Energy stored in your batteries is accessible in two ways. Direct access is available for appliances designed to operate on 12v DC current. However, many appliances require 110v AC power (like those in your house).
To convert the current in your batteries from DC to AC you’ll need an inverter. This device makes it possible to run your AC devices. These are rated in watt output.
A 1500 watt inverter can operate most small appliances requiring about 10amps AC current such a TV, coffee maker, laptop, computer, radio, lights, etc. To get more current you’ll need a higher wattage inverter.
Note that the type of inverter must be paired with a properly sized battery bank so as not to discharge the batteries too quickly. Also, the size of solar array is not affected by your inverter size. The solar array size should be chosen based on the amount of energy you’ll consume in a given day. An inverter needs to be sized on the max draw on your batteries at a given time such as how many things you’ll be
powering at once.
Your inverter will need be able to meet maximum draw at a given time. This mean adding up all of the current being drawn at once from all of the appliances which are powered on simultaneously. If you’ll be vacuuming with the lights on and your laptop charging you’ll need to know the entire current draw of these appliances to size your inverter. If your inverter is too small it will have to run less appliances at one time.