Little is happening in Bavaria: the solar autobahn remains a utopia
Created: 02/14/2022, 07:01
By: Dirk Walter
This solar roof is to be realized on the A81 near Hegau (visualisation).
© BMVI
There are thousands of noise protection walls and embankments along motorways in Bavaria.
Why aren't they equipped with solar cells?
But it's not that simple - the highway authority can give umpteen reasons why solar often doesn't work.
After all, two important pilot projects are now being tackled.
Munich/Germering – The Baden-Württemberg Ministry of Transport has announced that it will make areas available for photovoltaic systems along federal and state roads.
The idea is not new - in Bavaria, too, municipalities are increasingly asking whether they can use areas on the motorway for solar projects.
So far, this has only been done sporadically, for example on the Salzburg A 8 motorway near Unterhaching.
It is currently the municipality of Kirchheim (Munich district) that wants to set up solar systems on the A 99.
A meeting with the mayor is planned.
But the Autobahn GmbH of the federal government does not want to fuel high hopes.
The communities often receive a rejection.
Most areas are already planned
Even if there are probably hundreds of kilometers of motorway with noise protection walls and embankments: "The areas are actually very limited, often already occupied by another use," says Josef Seebacher, spokesman for Autobahn GmbH for southern Bavaria.
The ramparts, which are mostly only sparsely planted, are nutrient-poor grasslands that are defined as compensation areas.
This means that the motorway authorities have to create an ecological balance for every meter of road that they build somewhere.
According to the State Office for the Environment, the "ecologically superior" areas are intended to "compensate" for the impairments to nature and landscape and must be "permanently secured and preserved".
Sealing them with solar panels is not possible.
Solar panels on noise barriers are also hardly possible.
Static reasons often speak against it, says Seebacher.
In addition, photovoltaic systems reduce noise protection because they reflect the noise, not swallow it.
Another problem: the sun's rays.
As a rule, only motorways in the east-west direction come into question for photovoltaics.
However, the authority does not want to remain completely inactive.
"The southern Bavarian autobahn is considering intensively whether it can at least partially cover its own power consumption - especially the tunnel - at suitable points with its own photovoltaic systems." Specifically, this is initially planned for the half-open tunnel ("Galerie") on the Lindauer Autobahn A 96 near Germering.
The GmbH has now advertised the position of a "technician in the field of photovoltaics": He should plan the system, promote the tenders and manage construction and commissioning.
Advances by the city of Germering, which would have liked to use the areas for solar projects themselves, had previously been drained by the authority.
The A 96 gallery in neighboring Gilching is also to be covered with a solar panel - at the moment both galleries are covered with gravel.
Pilot projects in Ba-Wü and in Switzerland
The southern Bavarian motorway planners are rather skeptical about pilot projects such as those planned in Switzerland and on the A 81 Stuttgart-Singen (near Hegau): solar roofs over the roadway.
"We take a rather critical view of this, since legally it would probably be classified as a tunnel with all the safety equipment that would then be required," says Seebacher.
There are also static problems - for example with snow loads.
In Switzerland, in the Valais, the Servipier company is tinkering with the idea of covering a 1.6-kilometer section of the A6 motorway near Fully with solar cells.
So far, this has failed because of the financing.
For this reason, Germany's first solar roof over a motorway near Hegau, which was announced last year by the Federal Ministry of Transport, is likely to be rather small: the roof area should span just 17 meters of motorway.