Heating with geothermal – the ambitious plans of Munich, Germany

Panorama over Munich (source: flickr/ DAVID HOLT, creative commons)

Alexander Richter 9 Jan 2017

The ambitious plans to fuel its complete district heating systems with geothermal energy of Stadtwerke München, the city utility of Munich in the South of Germany are incredible and a good example for other cities.

On our partner website TiefeGeothermie in Germany, the fantastic ambitions for geothermal heating in the city of Munich are covered in detail in a recent article.

Here is a translation of the article, somewhat adapted for readability.

At this year’s UN Climate Summit COP22 there was a consensus that global climate change has reached an irreversible stage. Therefore, in the ” Marrakech Action Proclamation” delegates called upon not only governments and science, but also companies to help to limit global warming.

One company that has devoted itself intensively to this topic for more than half a decade is the city utility of Munich (Stadtwerke München). Its “expansion campaign Renewables” is firmly built into the ” Integrated Action Programme for Climate Protection” for the city of Munich. Already started in 2008, the utility has budgeted EUR 9 billion ($9.4 billion). By 2025, the plan is to produce as much electricity from renewable energy sources, as the whole city needs. Last year, SWM already achieved part of that goal with all private households in Munich and public transport having been supplied by renewable energy.

SWM wants to achieve a similarly ambitious goal in the heat market, and a large part in its future energy plans, plays geothermal energy for district heating for the city.

At a press meeting in November 2016, Stephan Schwarz, Managing Director of SWM, said that “the drive towards energy from renewables is not only a drive towards electricity but also towards heat from renewable energy sources. Significantly more energy is used for heating. Apart from a drive to energy saving and more insulation, there needs to be more work done on utilising renewables for heating .”

“We have the opportunity in Munich […] to make the grown district heating utilise renewables,” says Schwarz.

In its plans for district heating laid out until 2040, the city of Munich will likely the first German city whose district heating will be fully covered by renewable energy. So far, the city is focused primarily on accelerated development of geothermal energy projects to live up to its plans. The vision is now becoming a reality. The utility has already several geothermal energy fuelled heating plants in the city and the Greater Munich area. Two of them are of particularly strategic importance for district heating in the urban area.

More than 10 years ago, the first geothermal heat plant started operation in the district of Riem in the east of Munich. Since then, the 13-MW (thermal) plant has supplied the residential development near the convention area, the adjacent commercial enterprises and Messe München to a large extent with deep geothermal heat. In 2016, the district heating of the Freiham district of Munich was connected and is already fuelled by geothermal. The district heating of Freiham is already connected to the municipal district heating network, with the plan still being in an optimization phase.

A third district heating system is then planned to close the east-west axis from both locations in the east and west. To supply the whole city area, three additional geothermal district heating systems are to follow. It is so far not clear yet where exactly they will be positioned, as this is till being part of project planning and the evaluation of different locations. They will play a rather important role for the big heating plans for the utility. The connection of the north-south axis is then planned by 2025.

From gas-and-steam will be geothermal energy

Munich has a historically grown district heating network, which was originally operated as a steam network, with correspondingly high temperatures. But now the grid has to be switched, from a high-temperature network to low temperature, from condensate to glass fiber cables. In order to ensure the long-term supply of geothermal energy in the long term, more medium with higher pressure must be transported through the pipelines. Therefore, the line network must be renewed and cable trunked at other locations. The conversion of a total urban steam network to a low-temperature network has nearly been completed for half of it. “To make the district heating regenerative, that is an undertaking, which has not yet taken place in this form”, Schwarz stated in the context of the project presentation.

For a new plant, the utility will utilise an existing thermal heating plant currently in operation.

It is also a pioneering achievement on the international stage, which the Stadtwerke Munich with its district heating vision 2040 provides. This was confirmed by the German Geothermal Association, which sees SWM’s district heating system as the world’s most ambitious project in this form.

While many cities have long elaborated on alternative solutions in the context of future city planning 3.0, Munich has recognized the signs of times at an early stage and been tapping the natural resources of the city that can supply efficient and clean heat supply. The utility shows a well thought out concept and long-term plan, instead of single solutions, which will play a major part in a significant transfer to a renewable energy fuelled heating supply.

The example of geothermal utilization in Munich is not easily transferable to other cities due to geological and hydrochemical conditions. In principle, suitable geothermal potentials are also available in other cities, but there is a lack of commitment and political will to implement such master projects.

With geothermal energy, the utility of Munich, is utilising an energy source that has long been denied being able to play such an important role for the heating of a city. This highlights once more that geothermal energy should play a stabilising factor, both as a baseload source of energy within climate change efforts and a change of energy supply towards renewables. It further can provide a renewable energy supply for an efficient energy supply for the city of tomorrow.

Adapted from TiefeGeothermie