Solar roads/pavement implants update – August 2017

A Wattway solar road in Tourouvre, France

Cars are getting smarter—can’t the road get smarter, too? That’s the question Harriet Langford is trying to answer along an 18-mile stretch of Interstate 85 in western Georgia. With grassy medians and large metal signage, the interstate looks like any other, but to Langford, the president of a green highway project known as The Ray, it’s a “living laboratory for technologies that can transform the road.”

It’s also the site of the country’s first solar road, unveiled in December 2016. About 5,400 square feet of solar panels sit atop asphalt as they farm sunlight near the Georgia Visitor Information Center in West Point, off Exit 1. The installation, which can produce 7,000 kilowatt-hours of energy annually, is the result of five years of research culminating in a technology called Wattway. Enclosed within thin layers of protective plastic, the photovoltaic cells help power the Georgia Visitor Information Center.

“There are studies saying that roads are occupied only 5 to 10 percent of the day, and during the rest [they] just lay there under the sun,” says Nicolas Griglio, a development engineer at Wattway.

Wattway solar road installed outside the Georgia Visitor Information Center in West Point

Though small solar roadways are popping up around the globe, including one in Missouri at the Route 66 Welcome Center, the technology is hardly at a scale where it could start replacing the country’s 160,000 miles of interstate. France just kicked off the most ambitious project to date—621 miles of solar roadway—with a 0.6-mile stretch in Normandy that cost a cool $5 million. But still, our 60-year-old highway system could definitely be smarter.

First, however, there are the non-tech fixes our aging infrastructure requires. I’m talking about the basic construction and maintenance of roads, bridges, and ports, funded primarily by a federal gas and diesel sales tax that goes into the Highway Trust Fund. While the cost of maintaining our highways has risen over the years, the gas tax of 18.4 cents per gallon (24.4 cents for diesel) has been the same for almost a quarter-century. At the same time, while fuel economy improvements have reduced pollution, they’ve also lowered the amount of money entering the Fund. That’s why many states this year, including Florida, Georgia, and Pennsylvania, are taking matters into their own hands and increasing state fuel taxes.

President Trump talked a lot about supporting infrastructure projects during his campaign, but the forecast for a $1 trillion plan introduced by Senate Democrats last week doesn’t look sunny. Among many issues is the GOP’s lack of support for clean energy programs.

Even so, as we fix the highways we currently have, we shouldn’t lose sight of what could be down the road. That’s where I-85 comes in. In addition to the solar on the actual road, Georgia Power plans to install along the right-of-way a 1-megawatt solar farm with panels that will feed the grid. The Ray project also showcases a solar-powered charging station for electric vehicles, a tire pressure monitoring system to promote fuel efficiency called WheelRight, a landscaping method known as bioswaling that uses plants to naturally filter road runoff, and a butterfly garden to give roadside biodiversity a boost.

None of this would be possible without a close partnership with the Georgia Department of Transportation. “Everyone at DOT understands the potential significance of the highway,” says Sam Wellborn, the longest-serving board member of the Georgia DOT. “We think in time―and I’m talking 10 to15 years―we are going to become a model of what can be accomplished on our highway system in America and around the world.”

A long-term approach through trial, error, and success is exactly the path Langford foresees for The Ray. There may indeed be cheaper ways to improve road quality and generate carbon-free electricity, but we won’t know without experimentation. That’s part of the beauty of The Ray’s philosophy of testing new technologies in small applications.

Even if the solar road itself doesn’t pan out to be the best option, ideas like this are helping forge new alliances between sectors. “We always thought transportation and electricity production were two different things,” says Tony Dutzik, a senior policy analyst with the Frontier Group. “I think what we are seeing, and solar roads are an example of that, is that there are potential synergies where we didn’t have them before.”

The world definitely needs solutions fast, and hopefully The Ray’s tinkering can help point us in the right direction, says consultant Christopher Kaminker, senior adviser to the bank SEB on matters of climate and sustainable financial solutions. Kaminker believes The Ray is an archetype of the whole-system approach required for thinking globally and acting locally. Through this lens, Georgia’s sustainable highway expands the mandate for roads to include beauty, safety, biodiversity, clean water, renewable energy, and zero emissions. It takes this whole-system approach to financing too, with funding from philanthropic organizations, grants, corporate contributions (in this case, Georgia Power and KIA), and government support.

So can the road get smarter? The answer seems to be yes—though the journey ahead is long, and not necessarily cheap.