Effective Capacity per Battery = 10 kWh x 90% = 9 kWh Number of Batteries Required = Total Energy Needed ÷ Effective Capacity per Battery = 30 kWh ÷ 9 kWh = 3.33 This implies that a UK household would require at least 4 lithium-ion solar batteries to sustain their energy needs for three days without any solar input.
Considering a popular Lithium-ion battery that offers a 10 kWh capacity with a 90% DoD: Effective Capacity per Battery = 10 kWh x 90% = 9 kWh Number of Batteries Required = Total Energy Needed ÷ Effective Capacity per Battery = 30 kWh ÷ 9 kWh = 3.33
For a solar photovoltaic (PV) system of 5 kW with a daily energy consumption of 5-10 kWh, a 4 kWh battery is recommended to maximize returns, while a 35 kWh battery is advised for those looking to maximize energy independence.
Then, divide by thirty to get a rough estimation of your daily energy use, and you’ll be able to work out what size battery is best for you. If you use 8 kilowatt hours (kWh) per day, then you’ll need a battery with a capacity of at least 8 kilowatts (kW) to provide all of your energy needs during the day.
This implies that a UK household would require at least 4 lithium-ion solar batteries to sustain their energy needs for three days without any solar input. Solar Panel Output: Ensure your solar panels produce enough energy to charge the batteries.
To work out what size battery you’ll need, you can start by calculating your electricity usage. Look at either your smart meter or your monthly energy bill, which will tell you how much you use on average. Then, divide by thirty to get a rough estimation of your daily energy use, and you’ll be able to work out what size battery is best for you.