One of America's largest utilities, Xcel Energy, yesterday announced plans to switch to solely carbon-free electricity by mid-century, as part of a sweeping new "clean energy vision".
As well as providing only carbon-free electricity to customers by 2050, Xcel also promised to reduce emissions to 80 per cent below 2005 by 2030.
The goal is a boost from its previous target of a 60 per cent cut, and Xcel claims its targets are now the most ambitious announced to date in the US electric power sector.
In a statement CEO Ben Fowke said Xcel took the decision to ramp up its climate goals in light of the rapid breakthroughs in clean energy in recent years and a sharp rise in the number of customers asking for greener power.
Xcel Energy is Colorado's largest energy supplier, and the state's Governor-elect Jared Polis welcomed the "exciting" news, adding it will help towards the state's ambition of building a "renewable and clean energy future".
Polis wants Colorado to phase out all fossil fuels from its electricity system by 2040.
Xcel Energy said it believes its 2030 target can be achieved using renewables and other technologies that are already available, but warned its long-term vision of zero-carbon electricity will need new technologies to be developed and reach commercial viability.
"Our goals are ambitious and achieving them requires a long runway," Fowke added. "We're starting the conversation today to make sure we can achieve this groundbreaking transition while continuing to keep energy affordable and reliable for customers."