By Kyra McCreery
What if our houses were powered by roads?


Bikers in Krommenie, Netherlands, traverse over a bike path capable of powering houses.


Travel to the Dutch town of Krommenie to experience great food, picturesque scenery, and historic landmarks. But the town also offers something that cannot be found anywhere else in the Netherlands, and in only a few other locations around the globe.
     The town is home to the SolaRoad, a bike path capable of powering three houses by harnessing the sun’s energy. Elise Boer is a Krommenie resident and resides in the home powered by the bike path. She bikes over the SolaRoad every day as part of her route to work. “My bike route does more for me than provide a safe way to reach my destination,” Boer jokes. As an environmental engineer herself, Boer is thrilled to see the concept of solar paneled roadways taking hold. “I hardly notice a difference between concrete and the SolaRoad solar cells when I bike to work,” states Boer, “but this concept certainly has the potential to make a difference in how we meet the world’s energy demands.” Boer works with the Hemweg Power Plant in Amsterdam, developing ways to reduce the plant’s harmful emissions and improve its  efficiency. Not thirty minutes from Krommenie’s SolaRoad, the plant churns out enough electricity to power 750,000 homes a year, a stark contrast to the SolaRoad’s three.
     The electricity produced by the Hemweg plant comes at a price that far outweighs its energy output, however. The plant runs mostly on natural gas and coal, which are two of the three types of fossil fuels. Most which are two of the three types of fossil fuels. Most power plant work by burning fossil fuels (either coal, oil, or natural gas) to generate the heat needed to produce steam, which then turns the blades of a turbine attached to an electric generator that makes electricity (“How Power Plants Work”) .
      Although this system is capable of producing large amounts of electricity, burning fossil fuels is quite consequential for a plethora of reasons. The burning of fossil fuels emits a variety of greenhouse gases, namely carbon dioxide, that interfere negatively with the environment, instigating massive issues like global warming and air pollution. These issues, though severe themselves, are the catalysts for many other problems, ranging from an increase in lung disease to acid rain. “We must begin to move now toward the era beyond fossil fuel…” explains climate change activist and professor James Hansen, “The stakes, for all life on the planet, surpass those of any previous crisis” (Hansen et al).
     Our dependence on fossil fuels is also frightening for another reason: fossil fuels will eventually run out. As  the name suggests, fossil fuels are as old as fossils. They are the remains of the plants and animals of an era that occurred hundreds of millions of years ago. Once we have burned all of the fossil fuels, they are permanently gone. The rate  of fossil fuels depletion is increasing as the population grows and the world industrializes.

We’re in the Driver’s Seat
The prognosis for the world if we continue burning fossil fuels at this rapid rate is not good. Many experts warn the CO2 levels in the atmosphere are already exceeding the safe amount.
     Fortunately, we have developed other methods of generating electricity with little to no impact on the environment. Like Krommenie’s SolaRoad, these methods, called renewable energy, produce electricity by harnessing the power of energy sources that are replaced naturally.
     Switching to renewable energy sources in the near future is necessary to avoid the worst consequences of burning fossil fuels. The call to action is urgent, and renewable energy is the answer to the call. Within renewable energy, some experts believe that the sun holds the greatest promise as the world’s future energy provider. After all, the sunlight that falls on the United States alone in one day contains more than twice the energy the world consumes in a year.
     Recently, the concept of solar-powered roadways has been explored by scientists and engineers. The first test of the concept was Krommenie’s SolaRoad, which was constructed in November 2014. Since then, other individuals and companies have jumped on the bandwagon, coming up with their own ideas and innovations related to the technology, but solar roadways are still a ways off from becoming a global reality.
Year fossil fuels reserves will become
fully depleted, according to one estimate.
Percentage of the world that uses non-renewable
energy sources (fossil fuel power and nuclear power).
A Worldwide Focus

