Toyota has developed a 2.0-litre, four-cylinder petrol engine that is said to have a thermal efficiency of 40 percent – just 1 percent short of what the Prius offers with its 1.8-litre hybrid powertrain.
Toyota states that the engine can achieve unparalleled levels of fuel economy as a result of new friction-reducing technology and more efficient exhaust and cooling systems.
In general, petrol engines have a thermal efficiency of about 20-25 percent.
The new 2.0-litre petrol engine, which peaks at 171hp, will also get hybrid electric power. In this guise, it will match the Prius’ 41 percent thermal efficiency but with more performance thanks to its larger capacity.
Toyota has also developed a more efficient CVT gearbox that uses the world’s first gear drive for initial acceleration. This essentially gives the gearbox the quicker off-the-line response of a standard automatic but enables the higher efficiency of a CVT when moving.