Mazda’s most recently redesigned models all feature the SkyActiv badge—corresponding to a suite of engines, transmissions, body structures, and other core components engineered around the idea of maintaining a responsive, sporty driving feel while making major improvements in fuel efficiency.
Beyond that, the SkyActiv efforts have produced a few more especially innovative things that won’t initially be offered on every Mazda. One of them is termed i-ELOOP
—for intelligent energy loop—and it’s right on course to that aim of improving gas mileage in totally unobtrusive ways.
The system, which is available on the Mazda 3 and Mazda 6, uses capacitors, rather than additional batteries, to recover and store energy when decelerating or braking; then it takes that stored energy and releases it to power vehicle accessories.Smarter than smart alternators?
In effect, it’s a step ahead of other ‘smart alternator’ systems—such as the one that BMW has offered for several years—but it’s not quite a mild hybrid system. There’s no engine assist provided by the system, although it allows the load of the alternator to effectively be eliminated in some situations when you’re accelerating.
Mazda engineers argue that the benefits are more pronounced, though. Capacitors can store energy faster, and release it faster, so the system fits driving stop-and-go (and uneven commuter driving) realities. Engineers can really maximize the capability of the alternator and generate as much energy as possible (although the overall capacity of the system is much smaller than that of a typical hybrid’s battery pack and hasn’t yet been detailed).
From the driver’s seat, you can bring up an efficiency display through the new Mazda Connect display; there you get two screens: a histogram graphing out average efficiency, and a schematic showing (like other hybrids) energy flow and the current charge level of the capacitor system.A little more engine braking, that’s all
As for how it drives: Until we started looking at the energy flow screen, we noticed that we were getting two quite different levels of engine braking. Once we looked at this screen, we noticed more pronounced engine braking during the time the capacitors were loading up, and a noticeably lower level of engine braking once they were charged.
Following the graphical loading of the capacitors on the screen with the corresponding It only took as little as about ten seconds, decelerating from highway speeds, for the system to charge up to full; meanwhile discharge rates seemed only a bit longer—when we were accelerating or climbing a hill, for example.