Does it at least use a TVM calculation? If so it's indeed quite misleading, considering that at max 1 cycle per day (e.g. solar) that's 6 years to spread the cost across.
If the battery storage is directly connected to the DC side of a solar farm, that's one charging opportunity per day. If it's just hooked into the grid, two charging opportunities per day would be more typical in California. Wind power output tends to be highest at night after the daily demand peak is already past.
Look at yesterday (11 July 2019) on the renewables trend graph, for example.
Wind reaches its daily minimum around noon, while solar is peaking. Wind's maximum output is at 10:00 PM, long after the sun has set and after the demand peak has passed.
