Breaking up is hard to do — and bad for the planet too, says new research. Divorce rates around the world are rising, with the consequence of multi-person homes dissolving into multiple residences, which use more land, water, and energy. Ecologist Jianguo Liu, publishing in the Proceedings of the National Academy of Sciences, concluded that in 2005 in the U.S. alone, divorced households used 73 billion more kilowatt-hours annually of electricity and 627 billion gallons more water annually than would have been used if folks had stayed hitched. “People have been talking about how to protect the environment and combat climate change, but divorce is an overlooked factor that needs to be considered,” Liu said. Sure, “some people really need to get divorces,” he says. But “one way to be more environmentally friendly is to live with other people and that will reduce the impact.”