Usually when AC Schnitzer lays their modifying Midas touch on a Bimmer, they throw some massive horsepower and headturning body kits on a car and call it a day. But with their latest release, the 99D Concept Coupe, the German tuners are aiming straight for the Green Zone with a performance car that emphasizes efficiency. The 99D Concept Coupe, based on the BMW Z4, is named thus because it only releases 99 g of CO2 emissions — that’s less than any standard BMW vehicle currently available. And the diesel engine-powered car manages to do so while still generating 190 HP (140 kW), and accelerates from 0 – 62 mph in 6.9 seconds with a top speed of 146 mph. All while using only 3.8 litres of diesel per 62 miles (100 km). These numbers are accomplished via a series of AC Schnitzer “secrets” like: shedding 507 lbs (230 kg) of weight by incorporating lightweight materials such as carbon, magnesium and titanium, and swapping the lead battery for a lithium ion one; dropping another 77 lbs (35 kg) of unsprung mass via forged rims and braking system; the use of specialized Eco-tyres from Continental; adaptation of the EfficientDynamics technology package (automatic start-stop, brake energy recuperation, low-friction lubricants, active aerodynamics, etc); improved aerodynamics and reduced friction. Of course the AC Schnitzer 99d is only a concept car built to showcase their technology packages and thus not for sale, but in the form shown here the vehicle would cost $215,000 (€ 149,000).