There are two ways to answer this question. The first is to determine how long solar cells can power your house. In many cases, if solar panels do not produce energy, a fully charged battery can keep your house running overnight. In order to make more accurate calculations, you need to know some variables, including how much energy your home consumes in a day, the capacity and rated power of solar cells, and whether it is connected to electricity. grid.
To give a simple example, we will determine the battery size required to provide an appropriate solar plus energy storage solution based on the national average data of the US Energy Information Administration. The average American household consumes about 30 kilowatt-hours (kWh) of energy per day, and a typical solar cell can provide about 10 kWh of capacity. Therefore, a very simple answer is that if you buy three solar cells, you can operate at home all day long as long as the batteries support it.
In fact, the answer is much more complicated. You will also use the solar panel system to generate electricity during the day, and the system will provide powerful electricity for approximately 6-7 hours of the day during peak sunshine hours. On the other hand, most batteries cannot operate at maximum capacity and usually peak at 90% DoD (as described above). Therefore, your 10 kWh battery may have a usable capacity of 9 kWh.
Ultimately, if the battery is paired with a solar photovoltaic array, one or two batteries can provide enough power at night when no panels are produced. However, if there is no renewable energy solution, you may need 3 or more batteries to power the entire home for 24 hours. In addition, if you want to install home energy storage equipment to disconnect from the grid, you should install a few days of backup power to solve the possible cloudy days.