How do we generate the energy for electric vehicles?

Dr David Williams

How do we generate the energy for electric vehicles?

The answer could be under our wheels, says
Dr David Williams

In July this year the government announced that it would be banning the sale of petrol- and diesel-engined vehicles by 2040. In reality, this is likely to happen sooner, as manufacturers bring more electric vehicles to market. At present, we have yet to reach the tipping point where businesses and drivers decide to switch, with ultra low-emission vehicles (ULEVs) making up only a tiny fraction of newly registered vehicles and an even smaller percentage of the overall vehicle fleet.

The company car market has an important role to play in this switch because it accounts for over half the new vehicles registered in the UK, meaning that these technologies need to be embraced now by the company car sector so they can filter down into the secondhand car market over the next two decades.

This change to ultra low-emission vehicles will have other implications as the country shifts to one primary energy source: electricity. This will place even more pressure on the already stretched National Grid. So how can it provide enough energy for the country’s motor fleet in the future? One answer may be under our very wheels: harnessing energy from the highway network.

The highway is exposed to different forces every day from solar radiation and wind to the movement of both water and vehicles across the network. If it was possible to harness a tiny fraction of this energy across the whole network we could produce more than enough electricity to enable the switch to ULEVs to occur without putting undue stress on the existing grid.

Technologies to produce energy from the highway exist and have been trialled across the world, but all have stalled at the prototype phase due to both their cost and the low energy returns. A hybrid system harnessing multiple energy sources would alleviate this issue, providing a stable supply of energy. This energy could then be stored close to the highway, further reducing the inefficiencies in the system.

The government has set itself a realistic target to switch the UK’s motor fleet to ULEVs, so now is the time to invest in truly low carbon solutions to minimise the impact of this switch.

Dr David Williams is a Research Associate at the University of the West of England. In July, Dr Williams won the Wolfson Economics Prize Lightbulb Award for Innovation.