Complex sentence: In the U.S., Rifkin was instrumental in founding the Green Hydrogen Coalition, consisting of thirteen environmental and political organizations (including Greenpeace and MoveOn.Org) that are committed to building a renewable hydrogen based economy.
Split into simpler sentences: In the U.S., Rifkin was instrumental in founding the Green Hydrogen Coalition. The GHC consists of 13 environmental and political organizations (including Greenpeace and MoveOn.Org) that are committed to building a renewable hydrogen based economy.