What size battery suits me?

Start from what you use between sunset and the moment the panels start producing again the next morning. For most households that falls between four and ten kilowatt-hours. That is immediately the order of magnitude of a battery that gets fully used every day.

An electric car that charges at home.

A heat pump, certainly in winter.

Electric cooking and a large household.

The wish to keep going during a power cut; that calls for additional provisions.

A household that is home during the day and therefore already uses a lot directly.

Few electrical appliances in the evening.

A small solar installation that produces too little in winter to fill the battery.

A battery is filled less often in winter than in summer, simply because there is less sun. Anyone calculating purely on the basis of a summer day buys too big.

On top of that, a lithium battery never discharges to zero per cent. That is not a fault but a safety margin: full discharge damages the cells. What you see is the usable capacity.

ADW works out your evening usage and proposes a battery to match. If it turns out a battery would gain you little, we say so. We would rather not sell a battery than sell one that stands half empty.