Imagining a better road
An Idaho couple dreams up a sun-powered super-highwayBy Joan Melcher
Imagine a world where your highway is always clear of ice and snow, it lights up to alert you of obstacles in the road, allows for conduit space for your cable, phone and high-speed Internet, and — oh yeah — provides the electricity for your home.
A husband/wife team in Idaho conjured up the Solar Roadway several years ago. They imagined an “electric road made out of solar panels” — a three-ply surface with specially engineered glass on top embedded with LED lights, a middle layer containing the solar panel a microprocessor, sensors and heating elements, and a base layer to provide space for connecting utility coils. Solar energy gathered in the road would be sent to nearby homes and businesses, eliminating the need for long-distance transmission and power lines.
Nearly a million people have viewed this video where Brusaw explains his vision on YouTube.
Early on, Scott and Julie Brusaw’s idea was to develop a green technology to help wean the country off fossil fuel. But when they presented the idea to the U.S. Department of Transportation, they were told the government was looking for ideas for an ‘intelligent’ roadway that could allow for tracking loads in real time — such as nuclear fuel roads and other hazardous materials — and pay for itself over time. The potential for intelligence in the solar road was what they were looking to fund.
Brusaw shifted gears. What followed was a $100,000 contract from the Federal Highway Administration and Solar Roadway’s win of the popular vote in General Electric’s Ecomagination Challenge, which garnered $50,000. Those funds allowed him to produce a solar road prototype.
Today, Brusaw, who works from a lab near his home in Sagle, Idaho, is preparing for receipt of a $750,000 contract from FHA for the second phase of his work. He plans to build a 12x by 36x strip of road to determine how warm the surface needs to be to prevent freezing, assess how the glass surface works, and test efficiencies of three different solar PV technologies — crystalline silicon, amorphous silicon and thin-film cadmium.
The first questions to emerge when people hear of this idea are: how can a glass surface survive the weight and heavy usage of an 18-wheeler and aren’t the costs prohibitive?
Brusaw answers that glass can be made that is nonslip and as strong as steel and that a one-mile section of single highway is likely to cost around $4.4 million — at least to begin with. But, he says, you have to consider the cost of asphalt roads. “A lot of people don’t realize we have a federal highway trust fund,” he said. “You’re paying x amount at the gas pump into this fund. But the fund went bankrupt a few years ago. No one can afford roads anymore because they’re oil-based.”
He estimates a solar highway is about three times more expensive than asphalt, but that it will pay for itself in twenty years, eliminate power outages, end the need for overhead power lines, and reduce the country’s carbon footprint by about half.
“Think of this long term,” he said. “Take the cost of asphalt, throw in the cost of coal plants, distribution, power poles, snow removal, pothole repairs, painting lines on the road. You have to factor all these in to maintain an asphalt road.”
He estimates one of the solar panels can generate around 7,600Whr of electricity daily and a typical four-lane highway could produced 13.37MWhr per mile, based on four hours of sunlight daily. Extrapolating from these figures, he arrives at an estimate that making all U.S. highways solar roadways would result in about three times the electricity the country consumed in 2009.
The plans now are to start small, using the solar road for driveways, bike paths, patios and parking lots, Brusaw said. One concept is that a large retail outlet such as Wal-Mart could make all its parking lots solar roadways. Electricity could be used to power the store and the electric car recharging stations could be built into the system to allow customers to recharge while shopping.
Another idea is to implement solar roadways in individual homes, using it for sidewalks, driveways, play areas and parking lots while providing electricity for the residence. Brusaw entered the Solar Roadway Home Application in this years Ecomagination Challenge and is again leading in the popular vote.
Asked if aiming at the residential market might be more realistic for the technology, Brusaw said, “We get a lot of requests from homeowners who want to do their driveways, but the ultimate goal is to go on the highway. We need to perfect the technology. We’ll be starting small either way.”
About Joan Melcher
Joan Melcher is a freelance journalist who writes about energy and the environment. She lives in Missoula, Mont.