On Friday, BMW revealed the next-generation X5 plug-in hybrid, with significantly more electric range and a 6-cylinder engine replacing the 4-cylinder in the current X5 plug-in hybrid.

Based on the new third-generation X5, BMW says theX5 xDrive45e iPerformance will have up to 50 miles of electric range from an expanded battery pack that sits mostly under the floor of the car. That's a significant improvement from the 14-mile electric range rating in the current 2018 BMW X5 xDrive40e. BMW's estimates were based on European specs.

Like the current model, BMW implies that the new X5 xDrive45e iPerformance will seat five, without the optional third-row seat in non-plug-in X5s. The cargo space is about 5.3 cubic feet smaller than gas-powered X5s.

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Electric power goes up marginally from 111 to 112 horsepower.

On its own, the new inline-6 produces 286 horsepower, up from 240 hp. Overall power, goes up to 394 horsepower and 442 pound-feet from 308 and 332.

The new X5 uses the same 8-speed automatic transmission with its integrated electric motor as the current X5 xDrive40e, and comes standard with the same mechanical all-wheel drive system as other X5s.

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The bigger battery should let more parents run more around-town errands without using gas, and that dramatically improves the plug-in X5's overall MPGe estimate from 56 MPGe for 2018 to an estimated 109 to 112 MPGe based on BMW's European fuel economy and emissions claims.

Top speed in electric mode has been raised from 74 mph to 87 mph.

The new X5 isn't expected to go on sale until sometime in 2020 as a 2021 model, and BMW hasn't yet said how much it will cost.