Could a road made entirely of glass support the weight of a lorry? Yes, if the couple behind the Solar Roadways project are to be believed. Solar Roadways are a modular paving system of solar panels made out of glass. The idea, conceived by Scott Brusaw, an electrical engineer with over 20 years of experience, is simple: replace traditional asphalt and concrete road surfaces with solar panels that could be driven on. This idea is supported by one of the United States Senators for Idaho, Republican Mike Crapo, describing how the project would ‘create jobs and lessen our dependence on fossil fuel while utilising available resources’.[i]

A contract from the Federal Highway Administration (FHA) was granted to Brusaw in 2009 to build the first ever Solar Road Panel prototype and car park, which has been tested under all weather and sunlight conditions. The contract is due to end in July 2014, at which point more information should be available about the success of the project. Containing a heating element, the specially designed solar panels could prevent the build-up of snow or ice in more northerly climes, which would potentially do away with gritters.[ii]

A road of solar panels would allow electric vehicles to recharge anywhere, giving them the same range as petrol-powered vehicles. Brusaw also claims that solar roads have national security implications. ‘Centralised power plants create security risks’ Brusaw says, with hackers and terrorists being able to take them out and areas being left powerless by attacks. Conversely, a decentralised system would be far safer – if a terrorist detonated a bomb in the middle of a Solar Road and the road is blown in half, because both sides still produce electricity, no one loses power. The same logic is applied to roads affected by natural disasters such as earthquakes. Whilst the effects of quakes on the solar panels are unknown, with asphalt roads, large cracks appear after a quake and the whole road has to be fixed, whereas any panel damaged could be individually replaced.

The panels will not only replace roads, but could also be used on pavements, driveways, tarmac and car parks, and each panel can be replaced at a time, meaning it would be quicker and easier than it usually takes to fix potholes. Every panel has a series of LED lights, which means particular messages – warning signs, the stripes on the road at pedestrian crossings and so on – will be produced electronically and not painted on. The panels are also pressure sensitive, able to detect animals or obstacles on the road, making them capable of informing drivers to slow down.

The project, perhaps unsurprisingly, has its naysayers. One concern seems to be involving the glass used on the solar panels. Can the panels withstand heavy lorries driving over them frequently every day? The Mohs hardness scale is used to define hardness in material science. The hardest material is diamond. Asphalt ranks about 1-2 on the scale, whilst glass is 4.5-6.5, with diamond at number 10.[iii] The glass in the panels is tempered and, according to Brusaw, has been ‘designed and tested to meet all impact, load and traction requirements’.[iv]

Anthony Watts, a former television meteorologist and creator of the website Watts Up With That? which describes itself as ‘the world’s most viewed site on global warming and climate change’, is also not convinced, claiming that Brusaw has duped many ‘gullible people’ into giving money to the project. These supporters, Watts argues, are people ‘who don’t have the skill set or decide to ignore basic physics, economics, and common sense in favour of future pipe dreams of green energy’.[v]

Yet the Advisory Board of the Solar Roadway project includes Professor Carlo G. Pantano, Distinguished Professor of Materials Science and Engineering and Director of the Pennsylvania State University Materials Research Institute; a couple of people with engineering doctorates, a commercialization expert and a product designer, inventor and entrepreneur.[vi] The fact two rounds of funding have been provided from the FHA also indicates there is some support for this in parts of government.

Many of the ideas of the project are just that; the recurring phrase on the project’s website is ‘We don’t know’. Thus far, the only place which has these panels is a car park in Sagle, Idaho (where Brusaw lives), which contains 108 prototype panels. Brusaw and his wife, Julie, have been making requests for funding and, as this has now been achieved, they hope to push on quickly with more projects. The orders so far include a car part for a visitor centre, the tarmac at the local airport and a train station platform. A break-down of costs is not yet available, and won’t be until the FHA contract expires and the project can then be assessed.

