Solar Roadways – A Cautionary Tale About Crowd-Funding Cons

There’s no denying that in general, Kickstarter, Indiegogo and platforms like them have made a big impact on the way that entrepreneurs realise their ideas, and enabled some fantastic products to be mass-produced. 

Unfortunately, (and sometimes hilariously) the open nature of crowd-funding means that anyone can create a campaign for any idea whatsoever. One of the worst, in my view, was Solar Roadways, which became especially concerning because its Indiegogo campaign was actually successful – in fact, it is Indiegogo’s most backed campaign ever, raising 2.2 million dollars.

The idea of the project is to replace all the roads in the US with solar panels featuring LED lighting and snow-melting heaters. The company behind it has received around 1.6 million dollars from the US Department of Transportation in order to help it further its research into its solar road panels.

The problem? They don’t work, they can’t ever work, and they are hideously expensive, at an estimated cost of $56 trillion to replace all US roads. The reasons they won’t work are pretty simple. 

Whilst it’s true that in the lab, solar panels with up to 46% efficiency have been developed, affordable solar panels are horrendously inefficient, converting around 12-18% of the energy they receive from the sun into electrical energy. 

This power then has to be inverted to be fed into the grid, and inversion is not particularly efficient either, ranging from 50-90% efficiency. As a charitable estimate, Solar Roadways would be around 10% efficient… if the sun were shining at full brightness directly above the panels, and the glass was completely transparent.

For the glass used by these panels to be durable enough to be run over by trucks, it will have to be very thick. In fact, the maximum weight of an 18-wheeler truck is 80,000 pounds (36,000 kg). This means that each wheel will exert around 20000N of force. 

The area of a Solar Roadways panel is 4.39 square feet, which makes it roughly equivalent in area to a 60 cm2 panel. If we assume that each panel will need to support 2 wheels at a time, we’re looking at tempered glass around 3 cm thick. This sort of glass is incredibly expensive, not to mention optically poor.

It will also have to be uneven enough in texture to provide grip for vehicles, which will refract light wastefully, not to mention that it will have to be cleaned far more than an asphalt road in order to maintain any transparency at all. 

Add to this that the panels cannot track the sun, which can add up to 32% efficiency. Another nail in the coffin is the fact that usually, there are cars on the road, blocking the sun. The only installations of Solar Roadways panels so far have been on car parks – but surely a parked car just wastes the energy that could have been collected if the panels were somewhere else?

What’s more, think of how much power the LED lighting and heaters will require. Bearing in mind that LEDs and heating elements take up space that could have been used for photovoltaic cells, think how many LEDs would be required to produce light visible through 3 cm thick glass at midday; it would probably be a full panel of LEDs. 

Equally, heating elements would have to get up to such a high temperature to melt snow off the panels through the glass that they would damage the delicate photovoltaic cells. The other issue with this is that when snow has fallen on the panel, it can’t generate any power, so the heaters would have to use energy from the grid anyway.

The eventual efficiency of Solar Roadways can only be determined by testing, but I would estimate that they will be 2% efficient or less.

Let’s look at a comparable installation of solar panels that already exists: the SolaRoad cycle path in the Netherlands. SolaRoad is just 83 metres long (following expansion from 72 metres in October 2016) and has a glass top layer with epoxy reinforcement that is around 1 cm thick.

According to an EU report, the price in the Netherlands for wholesale electricity is €52/MWh. In one year, SolaRoad generated 9.8 MWh of electricity, which is worth around €510. 

At a total project cost of €3.5 million, SolaRoad will take at least 6,868 years to pay for itself (and the research involved in creating it), and given that after one year of operation, the top surface was in such poor condition that it had to be replaced (even though the stress placed upon the surface by cyclists is minuscule), it is likely to be far longer. 

Of course, the cost of this single installation is probably around €100,000, resulting in a payback time of 196 years, which is still absurd, especially when you consider the research into this project is simply money down the drain.

Given that SolaRoad has been a complete failure, and Solar Roadways is even more ambitious, it’s easy to see that the project is set up to fail. In spite of this, thanks to the money given by the US Government and the backers, the first public Solar Roadways installation (in Jeff Jones Town Square, Sandpoint, Idaho) was recently opened.

None of the 30 panels installed generated a single watt of power, 75% of the panels failed to light up, and after rainfall 4 more failed. This installation cost $60,000 in parts and labour, and every cent of that was wasted. 

The most ridiculous part is that the city of Sandpoint’s budget for 2016-17 includes $500,000 for future Solar Roadways projects!

The project appeals mainly on an emotional level, showing the creators, Scott and Julie Brusaw as a happy couple developing the panels together, and everybody loves renewable energy, but this is just such a terrible, unconsidered way to apply it. 

The reason I would say this is a con, rather than just a misguided dream, is that Scott Brusaw has a master’s degree in electrical engineering. With this level of qualification, there is no excuse to not know that these panels are utterly impractical, which points to nefarious intent.

There’s nothing wrong with solar energy, but this application is like trying to run a wind turbine indoors – roads are such a terrible location for solar panels that it’s hard to believe that anyone at all thinks this is a good idea.