This Promising Engine Uses Both Gasoline and Diesel in Your Vehicle

Imagine buying a car where the engine allows you to get the best of what gasoline and diesel can offer. The result: an extremely thermally-efficient engine that leads to increased engine power, better fuel efficiency (especially for low emission semi-trucks and off-highway vehicles), and cleaner emissions.

Its name? The Reactivity Controlled Compression Ignition engine--or RCCI for short. Developed by the University of Wisconsin-Madison labs, this concept engine has shown a lot of promise, and has the potential to be far-reaching in scope.

How it Works

It works by using two fuels that are opposite in their combustion speed: a low-reactivity fuel (such as gas) and high-reactivity fuel (such as diesel) are mixed together. This isn't limited to gasoline and diesel, but they're the ones used because they're the most common today.

It's similar to the four-stroke engine system, but with more components mixed in. It starts by mixing standard gasoline and air inside the combustion chamber during the intake stroke, then injecting in diesel during the compression stroke, and then adding more diesel as the piston comes closer to the top. This sets off an ignition, igniting the gas, diesel, and air mixture inside.

Advantages and Disadvantages of the RCCI Engine

The combination of these gases allows the vehicle to convert 60 percent of fuel into workable power, which is a huge figure compared to average cars that fall somewhere between 40 to 50 percent. And since its thermal efficiency is also high, then less fuel is wasted and less noxious and soot emissions are generated in the process. What's more, this engine also reduces heat transfer losses, fuel cost, and  costly after-treatment systems.

With all these benefits, are there disadvantages to using it? For one, it can mean adding separate fuel tanks and lines, which can weigh the car down. What's more, it means filling up on both diesel and gasoline whenever you stop over for fuel. That can be inconvenient, and can waste time in the process.

Still, we stand by the RCCI. Let's wait and see how the University of Wisconsin-Madison labs improve and refine this concept engine over the coming years.