A spy shot of the 2021 Porsche Panamera Sport Turismo

Porsche's second-generation Panamera is gearing up for a minor facelift as it approaches the middle of its lifecycle.

The latest prototype is a Panamera Sport Turismo station wagon. Previous testers showed a regular sedan in a liftback body.

The current Panamera was introduced in 2016 as a 2017 model, so the updated version will likely appear in late 2020 as a 2021 model.

The prototype received new front and rear fascias. The taillights have also undergone changes, with the center strip connecting the individual light clusters receiving a new design that will eventually be similar to the design used on the latest versions of the Porsche Cayenne and Macan SUVs.

In addition, as is common with mid-cycle updates to Porsche vehicles, various models in the Panamera lineup should receive more powerful engines.

Currently, the Panamera lineup starts with a base model with a 3.0-liter turbo V6 engine with 330 hp, followed by a twin-turbo 4.0-liter V8 with up to 680 hp and the Panamera Turbo S E-Hybrid plug-in hybrid.

One possible option is the addition of a 48-volt hybrid system, possibly utilizing an electric compressor.

Many automakers are beginning to introduce mild hybrid systems. This is essentially an advanced starter motor that assists the engine at high loads and recovers energy during braking or coasting. In some cases, it can also power an electric compressor and help boost the boost pressure of a power-driven engine before increasing rpm and switching to a conventional supercharger or turbocharger. Some models of Porsche's sister brand Audi already utilize this technology.

Porsche is also known to be testing a new version of the Panamera with a more radical aerodynamic dodger. There has been no official confirmation of production, but there are rumors that it could arrive this year as a limited edition to coincide with the brand's 10th anniversary.