The World’s First Solar Bike Path Keeps Bikers Safe, Powers Surrounding Neighborhoods, generates enough power to ultimately be worth it.

One of the next places cities put solar panels could be roads—or bike paths. BY ADELE PETERS, Fast Company, 2014

When cities run out of space for solar panels on rooftops, one of the next places to turn could be roads–or bike paths. In the Netherlands, one of the country’s newest bike paths doubles as a solar energy generator that could eventually help power surrounding neighborhoods.
“In the Netherlands, we have about 140,000 kilometers of roads–enough to go three times around the world, and more. It’s a huge area, more than all of the rooftops combined,” explains Sten de Wit from TNO, the research organization that helped create the new bike path.

“We already put solar panels on rooftops, and this is a process that is going faster and faster,” he says. “But if we look at the goals we have for sustainable energy production we need more area than just rooftops. If we can put panels in a road which is there anyway–then we can get that function and lots of green energy without disturbing the landscape or taking extra space.”

TNO worked with engineers and local government to develop a paving system, called SolaRoad, that could generate power while still holding up to traffic. “If you put a normal solar panel on the road, you’d have two main issues–one would be that it’s slippery especially when wet, and two, it would probably break very quickly,” de Wit says. “Those were the two main challenges we had to solve. It also had to be transparent enough that light could reach the solar cells.”

The new bike path is a pilot, and the researchers will use it to gather all kinds of information, including how much energy this type of road can generate. “Based on what we’ve done in the lab, we think the energy gain will be between 50-70 kilowatt hours per square meter per year,” de Wit explains. A typical Dutch household could be entirely powered by about 50 square meters of roadway.

The pilot path will mostly handle bike traffic, but also the occasional car, and the researchers plan to keep developing the technology for use on regular roads (in a similar way to the U.S.-based Solar Roadways project, which claims that solar roads could power the entire United States).

They also hope to take the technology beyond the Netherlands. “The Netherlands is not the most sunny country in the world,” says de Wit. “So if we go further south, it’s very likely that this product will be at least as interesting there as it is here.”

The technology isn’t cheap–the pilot bike path cost $3.75 million dollars for a narrow stretch of only 230 feet. But as the development progresses, the cost is expected to come down. And since it generates power, it can slowly start to pay for itself.

Adele Peters is a staff writer at Fast Company who focuses on solutions to some of the world’s largest problems, from climate change to homelessness. Previously, she worked with GOOD, BioLite, and the Sustainable Products and Solutions program at UC Berkeley.

Dutch Solar Bike Path SolaRoad Successful & Expanding, Clean Technica, March 2017

March 12th, 2017 by 

Bike paths: The Netherlands is covered with them, connecting more or less every destination a person might wish to go to and greatly increasing the convenience of cycling as a sustainable mode of transport. In the densely populated country, where space is scarce, a consortium of companies and research labs called SolaRoad is endeavoring to make those cycle lanes reduce carbon emissions in yet another way: by having them to generate solar electricity.

In 2014, SolaRoad started its pilot project in the town of Krommenie near Amsterdam by replacing a stretch of 70 meters of a tarmac bike path with solar modules it developed. The embedded solar panels are protected by a 1 cm thick coating, which is highly transparent but does not compromise traction. The project attracted great attention, both inside and outside the Netherlands, and within the first year after the solar bike path opened, 300,000 cyclists and scooters rode over it.

Despite the difficulties paired with embedding solar panels in a road, such as the flat angle in which the modules are positioned, the thick layer of protection glass covering them, and the high numbers of travellers passing over and blocking the sun, the amount of power generated quickly defied expectations. Already half a year after the cycle lane was inaugurated, SolaRoad sent out a press release stating that, with 3000 kWh generated, the solar panels were outperforming the 70 kWh annual per square meter expected threshold set in the lab. In its first year, the SolaRoad produced 9,800 kWh, roughly equivalent to the annual average consumption of three Dutch households.

Gerelateerde afbeelding

To accommodate for testing new modules that incorporate innovations inspired by the first 70 meters of SolaRoad, the project was expanded by 20 meters in October 2016. Some of these modules contain thin-film photovoltaic panels. Furthermore, the coating of the new modules has been improved.

The project near Amsterdam will continue till 2018, with the goal of further development and testing of the SolaRoad modules that convert the sun’s energy to electricity while facilitating bike travel. SolaRoad has meanwhile launched the SolaRoad Kit — 10 meters of solar bike path that can be ordered by companies or governments. The province of Groningen in the northern part of the Netherlands has already bought a kit, which will be in operation in a month from now.

Another interesting development is the announcement of a cooperation with Californian road authority Caltrans and the Dutch province North-Holland to develop a second pilot project in Lebec, Kern County. Since the announcement last March, however, no details on what the project might look like have been revealed.

Although per kWh cost figures are unknown, it is very likely that the electricity produced by the SolaRoad is relatively expensive, especially due to the small scale and novelty of the project. Surely, it cannot compete with normal solar power generation, such as from rooftop solar and solar farms, but the point is that such solar bike paths compete with the cost (and no direct revenue) of conventional bike paths, not other solar installations. As research continuous and enthusiasm coming from many different sides accrues, larger-scale projects could emerge, and we could get a better sense of how viable this idea is. Economies of scale would drive down costs, and suddenly, solar bike paths could no longer be a curiosity.

