@Prague
A watt is a unit of power, i.e. a measure of energy per unit time. A watt-hour is a unit of energy corresponding to an ongoing production or consumption of one watt over a time period of one hour.
The confusing statement in the story is:
"The State of California estimates that it requires 55,657 gigawatt-hours of new renewable energy generation to meet its clean air and water standards, according to a report published by California?s Independent System Operator (ISO) in March."
Here we have an energy requirement with no reference to a time period. Is this energy needed each year, each day or over a ten-year period? Without a reference time period it is impossible to translate this requirement into a corresponding generating capacity. What percentage of the requirement could be met by the Alta Wind Energy Center?
