Solace Integrative Supplies has created and manufactures integration systems for different power supplies. They have a range of industrial storage batteries for excess power which can be modified for specifically requested inputs and outputs. Single household batteries that can store and emit 13.5 kWh of power a day start around £5,500. Larger sized batteries that can output around 50kWh of power in a day start at roughly £20,000.
The average house in the UK (household of 2 adults and 2 children) uses between 2800kWh and 4000kWh a year in energy, averaging to roughly 7.6kWh to 11kWh a day. (7.6 being a mid terraced house, and 11 being a detached house)