2019 Audi A7 -There is also a fuel-saving start-stop system that uses the front-facing camera to monitor the movement of the vehicle ahead. When that vehicle starts moving, the A7’s engine is automatically re-started. Regenerative braking of 12 Kw is also part of the A7’s mild hybrid system. Combined, these fuel-saving measures account directly for a 0.7 liters per 100 kilometers reduction in fuel consumption.