This week, in the Amsterdam suburb of Krommenie, a little stretch of bikeway officially opened to the public. It’s not all that long—not even three-quarters the length of an American football field—but it is perhaps a glimpse into the future for a country that has almost 22,000 miles of bike trails.
Instead of a conventional surface, the path is constructed of huge Lego-like modules embedded in concrete. The modules are covered with a layer of glass that is coated with a rough plastic to keep bikes from slipping. Inside are rows of silicon solar cells. Together those cells transform this strip of bike path into one large solar panel that plugs directly into the power grid. Engineers estimate that by the time it's extended another 30 yards, an improvement to be completed by 2016, it will be able to generate enough energy to power three homes.
That may not sound like much, particularly considering that this trial trail, known as SolaRoad, cost about $3.7 million. That’s a lot of money for not a lot of road. But a partnership of the local government and a group of Dutch companies was happy to pony up with the hope that they can start building excitement for the concept of solar roads.
Sten de Wit, a scientist at the TNO research institute in the Netherlands, contends that even though these solar panels are about 30 percent less efficient than ones you’d put on your roof, because they can’t be angled to follow the sun, they have the potential to be used on 20 percent of the country’s roads. And that, the experts say, could end up powering traffic lights, street lamps and perhaps even electric cars.
The idea’s boosters also point out that solar costs will continue to drop and that solar cells in roads could push energy into the power grid more efficiently than rooftop panels. While solar roofs need to connect to the grid one house at a time, a roadway makes for one long unit. Plus, roads are much closer to where people live than most power plants. Engineers will spend the next three years gathering data to see if they really are on to something.
My way on the highway
Here in the United States, a couple in Idaho, Scott and Julie Brusaw, will be paying close attention to how the Dutch experiment plays out. They’ve been pretty much obsessed with solar roadways for almost a decade now, only they’re thinking even bigger. Their dream is to someday see all the asphalt and concrete highways in America replaced with roads containing solar cells.
Scott Brusaw, an electrical engineer, says this vision has resulted in quite a few people suggesting that the two of them are daft. He’s heard the same questions over and over. How could a tractor trailer not crack a road of glass? And how could it keep from sliding all over the place? How could the road possibly stay clean enough to let the sun reach the solar cells inside? And just how much would this crazy idea cost?
But Brusaw stuck with it, testing different materials and refining his product. Five years ago the Federal Highway Administration was intrigued enough to give him the first of two rounds of funding, including a grant for $750,000. Since then, he’s been upgrading his solar road concept, adding LEDs that light up a road’s white lines when the panels sense a vehicle approaching as well as the capability to melt snow and ice.
He also says his solar roadway has passed load testing for vehicles weighing up to 125 tons and that its textured surface enables a car traveling 80 miles an hour to stop within the required distance. That said, the only large surface where his solar road panels are functioning is a small parking lot Brusaw built next to his own barn. So far, the Department of Transportation has not signed off on the surface as being safe for vehicles.
Earlier this year, though, the Brusaws got a boost from the public. The inventors set a goal of raising $1 million on the crowdfunding site Indiegogo. Not only was their pitch video viewed almost 250,000 times, but they ended up with pledges totaling more than $2.2 million, a response Scott Brusaw described as “humbling.”
The attention also stirred up the skeptics. One article described the idea as “completely impractical,” “expensive” and a project that would “never, ever get funded” by state and local governments. The writer, Joel Anderson, concluded that there are far better ways to spend your money than investing in “this couple’s hobby.”
The Brusaws plan to start production on their solar panels by the end of the year and then roll out some pilot projects in the town of Sandpoint, Idaho—some downtown sidewalks, part of an airport tarmac—and perhaps a casino parking lot on a nearby reservation.
That’s a long, long way from replacing America’s asphalt highways, but it’s a start, just like the 75 yards of bike path near Amsterdam.