KOREAN car makers Hyundai and Kia are to use power from the sun to boost the performance of their models.

After next year, solar panels will be fitted to the roofs of certain vehicles from the two brands to provide extra energy.

The sister companies are working on three sets of technology to use the panels on conventionally engined vehicles as well as on hybrids and pure electric cars.

The first-generation system, which will be applied to hybrid models, is created out of a structure of silicon solar panels that are integrated into a standard car roof.

This system is capable of charging 30 to 60 per cent of the battery over the course of a normal day, depending on weather conditions and other environmental factors.

The second-generation semi-transparent solar roof will be applied to regular combustion vehicles, representing a world-first application for the technology.

The semi-transparent technologies can be integrated with a panoramic sunroof, letting light through into the cabin, whilst charging the vehicle's battery at the same time.

Applying solar charging systems to ICE vehicles will help them comply with ever more stringent global environmental laws regulating CO emissions.

The third-generation system, is currently undergoing testing and is designed to be applied to the bonnet and roof of eco-friendly battery electric vehicle models in order to maximise energy output.

"In the future, we expect to see many different types of electricity-generating technologies integrated into our vehicles," said Jeong-Gil Park, executive vice president of the engineering and design division of Hyundai Motor Group.

"The solar roof is the first of these technologies, and will mean that automobiles no longer passively consume energy, but will begin to produce it actively. It is an exciting development for us, designing a technology for vehicle owners to help them shift from being energy users to being energy producers."

The solar charging system is composed of a solar panel, a controller and a battery. As the panel absorbs photons of light from the sun, it creates electron-hole pairs in silicon cells, enabling current to flow and generating electricity.

When a 100W solar panel is equipped, it can produce up to 100 Wh of energy in ideal conditions. The power is converted and stored in the battery, or utilized to decrease load on the vehicle's alternating current generator, increasing vehicle range.