Mazda6 Combines ICE with Regen Braking and Super CapacitorsJuly 04, 2013 by Jeff Shepard
Mazda North American Operations (MNAO) has announced updated pricing of its all-new 2014 Mazda6 midsize sedan, now featuring the ground-breaking regenerative engine braking system known as i-ELOOP. When coupled with SKYACTIV TECHNOLOGY, the brand's fuel-efficient and performance-oriented engineering philosophy, the Mazda6 will achieve best-in-class fuel economy amongst competing gasoline-powered vehicles with an EPA-rated 28 city/40 highway/32 combined mpg. When not i-ELOOP-equipped, the 2014 Mazda6 still achieves class-leading highway fuel economy at 38 mpg.
With its name derived from "Intelligent Energy Loop," i-ELOOP is a capacitor-based regenerative engine braking system that converts a vehicle's kinetic energy into electricity as the car decelerates. The electricity captured is then stored for later use to power all the vehicle's electrical components, such as headlights, climate control and audio systems. This reduces the need for the engine to burn extra fuel in order to generate electricity and, therefore, improves fuel economy without sacrificing driving performance. In order to efficiently recapture the kinetic energy and convert it into electricity, i-ELOOP utilizes a 12-V to 25-V variable voltage alternator, a dc-dc converter and a low-resistance, high-capacity super capacitor.
Conventional alternators are constantly charging the battery in an effort to keep up with a vehicle's electrical loads, which means using engine power to operate the alternator, which, in turn, consumes fuel. With the i-ELOOP system in operation, the alternator is free-wheeling, creating almost no parasitic drag on the engine, which reduces the amount of fuel used. Upon vehicle deceleration, the engine and alternator continue to spin as the vehicle slows down, working off of the vehicle's inertia. To take advantage of this free energy, i-ELOOP's special variable-voltage alternator kicks in and generates short bursts of electricity that is stored within the capacitor. The capacitor then meters power out into a smooth, continuous flow to satisfy energy loads.
"Mazda is again changing the game of automotive engineering, this time making fuel efficiency not seem as a compromise but a true complementary feature as part of the complete vehicle package," said Jim O'Sullivan, president and CEO, MNAO. "With the addition of i-ELOOP, the 2014 Mazda6 will achieve the best mileage for a non-hybrid midsize sedan. But fuel economy isn't the sole focus of our engineering and design teams, as being a leader in dynamics, design and safety create a win-win for the company and consumers."
While the increased engine braking caused by the hard-charging alternator is too small for drivers to feel, the smooth power delivery coming from the capacitor means the electrical systems do not operate differently with i-ELOOP. Exact fuel savings will vary based on electrical load and individual driving habits.