After the hubbub that Solar Freakin Roadways caused last year (ranging in tone from hopeful to critical) all seemed to have gone quiet on the potentially revolutionary road surface front. I don’t think anyone expected us to be laying these things down en-masse once the Indiegogo campaign finished but I’ve been surprise that I hadn’t heard more about them in the year that’s gone by. Whilst Solar Roadways might not have been announcing their progress from the rooftops there has been some definitive movement in this space, coming to us from a Dutch company called SolaRoads. Their test track, which was installed some 6 months ago, has proven to be wildly successful which gives a lot of credibility to an idea that some saw as just an elaborate marketing campaign.
The road was constructed alongside a bike path totalling about 70m in length. Over the last 6 months the road has generated some 3,000kWh, a considerable amount of energy given the less than ideal conditions that these panels have found themselves in. Translating this figure into an annual number gives them around 70kWh per square meter per year which might not sound like much, indeed it’s inline with my “worst case” scenario when I first blogged about this last year (putting the payback time at ~15 years or so), but that’s energy that a regular road doesn’t create to offset its own cost of installation.
Like Solar Roadways the SolaRoad’s design is essentially a thick layer of protective glass above the solar panels which are then backed by a layer of rubber and concrete. Instead of the hexagonal tile design they’ve instead gone for flat panels which would appear to be more congruent road design although I’ll be the first to admit I’m not an expert in this field. By all accounts their design has stood the test of time, at least with the light load of cycling (although they claim it could handle a fire truck). The next stage for them would be to do a full scale replica on a road that sees a decent amount of traffic as whilst a cycleway is a good indication of how it will perform there’s nothing better than throwing the challenges of daily traffic volumes at it.
Unfortunately SolaRoad isn’t yet ready to release a potential price per kilometer installed however the entire program, including the research to design the coatings and the road itself, has come up to some $3.7 million euros. Considering that my original estimates pegged a competitive cost at around $1 million per kilometer I’d say that the trial has been a pretty good investment (unless you’d really want 4km worth of road somewhere instead…). That will ultimately be what determines if something like this can become a feasible alternative to our current asphalt road surfaces as the idea won’t get any traction if it’s noticeably more expensive than its traditional counterpart.
It’s good to see progress like this as it shows that the idea has some merit and definitely warrants further investigation. Whilst the power generation numbers might not be revolutionary there’s something to be said for a road that pays itself off over time, especially when that comes in the form of renewable energy. With further advances in grid technology and energy storage these roadways, in conjunction with other renewables, could form the basis of a fossil fuel free future. There’s a long way to go between today and that idyllic future but projects like this ensure that we keep making progress towards it.