Diesel engines may rank number one when it comes to internal combustion efficiency (there are about 50 models of diesel engines available to customers today), but their use isn’t necessarily the best for the environment. The EPA has established standards that limit the amount of sulfur contained within diesel fuel, which allows it to burn cleaner.
In accordance with that restriction, the International Maritime Organization has placed a new cap on sulfur quantities in fuel oil in the hopes of significantly reducing the amount of sulfur oxide emanating from ships (which should have major health and environmental benefits for the world, particularly for populations living close to ports and coasts). As a result, many engineers are trying to find a viable solution to keep within the sulfur limit.
ABS, a company that provides “classification and technical advisory services to the marine and offshore industries”, has just announced their success in converting a diesel engine into one that runs off of ethane. If you know your gas molecules, you’ll know that ethane is categorized as a natural gas liquid (NGL), along with propane, butane, isobutane, and pentane. Propane and butane are frequently burned for fuel; it wasn’t believed that ethane could do much of anything in that field until ABS created Navigator Aurora.
Ethane is a low flashpoint fuel, meaning it vaporizes at relatively low temperatures. The converted engine in Navigator Aurora burns this vapor for engine fuel, which significantly reduces the need for gas re-liquefaction during voyages. The environmentally-friendly engine is also more efficient because it takes less power to run. Paul Flaherty, Director of Fleet and Technical operations at Navigator Gas, explained the significance of this.
“This project represents a significant investment… that clearly demonstrates a very strong commitment to environmental protection and the reduction of greenhouse gas emissions. This retrofit modification will comply with all current global emissions regulations and position us as early adopters of the global sulphur cap regulation due to come into force on the 1st of January 2020.”
If more vehicles, including cars, could utilize this important conversion, global emissions would be greatly reduced.