Ten US states including California in 2017 generated more than 20% of their electric power from wind and solar including small-scale PV, evidence that grid operators are having increasing success with integration of renewable resources, according to Energy Information Administration (EIA) data.

The 10 states were Iowa with 37% of electricity generated from wind and solar; Kansas (36%); Oklahoma (32%; South Dakota (30%); North Dakota (27%); Vermont (24%); California (22%); and Maine, Colorado and Minnesota – all 20%.