Fortune: Here's Why Ocean Shipping Companies are Switching to Natural Gas

The North American ocean carrier TOTE is deploying the world’s first container ships fueled by liquefied natural gas (LNG). The move anticipates imminent environmental regulations that are likely to trigger large shifts in the maritime shipping industry.

TOTE is making the move to comply with the international Marpol Annex VI maritime emissions standards, first implemented in 2005. Restrictions on emissions like sulfur and nitrogen oxide will tighten in 2016 within designated emission control areas (ECAs), including the waters surrounding North America.

Sulfur and nitrogen oxides are generated in large volumes by conventional maritime ships, which have long relied on so-called heavy fuel oil—the thick, dirty, but affordable remnants of the crude oil refining process. According to the International Council on Clean Transportation, the ocean shipping industry currently accounts for 8% of global emissions of sulfur dioxide, which causes acid rain. MORE