Bankset / YouTube
Remember solar freakin' roadways, where solar panels were embedded in roads? I thought it was the worst transportation idea ever until Elon Musk's Boring Company came along—the only place dumber for solar panels than in a roadway was under my basement floor. Although, now I would say putting solar panels in Musk's tunnels is worse.
The idea of the solar roadway is seductive because there is all this real estate just sitting there in the sun, and there will someday be a lot of electric cars that will need charging. But there is another kind of road—the railroad—that might be a much better place for solar panels. And that's what is happening in Germany, where the British company Bankset Energy is apparently installing solar panels between the rails of Deutsche Bahn or German Rail.
I use the word "apparently" because there has been talk of this since 2014. However, there are recent photos by Steve Przybilla showing it being tested at a train station in Saxony. According to oft-repeated sources, "100 kilowatts of electricity can be generated per kilometer of railway line. Since the DB rail network is over 60,000 kilometers long, the power that can be generated is comparable to the output of five nuclear power plants." Marc Isoti of Bankset noted in a 2019 post in Railway Technology that their system could be directly connected to the overhead wires and supply power directly to the trains: “Demand for traction power on the world’s rail networks is escalating.”
In addition, solar PV arrays typically output DC power at 600–800V, while electric rail operates at 750V, meaning that the cost of connecting solar generation to DC traction networks—such as those seen in urban rail networks throughout the United Kingdom—should be competitive with grid connection costs, potentially eradicating the need for public subsidies.
“We currently supply power to overhead lines in all current options – AC and DC, low, medium and high voltage, HVDC – to train stations, and directly to the consumer and buildings alongside long-distance rail lines,” explained Isoti.
Bankset / Linkedin
It is hard to verify all of this because the original story by Przybilla is seriously paywalled and none of the web pages associated with Bankset are loading at the time of writing. After an article was published in 2021 about solar railways, Bankset founder Patrick Buri wrote on LinkedIn: "Hello everyone Bankset is the inventor and company behind solar for the railway , for years we test and build solar for the rails infrastructure and we have systems for 16,7 Hz feeds and or 50 Hz feeds live on going in Germany, Austria, Switzerland , Uk, Japan, Italy, China and Australia. Its been tested up side down for years and a proven product up and running great .!"
Solar ties in plan. Bankset / YouTube
There is also a powerpoint deck on YouTube with lots of drawings, photos, and photomontages, but be sure to turn off the sound—it is just very loud music. Bankset isn't the only company trying this; Greenrail in Milan has produced a recycled plastic sleeper that has integrated photovoltaics. According to Solar Impulse, "Each kilometer of Greenrail’s solar sleepers can produce 35 MWh per kilometer, enough power to sustain 10 households’ annual electricity needs. Considering there are approximately 380 million concrete sleepers in Europe alone, the potential could be huge."
So why is putting solar panels in a railway better than a roadway?
- Trains generally stay on the rails, so there is no need to have solar panels designed to take any serious load. Although there is a serious amount of vibration; if someone tried this on Canadian railways, the panels would probably shake apart because the tracks are so bad.
- Railways usually own their rights-of-way and restrict access, so they have much better control. they also own the electrical infrastructure, which is right overhead and can directly use the electricity.
- We have noted before that German railways have been trying to justify hydrogen-powered trains because it was too expensive to electrify many of their lines; turning their rail beds into power sources might change the economics.
On the other hand, rail rights-of-way are generally a lot wider than just the track; it might make more sense to mount the panels next to the track, angled and pointing in the optimum direction instead of lying flat. Deutsche Bahn is already a huge consumer of solar power from more conventional installations.
But still, a solar freakin' railway makes sense in a way the solar freakin' roadway never did.