The Mazda MX-5 Miata is getting the company's i-ELOOP regenerative "braking" system in more overseas markets. A few months ago, the company announced it for the Japanese market, and this week it announced the U.K. will have the feature, too. This has us curious as to whether it will be offered on U.S. market Miatas. We've reached out to Mazda, and we'll update this story if and when we hear back.
As a quick refresher, i-ELOOP is a system that was introduced here on the Mazda6 several years ago, and it adds a capacitor to store electricity generated by the alternator during deceleration (hence our earlier use of quotes around "braking") that can be used to run interior accessories such as the sound system and climate control. Then, with power coming from the capacitor, the alternator can be disengaged, improving the efficiency of the engine by reducing drag. And by using a capacitor rather than a battery, the system is more compact, lighter and able to recharge faster than a similarly capacious conventional battery.
As for effectiveness, the Mazda6 with i-ELOOP managed to get about 5% more miles per gallon on the highway than one without, going from 38 mpg to 40 mpg. While not a massive improvement, it was a measurable, possibly noticeable one. Applying a similar gain to a Miata would increase fuel economy from 35 to nearly 36.75 mpg on the highway, based on the automatic-equipped car's numbers. The manual would go from 34 to nearly 35.7.
The i-ELOOP system is standard on all new Miatas in the U.K., which includes the 1.5-liter and 2.0-liter engines with either the manual transmission or automatic. Strangely, only automatic-equipped cars get it in Japan. This means Mazda could offer it on both transmission options in the U.S. Probably the key consideration will be cost. The system, when it launched in the U.S., was only available on the most expensive Mazda6, and even then it was an extra-cost option. And looking at pricing for the U.K. Miata soft-top and comparing equivalent trim levels, the price has increased between £2,800 and £4,100. The new model does get some new standard safety features, too, but we expect the i-ELOOP system is a significant contributor. If it is offered in the U.S., it might only be available as an option, and possibly only on the more expensive trim levels to keep lower trims more affordable.