SOLAR panels could be added to electric cars to prevent them running out of charge just to keep their Scottish drivers warm.
Up to 40 per cent of battery power is used to heat vehicles on winter days, researchers at Edinburgh Napier University have found.
This is because electric cars don’t produce “waste heat” like petrol or diesel models which can be channelled into warming their interiors.
The university already uses solar panels on the side of a building to charge the equivalent of 12 electric cars a year.
Staff believe that installing panels on the roof and bonnet of vehicles would significantly reduce the drain on their batteries on cold days.
These could also be used in the summer to power fans to keep the cars cool.
The development would help ease the “range anxiety” – fear of running out of power – which has put drivers off buying electric cars.
The range of many current models is around 100 miles, with some 450 charging points across Scotland, including 100 rapid chargers which take 20-30 minutes.
Research student Aisling Doyle said that heaters in some electric cars used more power than for the average car trip.
Doyle said: “My experience of driving the Nissan LEAF was the instant I turned on the heater or air-conditioning, the range of the vehicle on the display dropped.
“I have experienced a drop of over 13km (eight miles) in one instance, when the average car trip length is 12.1km (7.5m). By turning on my climate control system that day, I lost a whole trip.”
The student, who is working with professors Tariq Muneer and Ian Smith at the university’s transport research institute, said: “Solar panels installed on the roof and bonnet of a vehicle could potentially improve the thermal performance of electric vehicles and contribute to reducing ‘range anxiety’ for future drivers.
“The proposed new system will heat the vehicle before the driver enters the cabin during cold temperatures using heaters.
“Additionally, during warmer periods, the solar panels will supply energy to extractor fans to reduce temperatures.
“This will reduce the electrical loading on the vehicle’s battery to allow more energy for the propulsion of the vehicle.”
The Institute of Advanced Motorists welcomed the move but said electric cars remained less attractive than traditional vehicles.
Neil Greig, its Scotland-based policy and research director, said: “This looks like a good project and certainly addresses a key worry about electric cars – can they cope with a Scottish winter?
“The network of charging points is growing, which helps with range anxiety, but we are still some way off the electric car offering the flexibility of a traditional vehicle.”
There are more than 1,700 electric vehicles on Scotland’s roads, with some 700 sold so far this year, according to Scottish Government and industry figures.
Car-sharing clubs north of the Border have more electric vehicles than the rest of the UK combined.
Dundee has the UK’s largest electric taxi fleet, and Scottish councils are among the heaviest users.
However, electric vehicles still account for only one in 1,000 vehicles in Scotland and one in 100 sales.
Despite this, Scottish ministers want to rid the country of petrol and diesel vehicles within 35 years to cut damaging emissions.
A spokesman for the Scottish Government’s Transport Scotland agency said: “An increase in numbers of electric vehicles will also complement the development of the Scottish renewables sector, ultimately making electric vehicles charged in Scotland some of the cleanest in the world.
“Cleaning up the road transport sector will help meet Scotland’s ambitious climate change targets and reduce the serious harm to our health and wellbeing caused by emissions from fossil-fuelled vehicles.”