On and off. Bruce Woodman on overcoming intermittency in renewables for long-term, low-cost energy
There is a difference between intermittent and unpredictable. While wind and solar are intermittent, their short-term output and annual average over the next 25 or more years can be very accurately predicted.
If a site can host a mix of renewable energy production, intermittency can be smoothed, and its impact reduced.