液化天然气
Some cruise lines have also taken it upon themselves to reduce air pollution, by using alternative, cleaner energy sources which has positive implications for marine waters as well. Shorepower (cold ironing), battery power, fuel cells, and liquified natural gas (LNG) are among sources that are being explored. Carnival Corporation is one example of a cruise liner that is currently pursuing cleaner energies. In 2016 Carnival announced that it had agreed to partner with Shell and utilize LNG to power its next two new ships. Liquefied natural gas, a fossil fuel, is a much cleaner source of energy than oil and also much less expensive, to the benefit of cruise companies. Transitioning away from oil will help cruise liners combat their problems with bilge pollution. Cruise ships efforts to reduce their waste, recycle, and find more renewable energies will help alleviate their current rate of pollution of marine waters.