Questions have been raised regarding Swedish Koenigsegg, set to buy Saab from GM, and its new environment-friendly car.

Christian Koenigsegg, founder of the Swedish sport carmaker with the same name, is developing a new environment-friendly supercar. However, Swiss experts are now questioning if the technology exists at all, according to media sources.

The inquiring comes in a squeamish time for Koenigsegg as the carmaker is the leading part in a consortium set to acquire Swedish luxury car Saab from General Motors in a deal likely to be worth 5 - 10 billion kronor (€467 – 952 million).

The clean vehicle is a concept car called NLV Quant. It was launched during the Geneva car show this spring with the aim to be sold to consumers within two years.

The car, that’s been developed in collaboration with Christian Koenigsegg’s Swiss partner Nunzio La Vecchia, is to be run with solar energy where “groundbreaking thin-flm solar-cell coating is being implemented in one of Koenigsegg’s signature avant-garde designs” the company said as it was released.

However, several experts are questioning the solar energy technology, according to business daily Dagens Industri that referes to Swiss newspaper WOZ.

For example, the production was to be made in premises rented by German Siemens. But the production hall is empty – and the Swiss company refuses to answer questions regarding how many persons that are involved in the project.

At the same time Nunzio La Vecchia is being questioned regarding his PhD and private wealth. He says that he finances his businesses with private money, but there’s still fuzziness from where the wealth derives.

The environment-friendly supercar is not the only piece of the company that's held in the dark. There are also uncertainties about how much funds Koenigsegg Group is ready to inject in Saab and if loan guarantees would be needed.

"We still don't have any information about the amount of money they are willing to invest. And that is a key point. The other is the ability to lead the company," Sweden's Industry Minister Maud Olofsson said in a Reuters interview on Thursday.