Could Solar Roads Become a Reality?

If you travel on roads in the UK, you'll have noticed that many speed signs and traffic information boards now run on solar power.

Using solar power is a great way to harness the free energy of the sun and reduce the use of traditional electricity used in the past.

But how much further is this trend likely to go? Well, one eco-inventor in the USA is currently developing a prototype for a solar road – a new type of road surface that will absorb the sun’s rays and generate power.

Research

At the moment, the reality is a long way off but the US government believes the theory is sound and has given inventor, Scott Brusaw a business grant of $100,000 to develop a short stretch of the power-generating roadway.

The idea is to create a road from glass, which is well known for its strength and Idaho-based Brusaw believes that eventually, solar roads could mean the end of traditional power stations.

Currently, he is working with researchers at Penn State University to try to develop a suitable surface. There are many problems – not least that the finished product would need to be textured so that tyres can grip but water will also need to run off.

The surface will need the strength to last for many years and will also need to be self cleaning so that the solar panels don’t quickly become obscured by dirt and dust.

The material is likely to be extremely expensive but Brusaw points out that by generating energy, it will more than earn its keep - unlike traditional asphalt road surfaces.

Obstacles

Clear glass would be great for the photovoltaics needed to produce solar energy but since cars would slide, researchers need to find a way of grooving the glass without losing its transparency.

One of the next hurdles will be the batteries or massive capacitors needed to store the charge produced by the roads.

And of course there is the complication that at busy times, stationery vehicles in a traffic jam would obscure much of the solar road surface and cast shadows over still more.

But Brusaw believes it is achievable and that one day, solar roadways could replace fossil fuel power stations.

An additional feature of the solar road is likely to be the installation of charging stations for all the electric cars we’re likely to see in the future, allowing them to be re-fuelled by the stored solar energy.

The surface would also include heating elements which hopefully could solve the current winter problems of icy roads and snow-closed motorways.

Testing

If and when the solar road project finally moves off the drawing board, the new road surface is likely to be tested first in car parks where vehicles don’t travel at speed.

Finally, if Brusaw’s theory sounds like pie in the sky, it’s worth pointing out that a 500-foot glass footbridge already exists in Washington DC and glass experts confirm that it is possible to massively increase the strength of glass using a method of compression.

If the project is a success, there could be untold benefits for the environment in the long term.

Of course it’s unlikely that engineers would begin to dig up long stretches of road to fit the solar panels but they could be introduced when road surfaces are nearing the end of their life.

Costs

The cost is estimated at around 65p per square foot of road (at 2010 prices) but the expensive installation costs would be repaid by the huge amounts of electricity which the new roads would generate.

It is thought that a single mile of dual carriageway could provide enough electricity to serve 500 average homes. The solar roads would also have wind turbines which could top-up the power generation at night.