To reiterate: the SolaRoad does not have to reach cost parity with rooftop or utility-scale solar, but the more solar electricity we can generate via cost-competitive means versus the alternative, the better. If we were to travel a decade or so into the future, most available rooftop space might already be covered. So, to further increase solar generation capacity at that time, either land reserved for agriculture or nature would have to be used, or surfaces such as bike paths could be considered.

In densely populated countries such as the Netherlands, geographers are already warning about the burden large-scale solar power plants could place on land available to other uses. Converting gray tarmac into solar highways would be a logical alternative, provided the cost difference is limited or positive.

SolaRoad is not the only consortium in the world working on this type of project. In the US, Solar Roadways is working on high-tech roads that produce electricity and can, among other things, de-ice themselves. Unfortunately, their prototype in Idaho has suffered from severe technical issues, recently even requiring intervention by firefighters as smoke started to come out of an electricity box on the test site.

Another example is located in France, where a one-kilometer stretch of roadway has been covered by solar panels by construction company Colas. This “Wattway” is the start of a controversial plan to convert a staggering 1,000 kilometers of French streets into solar roads.

Electricity-generating roads haven’t left the experimental phase yet, and are very probably not cost-competitive with conventional roadways at this point. But as the rate of innovation is high, and public enthusiasm big, we shouldn’t be surprised to see more SolaRoads in the coming years, possibly of much larger scales than now deemed feasible.

Looking at the Dutch Solar Bike Path After One Year

By Scott Huntington

Just over a year ago, people from all around the world turned their attention to Krommenie, Netherlands, as it opened a high-tech bike path to travelers.

Dubbed the SolaRoad, the path is special because one of its two lanes is equipped with solar panels that can feed energy back to the grid. Although the path spans less than 250 feet in length, developers hoped it would be able to produce enough annual energy to power homes. Now that it’s been open for a full year, it’s time to look at what worked and what didn’t.

The path passes a major test

After one year, researchers are in an educated position to say whether the SolaRoad was everything green-minded people hoped it would be. Fortunately, the path exceeded expectations even in its early stages. After it had only been operating for six months, the path attracted more than 150,000 riders, and more importantly, generated more than 3,000 kilowatt-hours of energy. That’s enough to power a home for a year.

Testing and improvements are ongoing

As you may have expected due to the pioneering nature of this path, the SolaRoad had some problems despite its impressive results. In fact, a mishap occurred only a month after the SolaRoad was open. Poor weather conditions caused its top layer to break off, and a portion of the path had to be shut down. That happened even though the materials were rigorously tested in a laboratory beforehand to ensure they were roadworthy. This brings up some pretty hefty concerns about how these roads would eventually handle cars, if they were breaking on a bike path.

Eventually, engineers were able to come up with a material that would hold up to the weather, and the SolaRoad opened in entirety again. Because the path is in the middle of a three-year testing cycle, it’s possible other unexpected challenges will arise later on that will need to be dealt with.

solaroadRiders have adapted to the technology well

As mentioned above, more than 150,000 bikers have already chosen to travel over the SolaRoad. Engineers also clarified that riders hardly seem to notice anything different about the path’s surface. As a result, researchers agree the public has smoothly adopted the technology.

It makes sense that the SolaRoad was launched in the Netherlands. Cycling is already a very popular activity there, and it’s known to be very safe.

However, the same can’t be said in terms of bike use in the United States. Statistically, only 1 percent of trips are taken by bicycle. Additionally, there is often confusion about bike laws, and it doesn’t take to see cars driving in the bike lanes, or at least ignoring the often-forgotten law of giving a bicyclist a minimum of three feet of space. It will be interesting to see the reaction if a solar bike path ends up in the U.S.

Energy generation worth a closer look

Initially, the fact that the SolaRoad has generated enough energy to handle a household’s needs in just six months seems impressive. However, some critics have urged people to develop an alternative perspective.

Consider that the SolaRoad cost $3.7 million to build, and in the Netherlands, solar energy costs $2 per kilowatt. That means the money spent for the SolaRoad could have bought 520,000 kilowatts of electricity. Compare that amount with the 3,000 kilowatts produced by the SolaRoad, and it’s easy to see why some people aren’t convinced the project was worthwhile. That’s 173 houses that could have been powered instead of one, for those wondering about the math.

The cost involved and the possible challenges with finding materials that can tolerate certain climates are two possible reasons why solar bike paths may not be poised for widespread adoption just yet. Still, we’re learning a tremendous amount by giving it a shot, and there is hope for the future.

Those of us who live in the states may not have to wait too long to see some Dutch influence. This spring, the Netherlands and California signed an agreement to collaborate on energy-efficiency projects ranging from electric car charging stations, to zero-emission public transit solutions and, yes, maybe even our very own SolaRoad.

Image credits: SolaRoad

Scott Huntington is a writer from Harrisburg who has been featured on Business Insider, INC, Time, and more. Check out his automotive writing at offthethrottle or follow him on Twitter @SMHuntington