This lovely programme is available for a few days more and gives details about the Isle of Canna Electricity Generation Scheme. It shows the battery array inside the barn. This site gives more technical details. Whilst researching Shetland earlier in the month, I found a figure that says there is a requirement of 1MW power generation for 750 houses. Here there are maybe 10 households which would need a nameplate capacity of 13.3kW. Either the solar or the wind would easily cover this but for long foggy spells, there are the batteries. The programme quotes 130000kWh per year which is an average of 14.8kW across both day and night! The figure given of 30kW is roughly double that - accounted for by 12 hours of daylight and 12 hours of darkness on average.
