Fisker is scheduled to announce an aluminum space frame for its Karma vehicle at the Geneva Motor Show. The structure will be the basis of the Fisker Karma plug-in hybrid once Finnish firm Valmet Automotive begins assembly of the platform.

The production for the Karma is expected to begin in May. It will feature GM’s 260 horesepower (194 kW / 264 PS) Ecotech 2.0-liter turbocharged engine, and a rear-mounted electric motor producing 403 horsepower (301 kW / 409 PS).  The Fisker Karma is expected to have an all-electric range of about 50 miles (80.5 km) courtesy of its lithium-ion battery pack.

“Our top priorities when we designed the Karma’s aluminum space frame were that it have extremely high torsional rigidity and could be easily modified to accept Karma model variants,” said the automaker’s chief, Henrik Fisker. “We benchmarked some of the world’s best cars to create an all-new space frame that will deliver an exhilarating experience behind the wheel.”

The Fisker Karma will hit US showrooms by September with a price tag of $87,900.