Saab Sonnet III (c1970)
the final evolution of Saab’s sports car was powered by a Ford V4 engine but it was also used as a test bed for an experimental steam engine known as project ULF. the 250hp 9 cylinder steam engine required minimal fossil fuel and produced tiny carbon emissions. Saab believed that they had overcome most of the difficulties associated with this type of engine but the project was shelved.
the red test car survived and was auctioned in Stockholm in July 2019.