"ethanol engine" is correct and usable in written English.
You can use it to refer to an engine that runs on ethanol fuel, such as a flex-fuel engine. For example, "My car has an ethanol engine and can run on gasoline or ethanol."
"The good news is that a promising suite of technologies — ranging from flex-fuel ethanol engines to plug-in hybrids to hydrogen fuel cells — finally offers a way to move beyond oil and the internal combustion engine," Carson and Vaitheeswaran write.
Six years later, approximately 75% of Brazilian passenger cars were manufactured with ethanol engines.
This technology allows the controller to regulate the amount of fuel injected and spark time, as fuel flow needs to be decreased and also self-combustion needs to be avoided when gasoline is used because ethanol engines have compression ratio around 12 1, too high for gasoline.
One of the drawbacks of the use of hydrous ethanol in neat-ethanol engines is the increase in aldehyde emissions as compared with gasoline or gasohol.
In the early 1980s, vehicles with neat-ethanol engines that could use hydrous ethanol became highly attractive to consumers, as the government had ensured the pump price of hydrous alcohol would be equivalent to 64.5% of the gasoline price.
They include a design for a new liquid oxygen-ethanol propellant engine and replacement of guidance systems for several surface-to-air missiles.
The use of high water content hydrous ethanol in engines has the potential to significantly improve life-cycle energy use and CO2 emissions of bio-ethanol.
The Urbee uses electric motors, backed up by a small ethanol-powered engine, and is capable of 200mpg.
In the 1890s, Henry Ford came up with the Ford Quadricycle, a vehicle made up of a frame mounted on four large bicycle wheels with an ethanol-powered engine.
