The Lexus' whirligig is familiar from the Toyota Camry and Avalon hybrids: a lean-burning Atkinson-cycle, 2.5-liter in-line four-cylinder (156 hp) coupled with two electric motors, one a 141-hp traction motor, the other a starter-generator.

WSJ: 2013 Lexus ES 300h Review: A Smooth, Elegant Guilt-Eraser | Rumble Seat by Dan Neil

In E-mode, only the 114-hp rear electric motor propels the vehicle and the TDI engine is shut off and decoupled from the drivetrain.

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The electric drive produces 95 hp, more than double the power of the previous model's electric motor (47 hp).

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Simply put, all of the power that goes to the wheels of the Volt goes through its 111 kW (149 hp equivalent) electric motor.

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The c's program managers were thus obliged to dial back to the previous generation's 1.5-liter engine (the Gen III Prius uses a 1.8-liter), a smaller traction motor (60 hp vs. 80 hp) and a lighter, cheaper nickel-metal hydride battery (19.3 kilowatts vs. 27 kW).

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The car uses a 1.8-liter, 98-horsepower four-cylinder gasoline engine with an 80 hp (60 kW) electric motor charged on a Ni-MH battery.

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It consists of a GM-designed, coaxial drive unit and electric motor that together deliver 130 hp (110 kW) and 400 lb.

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Because peak power arrives at different rpm for the gas engine and the electric traction motor, peak system horsepower nets out to be an even 200 hp at 5, 600 rpm, which is the rated redline.

WSJ: 2013 Lexus ES 300h Review: A Smooth, Elegant Guilt-Eraser | Rumble Seat by Dan Neil