I used to work in the wind industry, so a couple of comments.
What some people fail to realise, or choose not to acknowledge, is that wind is a very constant and reliable resource. No one builds a wind farm without a significant amount of wind data for a site. 10 years is a good target, but sometimes it is done with two to three years data. You will find the usual variations are -20% in a bad year to +20% in a good year (much less than the variation fossil fuel prices). Understanding the wind resource and terrain modelling allows you to design the farm and place the turbines for maximum efficiency. "Turbines only generate energy when the wind blows" is something you see all the time. Once again, the resource is well understood before anyone commits to financing a wind farm. What you are looking for are sites with a high capacity factor. The capacity factor is a percentage of the installed capacity that you can reasonably rely on for "continuous" generation. So a 1,000 MW wind farm with a capacity factor of 35% should generate the same energy in a year as a 350 MW gas or coal or whatever power station. The developers and owners know that the wind pattern changes over the year and so may commit different tranches of power to the market at different times. For example, if you know the wind is stronger in say Spring, and less in Summer, you would look to forward sell energy on that basis (as opposed to the energy you trade on the spot market).
An ideal "battery" set up is to combine wind with pump storage hydro, so that the hydro give you the ability to sell power in the morning and afternoon peak with regularity, and the wind is used to provide energy to pump the water back to the upper storage. Of course the new massive Tesla batteries are changing that focus. The one installed in South Australia is essentially charged by renewables (wind) and is used to balance the grid and power essential services should the grid crash. It has a capacity of 193 MWh. It is estimated that the cost saving of using the battery to balance the SA grid saves around $40M/year. Batteries have issues no doubt, so do coal mines, oil spills and so on.