            The solar road concept has intrigued plenty of attention across the globe in recent years. The focus was sparked by the installation of the test solar bike path SolaRoad. Built by a consortium consisting of Netherlands Organisation for Applied Scientific Research (TNO), Imtech, and Ooms Civiel, the bike path has been in operation for over a year now andis performing better than expected by even the designers. “We did not expect a yield as high as this so quickly,” said SolaRoad spokesman Sten de Wit. The road generated over 9,800 kWh (kilowatt-hours) of energy in its first year and is expected to pay for itself within 15 years. Though the innovative bike path was designed only as a trial, SolaRoad is pleased with the outcome and is encouraging others to explore the technology.
            One such company in the US also exploring the technology is Solar Roadways, founded by Scott and Julie Brusaw in 2006. Their company has received national attention, and even a grant from the United States government. The company’s idea is to replace all of the asphalt and concrete in paved surfaces in the US
with super strong glass that contains solar panels. By doing so, the United States would have no lack of space for solar cells producing environmentally friendly energy. The panels have an 18.5% efficiency rate, so assuming that they covered the estimated 30,000 square miles of paved surfaces in the contiguous US (roads, parking lots, driveways, playgrounds, bike paths, sidewalks), we could generate more than three times the amount of electricity the US uses in a year every year, and in doing so, reduce greenhouse gas emissions by up to 75%. The panels are also designed to offer extra features such as their own LED lighting to improve driver safety and a heating system to melt snow so that the panels can generate electricity even during cold temperatures.
     The newest solar road installation also happens to be the one with the largest actual impact on society. In early 2016, France reported that 621 miles of road in the country were to be paved with solar panels over the course of 5 years, with the objective of providing energy to 5 million people. The French road-building company Colas and the National Institute of Solar Energy are joining forces to build the roads, dubbed “the Wattway”.
     “The company spent the last five years developing solar panels that are only about a quarter of an inch thick and are hardy enough to stand up to heavy highway traffic without breaking or making the roads even more slippery,” reports David Rogers for Global Construction Review. The panels also differ from the SolaRoad or Solar Roadways’ mission because  they are able to be installed on top of France’s preexisting roads. This feature decreases the cost and difficulty of the installation.
Careful design went into ensuring the panels can withstand temperature and weather changes, and, of course, the weight of thousands of vehicles every day. “At Chambery and Grenoble, was tested successfully on Wattway a cycle of 1 million vehicles, or 20 years of normal traffic on a road, and the surface does not move,” states Colas CEO Herve Le Bouc. The French government is committed to providing cheap, renewable energy, and hopes the Wattway helps do so.

Solar Skepticism

          The benefits of solar roadways do come at a cost high enough to cause many experts to become hesitant about them. For one, the financial price of solar roads is a steep one. Krommenie’s SolaRoad received 3.5 million Euros (approximately $3.82 million) to cover its costs, and the path is only 230 feet long.  And the rough calculations performed by Solar Roadways put the cost of replacing all roadways with their panels at $56 trillion – practically 20 times the federal budget. But Solar Roadways believes the panels will pay for themselves within 22 years, as the roads would cut electricity costs. The company is also exploring with other techniques to generate income using the road, such as paid advertising using the LED light system.
            Money is not the only issue in need of being tackled by these solar companies. Safety concerns must be addressed, especially when it comes to busy roads traversed by thousands daily. The SolaRoad experienced some issues with the protective glass over the panels peeling due to temperature fluctuations, which posed a safety and financial concern. The SolaRoad peeling issue demonstrates that the technology is not quite ready to be used worldwide, but that wasn’t the company’s intention this early on. The road is still in its pilot period, so minor issues were to be expected. Since the issue occurred, an improved coating has been developed and applied, and 300,000 more cyclists have safely used the path.
            Solar Roadways will also need to have its design tested extensively to ensure that it is safe. In a university lab, Solar Roadways is said to have tested the textured glass surface of its panels with vehicles traveling 80 mph to observe how the vehicles fared under different conditions, including rain. But approval from federal highway authorities is much more challenging to receive than a university lab. US Department of Transportation’s Eric Weaver explains that the Department of Transportaion must perform several more rounds of testing on the panels before making any decisions. “We can’t say that it would be safe for roadway vehicular traffic,” he says, “Furthur field-traffic evaluation is needed to determine safety and durability performance.’
            The Wattway had to undergo many rounds of safety testing before getting to the building stage. The Wattway panels have been cleared for safety, but if an issue crops up, the roads and technology could be in jeopardy. Experts are confident, however, that the Wattway will hold up to the task, considering its success in numerous safety checks. 
            Solar roads are also thought to be not as efficient as their rooftop counterparts. Rooftop solar panels can be placed at the best angle for maximum sun exposure, and remain unblocked for all daytime hours. Solar panels on roads have only one angle: parallel to the ground, and are blocked momentarily by every car, bike, and pedestrian that crosses them.
Experts say that, despite these drawbacks, solar roads will still be capable of producing all of the energy we need and more. Plus, solar technology is constantly improving and solar roads are still a relatively new concept. With time, solar road technology is predicted to become more refined and cost-effective.
Engineers, like Elise Boer, agree that time is necessary to allow new ideas to unfold. Boer is confident that solar road technology will make a lasting impact on the world in time. From the opening of the SolaRoad in her home town of Krommenie just over a year ago, to the massive undertaking of the Wattway in France only months ago, solar roads have already begun leaving their impact . “I know that the technology is not ready on a global scale yet, but I think we can get there,” Boer says, “After all, the Wright Brothers were deemed crazy for trying to fly, and they invented the concept of aviation.” •