Mazda made a game-changing fuel efficiency breakthrough other carmakers have spent decades working on

As soon as 2019, Mazda will have a petrol-driven car in production that is cheaper to run than a Tesla Model S.

The Japanese carmaker has announced it is ready to reveal a combustion engine using compression technology Ford, General Motors and Hyundai have been trying to get into production for the best part of a decade.

It’s called Spark Controlled Compression Ignition and it uses the same sparkless technology used by diesel engines, without the high emission rate.

At low revs, the SkyActiv-X employs sparkplugs to ignite petrol, but it switches to compression ignition at high revs. Mazda claims it can handle the switch without engine damage.

If its claims of a “20-30%” increase in fuel efficiency are true, then the 2019 Mazda3 – the model most likely to get the first SkyActiv-X engine – could be running on as little as 3.5L per 100km.

At today’s fuel prices in Melbourne, that’s $19.25 for 500km, which is about the maximum range of a full battery in Tesla’s Model S.