A natural gas-diesel hybrid engine has slashed CO2 consumption to less than half.
Developed by researchers at ETH Zurich, the internal combustion engine has managed to achieve fuel consumption of less than 2.4 litres per 100 km.
The incredible efficiency has been created by igniting the engine with a small amount of diesel fuel injected directly into the cylinder instead of using a spark plug. The rest of the combustion process was fuelled by natural gas. As a result, maximum efficiency was recorded by the Swiss scientists at a very high 39.6%.
The challenge scientists faced was how to overcome the constant changes in engine speed and load. They used a sensor to measure pressure in the cylinders and then used control algorithms to adapt continually the amount and timing of diesel injection, thus creating the efficient engine performance.
Consumption was further reduced by linking a natural gas-diesel engine to a small electric motor. According to the research team, the system can also be used in a vehicle without electric hybridisation.
The scientists who have developed the engine are hopeful it will be possible to mass produce it within the next five years and are already in negotiations with a car manufacturer.