Recently I was bombarded with news stories and links to videos about 'Solar Freakin Roadways'. As a believer in the social, cultural and economic power of urban planning as well as anything that slightly makes me think I am living in some utopian star trek-esque future, I found the idea emotionally pleasing. However don't hold your breath. We are probably not going to see them in Perth any time soon.
In case you have no idea what I am referring to by 'Solar Freakin Roadways' it is a concept system to build roads out of individual hexagon shaped plates. Each plate has a hard textured tempered glass top with built in solar panels, LEDs, heating element and a micro processor. The idea is that these plates join together to create a smart, interactive and dynamic road. To learn more about the technology you can watch the video below which went viral and led to the company who created the system raising over $2,000,000 USD via a crowd funding program.
In Perth roads make up roughly 20% of our urban land use. This is a large portion of land to allocate to one (albeit very important) use. This does not mean however, that installing 'Solar Freakin Roadways' is the solution to all our infrastructure ills as may people have been claiming on social media. There are a number of questions that need to be answered first to inform the long term sustainability of solar roads. I have outlined a number of issues below; however, if you have some more issues with the system you can write it in the comments thread below.
How long do the individual panels last for? and how much maintenance will they need? Roads are typically built out of bitumen which is soft and flexible, after all bitumen is a highly viscous material which will not easily crack with constant use. The proposed solar roadway is built out of hard tempered glass which will not give or move. In addition to this our road systems are dirty! They are covered in oil, rubber, dirt, sand, exhaust fumes and more. How will these solar panels be effected by 100,000's of cars and trucks driving over them every day. Would they have to be cleaned? How often are they going to get damaged and when a panel inevitably brakes we will have a somewhat undesirable scenario of broken glass on the road. Will this damage other cars on the road?
Real-world testing and proof of concept? It will require some small controlled studies on a section of road before any diligent decision maker would ever think about scaling it up, which would be at least a few years of study. The current technology presented in the video is no where near the point that it can be scaled up or implemented. This alone would make a mass roll out a further 5 - 10 years from now. It is great that there is investment in this sort of technology and I am sure there will be a lot of great advances that come out of it, however when something sounds too good to be true remember that it normally is. There is still a lot of work on this type of system that needs to be done.
How much is this system going to cost? This is the big one. Early estimates on how much it would cost to cover just the interstate highways throughout the United States puts the figure at $1 trillion. Instead of spending such a large amount of money on implementing this sort of roadway I think we are more likely to see advances in smart cars. Much of the functionally of this road system could be provided by a car which is equipped with sensors and an augmented reality windscreen. In Perth we can not even raise the money to paint bicycle lanes, I doubt we are going to replace our roads with expensive solar panels. Even worse Perth also suffer's from the additional issues of distance and low population density which would drive prices even higher.
We may not get solar roadways however there is a niche market for solar and LED carparks, driveways, sporting facilities and even potential small portions of city centres. One thing I find most interesting when people discuss solar roadways is that there has not been a good case put forward as to why this system is better than other avenues of funding. I am not arguing that we should not be investing in these sorts of technologies, however, it is important to ask the question.
Why should we put solar panels on roads? Why not on the roofs of houses and businesses as we have been doing for a while and has actually been quite successful. Why invest so much in roads? Roads are important however, as we have historically seen, investment in infrastructure creates 'induced demand'. By investing so much in a road system not only are we decreasing the potential for investment in public transport but are also encouraging people to drive on these new, super-cool, tron-like roads. It is fantastic to see so many people getting excited about roadways however that excitement must always be coupled with reality and a sense of pragmatism.