These types of reports that solar power is achieving historic low prices is a con. It is achieving low wholesale prices but due to cost shifting retail electricity prices are soaring in those states that have shifted to solar power. Cost shifting means the costs of redundant natural gas power, grid coordination, new transmission lines and imported balancing power needed during sunset hours of the day are not counted in the wholesale cost of power. That is why prices are reported dropping on solar power farms but not on rooftop solar panels on residential structures where it remains uneconomic without subsidies.
The Sacramento Municipal Utility District is one of the largest producers of hydroelectricity in the state. In 2015, a dry year, it pegged its costs for hydro at 3.2 cents a kilowatt hour, compared to 6.1 cents a kilowatt hour for natural gas.
Its not unusual to see hydro projects across the country coming in at 2 cents a kilowatt hour.
When it comes to the average retail price of electricity, California finishes sixth-highest in the country and fourth-highest for states in the continental U.S., at 15.42 cents a kilowatt hour.
http://www.latimes.com/business/la-fi-hydropower-rain-20170307-story.html