Mazda's Breakthrough in Engine Technology

The petrol engine’s days might be numbered, but that hasn’t stopped Mazda announcing a breakthrough that could make it up to 30% more efficient. Mazda is calling its new discovery Skyactiv-X – although the industry term for it is Homogeneous Charge Compression Ignition or HCCI for short – and it could spell the end for diesel.

How does it work?

Although it’s odd to have a petrol engine breakthrough in 2017, cracking HCCI has always been a holy grail, and it essentially works by making a petrol engine behave more like a diesel one.

Right now, conventional petrol and diesel engines differ in one key way. Both detonate a mixture of air and fuel to generate kinetic energy and petrol engines do it using compression and a spark plug. By contrast, diesel engines can trigger this explosion by using compression alone.

HCCI engine technology doesn’t always need spark plugs to cause these explosions, and that means it’s more efficient. And because it produces fewer Oxides of Nitrogen emissions (NOx), it’s also less harmful to the environment.

Mazda says the engine will still be fitted with spark plugs as HCCI will only possible under certain conditions, but it’s still a huge breakthrough.

What does it mean for the petrol engine?

While petrol engines might be dead within the next 50 years, Mazda’s HCCI breakthrough could speed up the death of diesel – and possibly increase the sales of hybrid vehicles. Diesel is already facing a sharp decline, and if the new engine is as efficient as Mazda says it is, the main point of getting a diesel car will have basically been erased.

Mazda is hoping to get the technology into its road cars by 2019, and although it recently committed to developing EVs with Toyota, it’ll still have an impact in the car sector, at least for the next 30 years.

"We think it is an imperative and fundamental job for us to pursue the ideal internal combustion engine," said Mazda’s R&D head Kiyoshi Fujiwara. "Electrification is necessary but... the internal combustion engine should come first."

Mazda has always been something of an oddball in relation to the car industry. First it persevered with the incredible, but inefficient rotary engine, and now it appears that it never really gave up on developing the petrol engine, either.

Interestingly though, Mazda currently has no plans to share its new breakthrough with its competitors – even though it could be better for the environment, and petrol technology as a whole.