It sounds crazy, right? But Scott and Julie Brushaw at Solar Roadways have a working prototype of a solar panel that can withstand the especially harsh conditions of highway road surfaces and produce electricity from the sun at the same time. Solar Roadways have a lot more information on their FAQ, for anyone who's interested, but here's a summary from their Indiegogo campaign:
Solar Roadways is a modular paving system of solar panels that can withstand the heaviest of trucks (250,000 pounds). These Solar Road Panels can be installed on roads, parking lots, driveways, sidewalks, bike paths, playgrounds... literally any surface under the sun. They pay for themselves primarily through the generation of electricity, which can power homes and businesses connected via driveways and parking lots. A nationwide system could produce more clean renewable energy than a country uses as a whole (http://solarroadways.com/numbers.shtml). They have many other features as well, including: heating elements to stay snow/ice free, LEDs to make road lines and signage, and attached Cable Corridor to store and treat stormwater and provide a "home" for power and data cables. EVs will be able to charge with energy from the sun (instead of fossil fuels) from parking lots and driveways and after a roadway system is in place, mutual induction technology will allow for charging while driving.The panels are quite feature-rich, making the national highway system a nearly complete, integrated infrastructure that combines transportation, power generation and distribution, communication networks, and water storage. I would imagine that the panels could also be upgraded to add new features as they're thought up and developed.
It's the kind of distributed application of renewable energy that I've been thinking would come about but just couldn't visualize myself - a new application that fundamentally changes our relationship with energy the way the internet changed the way we communicate. The breadth of possibilities is astonishing, but I would like to focus on one in particular - the interaction of such a roadway with EVs. First, what could such a future look like if every road was paved in solar panels driven on with EVs? And second, what is a feasible way to get there?
A World Paved in Solar Panels
If we ignore how we would achieve such a thing, and imagine for a moment that all of our roads were already filled with solar panels, what would driving be like? ICE cars would certainly be a thing of the past, but EVs would be much different than they are today as well. For one, if cars could get the energy they needed from the road, they wouldn't need much on-board energy storage. (Not to mention how freaking cool it would be to drive on your energy source, powered by the sun.) Batteries could be much smaller than they are now, instead of needing to get larger to increase the car's range.
Take a Nissan Leaf, for example, with its 24 kWh battery pack. It has about 80 miles of range, but how much battery capacity would the car really need if it got nearly all of its energy from the road through inductive charging? Certainly not more than a quarter of its current range would be necessary, but maybe 10 miles or even 5 miles would be sufficient. As the battery capacity drops, so would its weight, reducing the load on the drive motor and making it more efficient.
The battery would also probably be more advanced and thus higher energy density, reducing the weight even further. So would a 1-2 kWh battery be sufficient? A car with such a small battery could charge much faster than today's EVs, and you probably wouldn't have to ever plug it in anyway because it would charge from the road. Of course, it would also be much less expensive as well. Considering that the Leaf's battery likely costs well north of $10,000, such a car would probably cost half of what the Leaf does now.
EVs would not only get energy from the road, but information as well because the panels all have communicating microprocessors in them. It's a smart road, and it would make autonomous vehicles much easier to develop and coordinate than they are now. If every car could communicate with the road and each other, accidents could be all but eliminated, traffic congestion could be substantially reduced, and cars could form highly efficient drafting trains to further reduce energy usage. These are all benefits that could be achieved by autonomous vehicles without a smart road, but with a smart road, the number of sensors needed on the car could be dramatically reduced and the amount and quality of information used to make decisions could be much better.
A self-driving car would also provide the obvious benefit of relieving the driver to do other more productive or enjoyable things. So, a solar road could enable cars that never have to be charged or fueled up, automatically take you safely where you want to go, and cost less than today's dumb cars do. Can I have one now, please?
Getting There From Here
Obviously, we're not going to go from today's asphalt roads and ICE cars to smart solar roads and autonomous EVs overnight, but that's the beauty of this type of technology. Solar panels could easily be added to sections of road, piecemeal at first, and gradually more extensively as the production ramped up and the idea caught on.
Even without inductive charging EVs or autonomous vehicles to take advantage of the most advanced features of the panels, the road would immediately provide substantial benefits in power generation, and all of the other things mentioned above. Installing solar roads would have zero impact on the ICE cars that most people have, and there's no reason why new ICE cars couldn't also take advantage of the sensors and communication abilities of the solar roads and add autonomous features as well. People that needed ICE cars for their range to get between sparsely paneled sections of road wouldn't have to switch to EVs prematurely.
As solar roads became more connected and pervasive, people could move to EVs and the EVs could begin reducing their battery capacity. The transition could be completely incremental, without requiring any drastic shifts in production or forced decommissioning of ICE vehicles. Although, I would imagine when a certain area reached a critical mass of solar roads and autonomous EVs, all of a sudden everyone would switch over, like everyone did with smart phones and flat panel TVs. The benefits would be too great to ignore.
On the production side, factories could be built in a distributed way so that panels could be sourced more locally to where they're needed, creating thousands of new jobs across the country. If all of the roads were to be repaved with solar panels, a lot of factories would be needed to produce all of those panels for quite a long time, and some number of factories would be needed indefinitely for replacing damaged panels and paving new roads. Building that kind of manufacturing infrastructure would give a huge lift to our economy, likely for decades to come.
The possibilities are fascinating to think about. The Interstate Highway System cost about $500 billion in 2014 dollars, took 35 years to build, and completely revolutionized transportation and our economy. A project to pave the nation's roads in smart solar panels would be even larger in scale and would have an even greater impact on our economy's health and vibrancy. Do we have the political and financial will to undertake such an awesome endeavor? I hope so. It will be a total game changer.