• 05.06.11

The Gas Engine Is Not Dead Yet, Thanks To Diesel, Jaguar

Despite the ongoing rush of alternative-fuel tech, the gasoline engine’s having a moment thanks to advances from Jaguar and the Department of Energy.


Despite the ongoing rush of alternative-fuel tech, the gasoline engine’s having a moment thanks to advances from Jaguar and the Department of Energy.


Jaguar CX75 million-dollar hybrid

Last year Jaguar teased an incredible concept car, the CX75, that had an electric engine in each wheel and a pair of high-performance gas turbines in its truck to provide the electrical power. Now the luxury car firm has decided it’s actually going to turn this dream of eco-friendliness(ish!) into a real production car, albeit a ridiculously high-end one. Only 250 of the cars will be built with the help of Formula 1 team Williams, starting in 2013, and will rock in with a price tag close to $1 million. 

At first, the cars will use a conventional gasoline engine–your typical small-scale four-stroke unit with a turbocharger–to spin a generator powerful enough to drive the all-wheel electric motors. The car could, of course, be run from batteries…but at the kind of performance the car’s designed for they wouldn’t last very long. That’s because this is less of an eco car, and more a proof of concept “it could be green if we wanted it to be” machine. With a 0-60MPH time of a scant three seconds.

The best bit? You’d know that as well as turning heads with the sleek looks and what’s sure to be awesome sound of the thing gliding along, you’ll be able to drive your million-dollar supercar with a relatively clear conscience. It’s a hybrid, after all.

Gasoline-plus-diesel design wins

The battle between gasoline-powered internal combustion engines and diesel-powered ones goes right back to the invention of the engines themselves. Diesels are much more fuel efficient, but are rarer in the U.S. because by the very nature of their design they pump out more nitrous oxides and hydrocarbon pollutants. Gasoline powered engines are thus de riguer in the U.S., while diesels are more common in Europe, where there are slightly laxer anti-pollution laws. The thing is, gas engines are often only around 20% efficient in turning fuel into miles driven, while diesel engines can reach around 40% fuel efficiency–which actually challenges some of gasoline’s eco-cred.

Now research by the Department of Energy and the University of Argonne in France has suggested there’s a way to combine key parts of diesel technology into gasoline engines, pushing their fuel efficiency up to around double what it is today (and with gas-guzzler SUVs roaring across the U.S., going twice as far as before for each buck of fuel spent sounds pretty tempting). 


The trick is that gasoline engines work by injecting fuel into the cylinders, then compressing the fuel-air mix and igniting it with a spark plug. Diesels simply compress the air, then inject the fuel under pressure–the fuel/air mix is actually self-igniting (like hypergolic rocket fuels), which results in a more efficient burn and thus greater fuel efficiency–at the expense of nitrous oxide production and soot due to the way the flame propagates through the air-fuel mix.

Now the science team has worked out that it’s possible to inject gasoline directly in much the same way, building up enough fuel density to spontaneously ignite the mix by repeatedly pushing in puffs of fuel, rather than the single squirt a diesel fuel needs. It’s a relatively simple adjustment to the design of engines, and it could give the gasoline engine a much-needed kick of extra life before the all-electric revolution kicks in. In fact, it could even significantly boost the eco-cred of hybrid car designs. There’s only one drawback–the power output of the gas engine is slightly decreased, meaning Americans would have to forgo their muscle-cars.

Chat about this news with Kit Eaton on Twitter and Fast Company too.

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