Inverter is usually an integral part of our solar panel system, many people know that his working principle is to convert DC to AC but may know very little about the number of batteries it needs, and how to run it, now let’s learn about it together.

1. How many batteries are needed for a 3000W inverter?
Generally speaking to calculate how many batteries are needed for a 3000W inverter, we can take a step-by-step approach. First, we need to know the rated voltage of the battery, since voltage * current = power. We can get the required current first. Current * time = total capacity. Then we can get the number of batteries by taking the total capacity/battery capacity.
For example, there is an existing battery with a rated voltage of 12v. 3000/12=250A, and if the usage time is 5 hours, we can get the capacity of 1250Ah by calculation, so the 3000W inverter needs to be equipped with 10 pieces of 12v 125Ah batteries. Or 5 pieces of 24v 125ah batteries. If the output efficiency of the inverter is taken into account, the number of batteries required may have some variations.
2. How should we choose the battery type?
Lead-acid batteries and lithium batteries are generally popular nowadays. Lithium batteries are more expensive, but have a high energy density, use less volume when storing the same amount of energy, and have a long service life. Lead-acid batteries are cheaper but weigh more and have a shorter life span. My suggestion is to try to choose lithium battery if you have enough budget.
3. What can a 3000W inverter run?
The higher power of 3000 inverter can take more loads when in use, below are some power needed by power equipment can provide reference.

Air conditioner: 800W~4600W
Refrigerator: 70W~800W
Energy-saving lamps: 9W~50W
TV: 50W~200W
Laptop: 60W~70W
Microwave oven: 900W~1200W
Electric fan: 20W~70W
Washing machine: 300W~1100W
Rice Cooker: 500W~1200W
Hair dryer: 600W~2000W
Referring to the above data, if the power consumption of the power-using equipment exceeds the maximum output power of the inverter when the inverter is loaded, it is recommended to use a higher power inverter.
4. How many solar panels need to install 3000W inverter?
In some solar panel systems, we only need to consider the power of the inverter and the power rating of the panels. We can take the maximum input power of the inverter directly as the total power generated by the solar panels. For example, if we use solar panels with a power rating of 400W, then when we use an inverter with 3000W, 3000W is the total power of the solar panels, and in order to meet the demand, no more than 7 solar panels should be installed to meet the demand.
5. Conversion efficiency of the inverter
For almost all electrical devices, it is difficult to reach 100% efficiency, and the same goes for inverters. According to the data given by the inverter manufacturer, most of the inverters can reach 80%~95% conversion efficiency when they are used at the beginning. However, as the inverter is used for more time, its current conversion efficiency will gradually decrease.