Constructing roads which can charge cars while they are driving could help reduce the size of batteries needed on electric vehicles by up to 70% a new Swedish study has found.
Sweden’s Chalmers University of Technology has undertaken research which for the first time combined the possible use of an electric road system with real-life driving patterns of Swedish drivers.
Trials of electric roads - where vehicles are powered by overhead wires similar to those used by railways - have taken place in a number of European countries as solutions are sought to move the transport sector beyond the internal combustion engine.
Other positive effects are that peaks in electricity consumption would be reduced if car drivers did not entirely rely on home charging but also supplemented it with electric road charging.
The Chalmers University of Technology study, which was commissioned after the Swedish government proposed a ban on new petrol and diesel cars from 2030, used data from over 400 passenger cars to study real driving patterns on different parts of Swedish national and European road network.
Researchers used the data to calculate, among other things, battery size needed to complete all journeys given possible charging options (stationary versus ERS), charging patterns and total costs including infrastructure and batteries.
The results found that a combination of electric roads on 25% of the busiest national and European roads and home charging would be optimal. The batteries, which account for a large part of the cost for an electric car, can become significantly smaller, at best only one-third of the current size.
"We see that it is possible to reduce the required range of batteries by more than two thirds if you combine charging in this way. This would reduce the need for raw materials for batteries, and an electric car could also become cheaper for the consumer," said Sten Karlsson, co-author of the study together with research colleagues Wasim Shoman and Sonia Yeh.
Fellow researcher Wasim Shoman said: “There are big differences between groups, depending on driving patterns and proximity to electric roads. Even in the optimal case, some would manage with only electric road charging, while others would not be able to use the opportunity at all.
“For example, we see that those who live in the countryside would need almost 20% greater range on their batteries compared to those who live in a city centre.”