Improved diesel hybrid engine

I am always interested in things that can improve propulsion power. A recent innovation comes from a group of Swiss researchers. They have developed a natural gas-and diesel-powered hybrid engine that they claim emits half the CO2 of equivalent conventional systems. The Engineers at ETH Zurich redesigned a VW Golf diesel engine to run on 90 per cent natural gas. But unlike traditional gas engines, the new design is ignited by a small amount of diesel injected directly into the cylinder rather than a spark plug.

At the same time, although I love gadgets, I have a healthy instinct for the 'KISS' principle. (Keep It Simple Stupid) when it comes to engines. We have an Audi car that we pay almost nothing for when it comes to road tax. Yet at the same time it requires a computer plugging in to resolve any of the computer systems warning alerts! 

But I digress - 

By continually monitoring and adapting the injection using pressure sensors and control algorithms, the researchers say they have increased the engine’s efficiency to a maximum of 39.6 per cent. This gives it a fuel consumption of 3.2 litre per 100km or 88.3mpg for the latest VW Golf diesel model’s. Compared to 2.4 litre per 100km or 117.7 mpg for the new engine. Which works out at an extra 30 miles per gallon of fuel.

Natural gas-diesel engines already exist and are not a new technology. However this kind of engine arrangement is typically used in industries where power is generated and used in the same for example, to operate large machinery. As Tobias Ott, a doctoral student at ETH who worked on the project explains 'In a vehicle, the engine speed and load are changing constantly, which in turn means the engine management system is far more complicated.'

But while the idea of a gas diesel hybrid is a good one. The main aim is to reduce emissions  reducing emissions requires computers and sensors. Therefore the control system is going to be very complex. The researchers are concentrating on increasing the temperature in the catalytic converter by modifying control of the engine during the warm-up.

As Tobias Ott explains 'Our combustion engine converts heat energy into mechanical energy with such efficiency that the exhaust gas is not warm enough to create sufficient heat, particularly after start-up.' The researchers also linked the engine to a small electric motor to further reduce fuel consumption. Dr Christopher Onder, another of the engineers involved, said he believed the engine could be readied for series production in five years.

So it could be awhile before we see a marinised version for boats.