Bentley on Wednesday filled in some of the details on how it plans to become strictly an EV brand by the end of the decade.

The automaker in 2020 said it planned to launch its first EV in 2025 and would sell only EVs by the time 2030 rolled around, the date by which Bentley's home market of the U.K. is looking to ban the sale of cars powered purely by an internal-combustion engine.

Now Bentley has confirmed it will launch five EVs in five years starting with that first EV in late 2025. The four subsequent EVs will then be launched on an annual basis, and each will be completely new. Bentley calls the move to electric propulsion the biggest transformation in the company's history.

It's part of an investment worth 2.5 billion British pounds (approximately $3.37 billion) that will also see Bentley's plant in Crewe, U.K., upgraded to handle production of EVs, while also incorporating digital and flexible manufacturing technologies.

Artist's impression of upgraded Bentley plant in Crewe, U.K.

Artist's impression of upgraded Bentley plant in Crewe, U.K.

The upgrades will also help the plant become even more environmentally friendly. According to Bentley, the plant is already carbon-neutral thanks in part to extensive solar arrays lining the roof. These solar arrays will be expanded, while other environmental aspects like water and waste management will be addressed. Bentley will even look at using sustainable biofuel in its fleet cars, including the heritage fleet.

Bentley also plans to work with its suppliers and dealer network in an attempt to reduce emissions. The automaker has set itself a goal to be carbon-neutral across its entire operations by 2030.

As for what the EV model will be, Bentley said the current cars will run out their life cycles then switch to EV versions. Therefore, the new lineup will include EV versions of the Bentayga SUV, Flying Spur sedan, Continental GT coupe, and Continental GT convertible, plus, perhaps, one other vehicle. The vehicles will be developed in the U.K. and built at the Crewe plant. The first EV is expected to be linked to Audi's Artemis project which is a research project for the next A8. Bentley is part of the Audi brand group, and the new vehicle is expected to be sleek, aerodynamically shaped crossover blending elements of a sedan and SUV. Bentley CEO Adrian Hallmark previously described it as being something like the Jaguar I-Pace but bigger and bolder.

Before the first EV arrives, Bentley will continue to add plug-in hybrid technology to its current lineup. The Bentayga and Flying Spur are already available with a plug, and by 2026 every Bentley sold will either be a plug-in hybrid or an EV.

—Senior Editor Kirk Bell contributed to this report.