"Overall, those numbers indicate that something must be displacing our use of fossil fuels.

"Overall, those numbers indicate that something must be displacing our use of fossil fuels. That something was clearly not nuclear, which held steady over the last year. This leaves us with renewables."

https://arstechnica.com/science/2018/03/renewables-conservation-start-pushing-fossil-fuels-off-the-us-grid/
https://arstechnica.com/science/2018/03/renewables-conservation-start-pushing-fossil-fuels-off-the-us-grid/