Rocky Mountain Institute’s Shipping Efficiency Operation was originally launched in 2010 by Carbon War Room—a global non-profit founded by Sir Richard Branson and a group of likeminded entrepreneurs that merged into RMI in 2014. Rocky Mountain Institute (RMI) is an independent nonprofit founded in 1982 that transforms global energy use to create a clean, prosperous, and secure low-carbon future. RMI engages businesses, communities, institutions, and entrepreneurs to accelerate the adoption of market-based solutions that cost-effectively shift from fossil fuels to efficiency and renewables. RMI has offices in Basalt and Boulder, Colorado; New York City; Washington, D.C.; and Beijing.

Together with RightShip, Rocky Mountain Institute manages the GHG Emissions Rating, which ranks vessels against others of a similar type and size on a simple A to G scale, from most to least efficient. It is now used by charterers to shift a fifth of the world's shipped tonnage to more efficient ships annually and by other shipping stakeholders, including ports and banks.