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December 19, 2019 (LaGrange, GA) — The Ray, the Georgia Department of Transportation (Georgia DOT), and international infrastructure innovator Colas have unveiled an upgraded version of the Wattway solar road at the Visitor Information Center located at Exit 1 on Interstate 85.

Colas invented the Wattway solar road in partnership with the French National Solar Energy Institute. These thin, heavy-duty photovoltaic panels are affixed onto the existing roadway using a patented surface texture that has been designed to provide as much skid resistance as conventional pavement. The Wattway technology enables the road to multi-task: to both provide a surface for safe vehicular traffic, as well as a new land opportunity for generating clean, renewable energy.

Wattway on the section of I-85 referred to as The Ray was originally installed in December 2016. The first year following installation, Wattway was the highest-renewable energy producing pilot project of the 40-pilot projects worldwide, generating 8,420.74 kWh, which is enough energy to drive a single electric vehicle approximately 35,000 miles. It remains the only public, drivable solar road in the United States.

“In partnership with the Georgia Department of Transportation, The Ray is a cutting-edge pioneer in experimenting with innovative technologies that foster user safety and sustainable development. Thanks to high-quality partners like them, Smart Road solutions such as Wattway can progress. We are happy and proud to have The Ray and Georgia DOT among our partners,” said Etienne Gaudin, Wattway Manager.

Since 2016, feedback from The Ray’s I-85 test site has helped Colas to improve installation techniques, the electrical architecture and perfect the patented photovoltaic panel. Wattway has capitalized on this information and developed successive versions of photovoltaic panels that are more resilient and weather resistant, more compact, and more economical. In addition, performance has been improved by 21 percent, reaching 144 Wp (Watt peak) / m².

“We broke the mold with version one in 2016,” said Harriet Anderson Langford, founder and president of The Ray. “I give so much credit to Georgia DOT for working with us to permit something so groundbreaking. What we’ve done today is the obvious next step – innovation in real-time. This new version is better because of The Ray and we’re excited to see how it performs over the next several years.”

“Georgia DOT’s focus on embracing innovative new technologies has driven dynamic new relationships with partners like The Ray and Colas,” said Georgia DOT Commissioner Russell R. McMurry. “We are grateful for the partnership with these two organizations and are delighted that this installation in Georgia has led to even better versions of Wattway that can be deployed around the globe.”

About The Ray

The Ray is a proving ground for the evolving ideas and technologies that will transform the transportation infrastructure of the future, beginning with the corridor of I-85 in Georgia that is named in memory of Ray C. Anderson (1934-2011), a Georgia native who became a captain of industry and was recognized as a leader in green business when he challenged his company, Atlanta-based Interface, Inc., to reimagine the enterprise as a sustainable company—one that would pursue zero environmental footprint. Chaired by Ray’s daughter Harriet Langford, The Ray is an epiphany of the Ray C. Anderson Foundation. Learn more at

About the Georgia Department of Transportation (Georgia DOT)

Georgia Department of Transportation plans, constructs and maintains Georgia’s state and federal highways. We’re involved in bridge, waterway, public transit, rail, general aviation, bike and pedestrian programs. And we help local governments maintain their roads. Georgia DOT and its nearly 4,000 employees are committed to delivering a transportation system focused on innovation, safety, sustainability and mobility. Through a culture of innovation and collaboration, the Department’s vision is to boost Georgia’s competitiveness through leadership in transportation. Learn more at

About Wattway

Wattway is a photovoltaic road surface that is a Colas Group innovation. Heavy duty and able to bear all types of vehicle traffic, Wattway panels are glued directly to the roadway to produce electricity through solar energy. The solution has been rolled out on some 40 trial sites in France and around the world to test the technology and uses in real weather and traffic conditions.