China, France Take the Lead as Solar Roadways Concept Spreads

Developers and designers on at least three continents are continuing to chase the concept or the grail of solar roadways, in which solar-electric panels embedded in roads, sidewalks, or driveways generate electricity, provide roadway signage, and solve many of the other problems that make life a challenge for roadway maintenance and operations professionals.

While solar roadways are still limited to small installations and test beds, the sense of potential they create is powerful enough that the research, development, and field-testing continue, with at least one U.S. developer receiving expressions of interest from around the world.

IBTTA members first heard about solar roadways in April 2014, when Walt Arnason of the E-470 Public Highway Authority aired a video on the concept at the 2014 Maintenance and Roadway Operations Workshop in Jersey City, NJ. And, again in June of 2018, with a presentation by Allie Kelly, Executive Director of The Ray, on their testing in Georgia. Now the latest major news report on solar roadways comes from China, where Shandong Pavenergy is testing embedded solar panels on a curved highway carrying “huge log carriers and oil tankers” near Jinan.

U.S. Developer Lags While China Leads

Conventional wisdom in the U.S. has it that solar roadways still aren’t ready for prime time. And the Sandpoint, Idaho company that produced the video behind Arnason’s presentation—after creating a stir with a successful, multi-million-dollar crowdfunding campaign—is still scrambling a bit to find international partners, after its planned demonstration along a stretch of Missouri’s Route 66 fell through.

But in China, Shandong Pavenergy Chair Li Wu sees the highway test as a marker for something bigger. “If it can pass this test, it can fit all conditions,” he told the New York Times. And if it reaches that point, all manner of possibilities come into play.

“The potential appeal of solar roads—modified solar panels that are installed in place of asphalt—is clear,” the Times notes. “Generating electricity from highways and streets, rather than in fields and deserts packed with solar panels, could conserve a lot of land. Those advantages are particularly important in a place like China, a heavily populated country where demand for energy has risen rapidly.”

Generating electricity on the roads that run around and through cities would reduce transmission line losses, eliminate land acquisition costs for more remote solar farms, and—of particular interest to highway operators—cut maintenance costs, by replacing asphalt with more durable solar panels.

And “solar roads could also change the driving experience,” the Times notes, echoing some of the advantages that caught the attention of conference participants four years ago. “Electric heating strips can melt snow that falls on them. Light-emitting diodes embedded in the surface can provide illuminated signage to direct drivers to exits and alert them to construction and other traffic hazards.”

The Idea That Just Won’t Quit

While it hasn’t hit commercial critical mass, the solar roadways concept just keeps on cropping up. In a mid-April post, Inhabit identifies a half-dozen projects under way.

In addition to Shandong and Solar Roadways, the list includes:

• A kilometre-long stretch in Tourouvre-au-Perche, France, equipped with 2,880 Wattway panels from Colas Group, a major construction engineering firm;

• A Wattway installation along The Ray, an 18-mile model highway in rural Georgia described as a “living laboratory testing renewable technologies”;

• A solar-powered bike path in Krommenie, Netherlands;

• A solar sidewalk in Budapest, intended to help charge electric vehicles.

The diversity of concepts underscores a point the Sandpoint-based Solar Roadways made in a recent Facebook exchange with one of its supporters.

“Can we ever expect solar roadways to be used for major highways?” asked Andrew Mumford. “My Michigan roads are in dire need of an upgrade.”

“Yes, eventually,” Solar Roadways replied. “But we've always planned that highways will be our very last application” (notwithstanding their interest at one point in the Missouri 66 project).

“We need to first tackle easier things like driveways, parking lots, patios, playgrounds, and bike paths. Once we are sure all is well there, we'll work hand in hand with the DOT and begin on residential roads, then larger roads, and then finally highways! As we travel we see the bad state so many are in, and we are so anxious to be able to offer a pothole-free, modular alternative.”

Find out about highway innovations around the world! Register today for IBTTA’s Global Tolling Summit, September 5-7, 2018 in Salzburg, Austria.