Björn Heer from the municipal utilities. The project is being implemented in two construction phases, part one is currently the installation of 2,320 solar modules – this corresponds to an area of 4,500 square meters and produces just under one megawatt peak output. Part two will follow next year, so that a further 23 systems with an output of around 820 kilowatts peak will be connected to the grid.
“The home is energetically upgraded by the green electricity system without tenants having to pay for the installation,” said Reiter. In the future, residents will be able to choose for themselves whether they want to switch to M-tenant electricity or keep their existing electricity contract. With tenant electricity from the municipal utility, the green electricity is delivered directly from the roof to the apartments. If more electricity is required than the PV modules produce, the municipal utilities supply additional green electricity. The company assures that M-tenant electricity is always at least ten percent cheaper than the basic supply tariff – the savings are currently even greater.
The municipal utilities have been working since 2008 to generate as much green electricity locally, regionally and nationally as the city consumes. However, this change did not happen quickly enough for the city council: Because Munich only ranked 47th out of 48 major German cities when it came to expanding photovoltaics last year, city hall politicians were extremely dissatisfied with the pace of solar power expansion. In September 2022, the city council therefore set the target of accelerating the expansion to 15 megawatts in 2023. By 2026, the total is expected to quadruple to a peak of 60 megawatts. From 2030 onwards, the municipality would like to cover a quarter of its electricity consumption with photovoltaics. The Munich municipal utility company is expected to contribute half of this.
Mayor Dieter Reiter (right) visits the first large-scale photovoltaic project by GWG and Stadtwerke Munich
(Photo: Florian Peljak)
The municipal utilities and the housing associations GWG and Gewofag now have more than 30 projects with around 70 tenant power systems in progress. The outgoing mayor Katrin Haben Schaden (Greens) stated in June that more capacity had been built up through photovoltaic systems in the first half of 2023 than in previous years. The GWG has now supplied 33 of its own properties in the city with photovoltaics; the goal is to equip all roofs with solar modules by 2030. An ambitious task that requires “pioneering spirit and optimism,” says GWG project manager Philipp Hartmann.
There are also “many flat roofs in Munich where it would be worthwhile to install photovoltaics – on school roofs, for example,” said Mayor Reiter. A suggestion that Manuel Welte from the municipal utilities was happy to take up: “We would be happy to talk to schools,” said the Harthof project manager. The topic could possibly even be integrated into lessons.