It will do so using devices called thermionic energy converters (TECs), which consist of a hot electrode that thermionically emits electrons over a potential energy barrier to a cooler electrode, producing a useful electric power output.
Dr Fox is developing special electrodes for the converters using nanoparticles of industrial diamond powder, which is low cost and readily available.
TECs are commonly used in space vehicles, but Fox’s new electrodes are designed to lower operating temperatures while maintaining a potential energy-conversion efficiency of more than 40 per cent.
The project, known as the Lithiated Nanoparticle Diamond Energy Converter, should enable a TEC to operate satisfactorily on solar power, leading to a renewable-powered generation device that has no moving parts or fluids, is free of maintenance and is able to deliver reliable electricity production over a long period.
It aims to achieve operation below ‘red heat’ level, possibly as low as 320°C. Conventional TECs with metal electrodes require temperatures well above 1,500°C to produce sufficient electrical current.
Trials featuring a system using the converters, some of which will take place in the south west, will use parabolic dishes to concentrate the Sun’s rays. If successful, the technology could provide an alternative to photovoltaics.
Speaking about the project, Dr Fox said: ‘It is a very ambitious project, but thanks to E.ON we now have the people and equipment in Bristol to make advances that will help realise a solar thermal technology that can work outside the sunbelt regions of the world.’