"It would become the very first 'zero energy bridge' in the Netherlands. Thanks to Wattway's solar panels Colas, France, in the asphalt construction, the bridge has to provide its own energy, for example for the lighting."
Hmmm, those proven winners are made by French
WATTWAY. Details are in the
WATTWAY® patented resin-film construction and
https://patents.google.com/patent/FR3073106A1/en. Seems to limit them to 60V to elude regulatory and safety but they are frequently wired in series...
The failed solar bike pathway in Erftstadt, Germany seems to also be using those WATTWAY solar panels? The city tossed it back to TÜV-Rheinland.
A problem is there are no (safety) standards for solar roadways yet. I think it ended up being high voltage and grid tie? The electrical fires are a concern.