(Image credit: Dino ahmad ali)
I have no idea if this is even possible, but I remember wondering where all the solar panels would go if we were to convert our cities into running as much as possible on solar power. I realized that most cities are covered with many square kilometres worth of roads, and then I thought, wouldn’t it be nice if these roads could do double duty?
The idea is basically to figure out a way to convert existing road space into solar generators (while still allowing cars to drive on it). The material used would have to be affordable, but it wouldn’t need to be ultra-efficient (large amount of area, but low amount of efficiency would still lead to a lot of energy captured). Alternatively, the system could be based on capturing heat from the road (much of which would come from the son, but some would come from the cars on the road itself).
One advantage of using roads is that they are regularly upgraded and maintained, so you could eventually convert all of the roads over time through this maintenance, as opposed to having to install solar panels in new locations.
Two obvious questions: How much of the energy generated would dissipate before it could be used? How durable would this theoretical material have to be?
Anonymous says:
That’s a pretty neat idea. I think there are issues with durability – roads get a tonne of punishment – there’s a reason why they need maintaining so much. If I recall correctly, the recommendation is about 25% of the city surface area be dedicated to communications (roads, pavements, etc). That’s a lot of surface.
But why not simply use roofs? If there are aesthetic issues – well, I’m sure someone could find a way to make them look more interesting, featured, etc, or we would just get used to it.
But when you mentioned roads, I thought of piezo-electric strips (if that is the right name). I’m thinking of a device that contains two strips of metal and create a current when they are flexed. Now, put that into a road surface, and I bet you could get a current. We see cables running across roads now where they have speed sensors, for example, and I bet you could put these devices into cables. I’m sure there are a tonne of technical complications, but it would be very, very interesting to do something like this.
Wonder if I can get my science department to experiment with something like this?
Another thing I’ve seen (probably on TED somewhere) was current generating glass – which basically turns your solar panelling invisible. Now THAT would also be incredible to see in place – imagine those tall, glass covered skyscrapers also being power-generators.
Ok, now you’ve got me going. Tall buildings flex in the wind, earth tremors, etc – we’re back to the piezo-electric idea.
May 29, 2013 — 8:52 am
David Wees says:
Using roofs would require expensive retrofits, and roofs are rarely updated during the lifetime of a building (perhaps two or three times at most), and any such updates are usually very expensive. It is less likely that the idea will catch on as quickly as it would with roads, which are routinely upgraded and maintained already.
The critical part of this idea is recognizing that we have an enormous area in cities which could potentially be utilized more efficiently. I had thought about the piezo-electric effect, but I wasn’t sure exactly what that would look like. One thought I had was that the piezo-electric effect would increase the amount of friction experienced by cars on the road, which would mean that we wouldn’t be utilizing a new source of power, but really just inefficiently transfering power from one source (the electricity/gas/hydrogen used to power the car) to another. I might be wrong on my intuition though, there may be energy to recover there, so it is certainly worth investigating.
May 29, 2013 — 11:50 am
Anonymous says:
I wonder, if on top of making the roads solar\heat energy capable,you could also make them porous and channeled to allow for rainwater collection and distribution. If you implemented this on roads with sufficient grade, you could use gravity to run a distributed micro-hydro system. In high mountain areas and areas with little solar energy in the winter months, this could off-set solar energy loss…especially if melting snow-pack that dead-ends in ditches was funneled into the conduit. In areas without sufficient grade, water could still be collected and used for agriculture. I’ve often thought that road building technology needs to be brought into the 21st century with energy collection and anti-pollution measures in mind.
As an aside, did you happen to grow up in the Comox Valley, British Columbia? If so, I think I went to public school with you. I got here by way of one of your comments discussing the merits of Khan Academy on the TED forums. As an aside to an aside, I think Khan Academy could have saved me from the hours of undue stress and moments of utter embarrassment that constituted my public school math experience!
Cheers ~ Mica Strong
September 13, 2013 — 1:55 pm
David Wees says:
Hi Mica,
I did! in fact, I think I recognize your name. Your idea on using roads as micro-hydroelectric power generators pretty interesting. I wonder who is doing research on the next generations of roads.
David
September 13, 2013 — 4:40 pm