Always, it seems, on the automobile design avant-garde, Lamborghini surprised the industry and its watchers this week when it unveiled a new Sián—one with a rather unusual powertrain. The hybrid supercar is partially powered by supercapacitor technology. And, as opposed to the coupe version, this one’s roofless. Not convertible, simply roofless.

Lamborghini’s new car gives supercapacitor-based energy a little bit of much-needed exposure. The cool blue car (actually, it’s coated in a shade of metallic aquamarine) features a supercapacitor instead of the expected lithium-ion battery.

Now, this is decidedly not a supercapacitor-powered car. What’s at work most enthusiastically is, in fact, a naturally-aspirated V12 ICE. The supercapacitor is only present in a supporting context—negating gear-change lag and parking the car. For a fully supercapacitor-powered car, we’ll have to wait a bit. We’ll see what the end of the decade looks like.

The Sián Roadster is limited to 19 units and is already sold out. The price is said to be north of $3 million. In related news, Lamborghini recently teamed up with Tecnomar for a yacht inspired by the Sián.