Graphene to drive next-generation fuel-efficient cars

Scientists from the University of Manchester are working on a new application for the wonder-material, graphene, to help develop more efficient vehicles by converting waste heat into electricity.

The collaborative project between the university and thermal management firm, European Thermodynamics Ltd, aims to use super-conductive graphene to harvest the heat produced by motor engines and use it to recharge the vehicle’s battery or power other functions such as the air conditioning system. 

Efficiency opportunity

According to the researchers, the average car currently loses around 70 per cent of the energy generated through fuel consumption as waste heat. 

Harnessing this wasted energy requires the application of a thermoelectric material, which can convert heat to electricity or vice versa. 

Highly-efficient thermoelectric materials conduct electricity and dissipate heat well but are often toxic and operate at very high temperatures of up to 700 degrees Celsius, making them unsuitable for use in vehicles.

‘Huge potential’

However, by using graphene – a highly conductive ‘wonder’ material consisting of a single layer of carbon atoms – researchers have developed a composite thermoelectric material that safely performs at room temperature, opening up the automotive industry to whole host of low cost applications to improve fuel efficiency and reduce emissions. 

Professor Robert Freer, part of the team working on the project, said: “Our findings show that introducing a small amount of graphene to the base material can reduce the thermal operating window to room temperature, which offers a huge range of potential for applications.

"The new material will convert 3-5 per cent of the heat into electricity. That is not much but, given that the average vehicle loses roughly 70 per cent of the energy supplied to it by its fuel to waste heat and friction, recovering even a small percentage of this with thermoelectric technology would be worthwhile.”

Furthermore, using graphene as a composite material in chassis or bodywork could also aid fuel economy and safety by significantly reducing vehicle weight. 

Green breakthroughs

The development is the latest in a growing line of graphene-related breakthroughs for energy efficient technology. In March 2015, the £61 million National Graphene Institute (NGI) announced that it was planning to launch a super-efficient long-lasting LED lightbulb as its first spin-off product.

The NGI was established to help Manchester maintain its leading position in developing graphene following its discovery at the University of Manchester in 2004. 

The institute pulls together over 200 researchers and 40 commercial partners working to develop products for the market.

Posted under Environmental Technologies and Renewable Energy, Automotive and Environmental Technologies on 4 August 2015