The Netherlands has a solar road, and now France and the U.S. want one. In 2014 in the Dutch town of Krommenie, north of Amsterdam, engineers began laying down shatterproof glass-coated solar panels on a 70-meter bike path that now generates 3,000-kilowatt hours, which is enough electricity to power a small household for a year.
The road is also strong; it supports 12-ton trucks without incurring and damage, including deep skids or grooves.
Electricity from the road helps to light it, can be used to melt ice and snow, and it also provide overflow energy for elsewhere.
The standard output from the technology from road maker SolaRoad is 70 kwh per square meter per year. The prefabricated slabs are concrete modules of 2.5 by 3.5 meters with a translucent top layer of 1-cm-thick tempered glass filled with crystalline silicon solar cells that feed electricity into street lighting or a central grid. Each panel is expected to last 20 years.
International Adoption of Solar Roads
Seeing this accomplishment, the French government is budgeting to pave 621 miles of road with solar panels, so that within five years, electrical energy from the road can be provided to five million people.
The company Solar Roadways provides hope for the U.S. ambitions to also have solar roads. In November 2015, it received a $750,000 two-year SBIR (Small Business Innovative Research) contract from the U.S. Department of Transportation, and the work done so far has proved the panels’ viability.
Results of studies of the four-square-foot full-sized panels (the company has different sizes) showed that 52397-watt hours came from four hexagon panels over a six-month period. Multiply that by 15,840 panels, and the road would produce 414.984-megawatt hours per year per lane mile, factoring in an estimate of 69% solar cell coverage. With 100% coverage, the output would be 601.426-megawatt hours per year per lane mile.
This is good news considering that most U.S. states do not have the budget to cover road repairs, let alone lay down a new road. Such technology could offer a solution. The company is also factoring in new ways to harness the electricity output through cable corridors that might replace utility wires. The idea, that could reduce power outages from downed lines, is to lay corridors by the road with two sections: one for electric cables and one for passage of water.
According to Solar Roadways, their panels meet or exceed the safety characteristics of existing pavement systems. The public appears convinced, given that, in addition to the SBIR funding, the company has raised $2.2 million through its own crowdfunding efforts and is putting some of the funds towards hiring people for new jobs.