Nine years ago TreeHugger Warren wrote the headline Solar Powered Electric Bicycle. Now We're Talking. It drew sixty comments (a lot at the time) complaining that the wheels were a stupid place to put the photovoltaics. Alas, that bike was vaporware but Eric Jaffe of Citylab points us to today's version, the Solarbike designed by Jesper Frausig in Denmark.
So much has changed in that time. Photovoltaics have got so much better, as have bottle batteries and hub motors. Furthermore, people now know how these things work, that it is charging the battery when it is parked in the sun and discharging when running, not actually being driven by the solar cells. As the designer notes, "The on-wheel solar cells deliver clean energy directly to the battery. While the Solar Bike is standing still, it charges the battery. When it is in motion, the solar cells and the battery provides energy for the motor." (that is different from this one that Mike showed that actually can run on solar power).
Frausig has been working on it for 3 years and built two prototypes, and claims that it has a 70 km (43 mile) range and a maximum speed of 50 km/hr (30 mph) and a standard speed of 15 mph, which sounds safer for a bike.
There is really nothing unusual about the bike itself, just the charging from "shadow optimized" solar and some clever way of getting the electricity from the panels to the frame. But it is nicely packaged, and this video shows a lovely ride through some of Copenhagen's nicer bits of bike infrastructure and a run through the Kalvebod Waves. The video brought back memories; I pedalled much the same route with Mikael Colville-Andersen and Chris Turner.
It has been nominated for the INDEX: Design to improve life Awards, so it's not vaporware; no word on when it is going into production or what it will cost, but I have written the designer and will update if he responds.