A few years ago, I touched on the subject of solar roadways. The concept has gotten quite a bit of attention from the general public, mostly due to slick marketing. It’s actually a terrible idea. There’s really no more expensive way to pave a road, and, if you are going to have solar cells, you won’t find a much worse place for them than on the ground, potentially shaded and not tilted toward the sun. Beyond that, the solar cells are exposed to moisture, dirt, grime, vibration and pressure. The surface needs to be covered with some kind of super-durable transparent material, but aside from possibly synthetic diamond, all potential transparent substances will scratch and scuff with time.
Despite all these issues, one has finally been built. Technically, it’s not a road but a bike path. It is however, a start. A start to what, I’m not sure.
Netherlands unveils world’s first solar bike lane
The world’s first cycle lane made from solar cells produces enough energy to power three households.
Installed in Krommenie, 25 kilometres from Amsterdam, the pilot project is 70 metres long, and will be extended to 100 metres by 2016.
The bike path is made from rectangular concrete modules that contain solar cells, and is encased in a one-inch thick layer of glass strong enough to withstand a truck.
It is capable of producing enough energy to power three homes, though is 30% less efficient than roof-mounted solar panels, as these can be aligned to the sun.
Due to be officially launched on 12 November, the project has so far cost €1.5 million euros, though will ultimately cost up to €3 million once finalised.
Dr Sten de Wit from SolaRoad, the consortium behind the project, envisages that solar roads could eventually be used to power the electric vehicles that use them.
“Electric vehicles are on the rise, but are not really a substitute until the electricity they use is generated in a sustainable way. Roads can generate power right where it is needed,” de Wit explains in a publication for the contract research organisation TNO.
“Sensors gathering information about traffic circulation can help improve traffic management, or even allow automatic vehicle guidance,” de Wit added.
A couple in the United States is currently raising funds for a solar-powered road project. Julie and Scott Brusaw predict that if every US highway incorporated solar technology, the country would generate three times as much electricity as it currently consumes.
The catch? The technology is also three times more expensive to install.
Only there times the cost? Standard solar power may be expensive, but it is not *that* expensive.
The article states that the path can power three households. That’s a terrible way of benchmarking power output, because a “household” can consume anywhere from almost zero watts to several kilowatts, depending on what is being operated. From what I have seen, however, it is often used to mean kilowatts, where one kilowatt is presumed to be the approximate electricity consumption of a household.
If that is the case, this has a peak output of three kilowatts. That, of course, would be nameplate capacity, and almost never reached. The path might come close to three kilowatts, but it will often be much less and at night will be approximately zero kilowatts. For comparison, this is about the power output of the engine on a riding lawnmower. It’s enough to operate a singe laundromat dryer.