Groundbreaking Mazda Skyactiv-X petrol engines to be ‘cleaner than electric’


Car maker set to produce world’s first compression ignition petrol engine, with well-to-wheel emissions that beat electric vehicles

Mazda has pledged that its next generation of petrol-engine vehicles will be cleaner than electric cars due to the use of efficiency-boosting compression ignition technology.

In an announcement earlier today, the Japanese brand said it is developing Skyactiv-X engines, which are set to replace the current Skyactiv-G range in 2019. The technology was previously only used in diesel engines. Mazda claims the results improve efficiency by up to 30% over its current petrol units, matching or even improving on the brand’s Skyactiv-D diesel engine range.

Mazda said this will enable Skyactiv-X engines to produce lower emissions than electric drivetrains, when their life from well-to-wheel is accounted for.

Compression ignition technology has not yet been used on a mass production scale in petrol engines. The so-called Spark Controlled Compression Ignition system mixes petrol and air together in the engine’s cylinder like a regular spark ignition engine, but then ignites it using compression as well as a spark. This means around half the volume of petrol is required for the same combustion level.

Mazda director Kiyoshi Fujiwara explained that this “very lean air-fuel mixture that is too lean to combust by spark ignition [alone] can combust by this method cleanly and rapidly”, adding that this enables «better thermal efficiency, improved fuel economy and lower nitrogen oxide emissions». Other benefits include higher efficiency across a wider range of revs, thus improving engine responses and performance.

The company has pursued this technology because it believes spark ignition technology is fast reaching its peak. Mazda also argues that electric technology, while green at the tailpipe, has yet to represent a truly sustainable option on a global scale, since much of the world’s electricity grids are still powered by fossil fuels.

As part of its so-called Sustainable Zoom-Zoom 2030 plan, Mazda has pledged to reduce corporate average well-to-wheel CO2 emissions to 50% of 2010 levels by 2030, before reducing them by 90% by 2050.

The company will begin introducing electric technology into its range from 2019, but has stated that it will focus sales of these models in regions where sustainable energy is produced. It will continue to invest heavily in petrol technology beyond this point, citing a continued growth of combustion engine demand in other regions, such as developing economies.

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Source:: Autocar