Its costs, it seems is the main sticking point. The expense of the project has been questioned. In 2010, when the project was first gaining attention in America, science writer Aaron Saenz wrote that making roads out of solar panels would be like making them out of gold.[vii] And, as Ian Bowles, energy investor at Windsail Capital told the Boston Globe recently, ‘This seems like one of the longest putts you could come up with in solar’.[viii] Until costs are revealed, it is unlikely any large scale investments will occur. It has been estimated that poor road surfaces cost US drivers, on average, $324 per year in vehicle repairs, which totals $67 billion.[ix] Just over $40 billion was provided by the federal government in the financial year of 2014, most of which is used to upgrade and maintain America’s core highways, including the Interstate Highway System. Each year, the US spends more repairing and maintaining existing roads than it does building new ones.[x]

Whilst the overall cost of the roadways is unknown, the roads, the Brusaw’s envisage, will be cost-effective in the long run. Money for these roads could be gathered from savings made by not using petrol engines, not having to grit the roads, and not having to fill potholes. And it would keep people in employment, producing solar cells. The panels have been produced in an environmentally-friendly way, containing only small levels of copper and no gold or silver, and any kind of solar cells can be used in the system. That way, the project can occur in an optimally environmentally friendly way.

The plans are still a long way off creating widespread solar roads, so don’t expect relief from pot holes or gritters any time soon, if at all. The project might never come to fruition on a grand scale, dwarfed by costs or technological failings. And in reality, it might be a project that promises everything and delivers nothing. However, until more cost estimates come back, and the results of the prototypes are released, nothing is clear. As Jonathan Levine, professor of urban planning at the University of Michigan told Popular Mechanics in June this year, providing the science and technological stuff works, then this sort of project is ‘readily deployable at a small scale’.[xi] Trying to convince a state to replace all their highways with solar panels might result in you being laughed at, if this is applied on a micro scale – in a car park, say – then it might work. Whilst there are still questions to be answered, the roads of the future could well be paved not with gold but with solar panels.

 

Sources:

[i] Senator Mike Crapo appears in a YouTube video, on the Solar Roadways website, and describes some of the benefits of it: http://www.solarroadways.com/intro.shtml.

[ii] See http://www.solarroadways.com/intro.shtml for more information.

[iii] For hardness and the mohs scale, see: http://www.tedpella.com/company_html/hardness.htm; See also http://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness.

[iv] Jackie Vega, ‘Solar Roadways rocket past $1 M goal at $2.1 M’, 18 June 2014: http://kxan.com/2014/06/18/solar-roadways-rockets-past-1m-goal-at-2-099m/.

[v] Anthony Watts, ‘Solar Roadways – Biggest Indiegogo Scam Ever?’, 4 June 2014: http://wattsupwiththat.com/2014/06/04/solar-roadways-biggest-indiegogo-scam-ever/.

[vi] See the Advisory Board of Solar Roadways: http://solarroadways.com/board.shtml.

[vii] Adrianne Jeffries, ‘Crazy plan to cover the nation’s roads with solar panels raises $1 million’, 26 May 2014: http://www.theverge.com/2014/5/26/5751880/plan-to-cover-roads-with-solar-panels-raises-1-million; Scott Lee, ‘US Solar Roadways Plan Hitting Snags’, 1 June 2014: http://news.filehippo.com/2014/06/us-solar-roadways-plan-hitting-snags/.

[viii] Scott Kirsner, ‘Bright future for solar roads?’, 13 Junw 2014: http://www.bostonglobe.com/business/2014/06/13/investors-see-bright-future-for-solar-firm-are-they-blinded-light/0O6fTWI8HA06OmxUndiNqJ/story.html.

[ix] Road Works – the Value of Smooth: http://digitalmagazinetechnology.com/a/?KEY=betterroads-11-08august&fp=38&title=August%25202011#page=7&zoom=1.

[x] American Road & Transportation Builders Association, ‘Transportation FAQs’: http://www.artba.org/about/transportation-faqs/.

[xi] Micaehl Belfiore, ‘We Could Build a Solar-Powered Roadway. But Will We?’, 11 June,, 2014: http://www.popularmechanics.com/technology/engineering/infrastructure/we-could-build-a-solar-powered-roadway-but-will-we-16879565.