CIGS cells set Swedish fuel efficiency record in Shell Eco Marathon
KTH uses Midsummer's solar technology to achieve 181.5 km/kWh
The Swedish Royal Institute of Technology (KTH) has set a new Swedish fuel efficiency record achieving 181.5 km/kWh in the Shell Eco Marathon competition for a solar powered car called 'Elba'.
In the race, European universities to compete with innovative solutions for how far a vehicle can travel with the energy equivalent to a litre of fuel. KTH's car was fitted with thin solar cells made by Midsummer, a supplier of production lines for cost effective manufacturing of flexible thin film solar cells, CIGS (copper, indium, gallium and selenide). It came fifth.
In the contest, which was held in Rotterdam in the Netherlands, the new improved 'Elba' was able to set a new Swedish record of 181.5 km/kWh, which can be compared to a car that drives a distance of 158 kilometres for a total cost of around 1 Swedish Krona (0.11 EUR or USD 0.15).
"The solar cells needed to be integrated into the car's design," said Alex Witt, production manager at Midsummer. "The only possible solar solution that would integrate in Elba's aerodynamic shape was Midsummer's flexible thin film solar cells on stainless steel, which could easily follow the curved body of the vehicle without cracking. This solution would have been impossible with silicon solar cells as they crack easily."
"In this year's competition KTH used last year's car 'Elba', which was rebuilt. The custom-made flexible solar cell modules were placed strategically on the vehicle to optimise the exposure of the sun and thereafter connected in series to generate as high voltage as possible into the system," Witt added.
Midsummer has developed a rapid process for the production of CIGS solar cells using sputtering of all layers of the solar cell.