2015 BMW i8 review: The first eco-friendly supercar – ExtremeTech
Meet the 21st century supercar: the BMW i8 plug-in hybrid. It’s insanely fast despite having three cylinders, not eight or twelve. On country roads you cruise in supreme comfort and quiet. The first 20 miles of your trip come from electric power.
The i8 employs electric motors front and back, the gas engine in back, two transmissions, and lithium-ion batteries running through the middle of the cockpit. The body is all-carbon fiber, the fibers coming from BMW’s own hydro-powered factory. The BMW i8 is a Chevrolet Volt on steroids. It is a sports cars with an environmental conscience. The i8 wins our Editors’ Choice award as the best of the new breed of supercars.
Driving the BMW i8: Yowza!
The toughest part about driving the BMW i8 is getting in: You have to climb over a door sill virtually even with the top of the seat cushion, while ducking under the low-slung scissor doors. To paraphrase mama, “Always wear good underwear. You never know when you’re going to the hospital, or getting out of an i8.” Once aboard, the cockpit is surprisingly roomy for a sports car other than the front-to-back tunnel that houses 217 pounds of lithium-ion batteries. It’s also very BMW-like: pushbutton start, a freestanding 8.8-inch LCD display atop the center stack, the eight programmable buttons that tune your favorite stations or call home, the beer tap-looking shifter, the Eco-Normal-Sport rocker switch, and of course iDrive.
Press the button and … nothing much happens once the instrument panel lights up. No V12 engine roaring to life a foot from your ears. That’s because the i8 starts each day as an electric car. But it moves off swiftly. After 20 miles on the 7.1 kWh battery, sooner if you tromp the throttle, you are in gasoline-and-electric mode and aboard a rocket ship. Zero to 60 mph happens in a shade over 4 seconds. Yes, there are old-fashion supercars with 0-60 times under 4.0 seconds, but they aren’t getting 75 MPGe and they’re paying a congestion surcharge to enter megacities. In London, there’s a weekday congestion charge of £11.50 ($18.75); EVs, PHEVs, and ultra-ultra-low emission vehicles are exempt.
Choose economy, performance, some of each
The i8 offers multiple driving modes, set by the shift lever and the Driver Experience Control, which is BMW-speak for a switch next to the shifter with “Comfort” and “EcoPro” rockers. If you do nothing other than pull the shifter straight back into Drive, the i8 is a front-drive EV with a range of 12-20 miles and a top speed of 75 mph. Push the shifter to the left and you toggle sportier driving modes.
Some plug-in hybrids such as the Chevrolet Volt won’t charge the battery while under way because it’s inefficient compared to recharging using electricity. BMW gives you that choice because in sport modes you need the electric motors to act as turbochargers. Even BMW can’t make a three-cylinder gasoline engine alone shove 3,300 pounds to highway speeds in 4-5 seconds. In performance modes, brake regeneration is turned way up and the car slows dramatically the moment you lift off the throttle, the same as when you’re karting, or aboard a riding lawn mower for that matter. If you hammer the throttle — tsk, tsk — and you’re in electric mode, the gas engine kicks in, but there’s a lag that feels like a second before all power sources are present and accounted for.
Next page: Analyzing the BMW i8′s hybrid drive-train
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