How to calculate Solar Panel Battery and Inverter power

knowledge

2025.02.17

knowledge

How to calculate Solar Panel Battery and Inverter power

Step 1: Calculate your Load
a. Power Rating
Different devices use different powers, which can be either peak or continuous. For example, a laptop can use around 50 watts. Similarly, a mini-fridge consumes 60 watts of power. A smartphone can charge at 10 watts.

How do you check the power rating?

•Some devices, such asphone chargers, have been shown on them. Thoroughly go through it.
•If you have a manufacturer’s manual, that works out well.
•Those who fail to explore both methods can find it online.

With the power rating, you can sum up all your data. For example, you are charging the following devices.
A laptop of 40 watts.
A ceiling fan of 60 watts.
The washing machine is 300 watts.
The total load will be the sum of all the three tools.
40W+60W+300W = 400W.

In addition, you can also make a statistical table to make statistics on the electrical equipment in your home, such as the table below:
Step 1: Calculate your Load
a. Power Rating
Different devices use different powers, which can be either peak or continuous. For example, a laptop can use around 50 watts. Similarly, a mini-fridge consumes 60 watts of power. A smartphone can charge at 10 watts.

How do you check the power rating?

•Some devices, such asphone chargers, have been shown on them. Thoroughly go through it.
•If you have a manufacturer’s manual, that works out well.
•Those who fail to explore both methods can find it online.

With the power rating, you can sum up all your data. For example, you are charging the following devices.
A laptop of 40 watts.
A ceiling fan of 60 watts.
The washing machine is 300 watts.
The total load will be the sum of all the three tools.
40W+60W+300W = 400W.

In addition, you can also make a statistical table to make statistics on the electrical equipment in your home, such as the table below:
Step 3: Calculate Battery Capacity
Measuring the battery capacity can help determine how many batteries you need for a 5000-watt power load.
There are two types of batteries commonly being used.
Lead Acid Battery
These are dominating the home sectors. Usually, one 150 ah can store an energy of 1800 watt-hours.
Capacity = 12 volts × 150 Ah = 1,800 watt-hours (Wh)
Batteries required backup time power /capacity.
Batteries required= 5000 watt-hours / 1800 watt-hours = 2.77≈ 3 lead-acid batteries
You would need at least three lead-acid batteries to empower your system.
Lithium-ion batteries.
These batteries are trending because of their excellent power supply and the few accident cases.
You can apply the above scenario to lithium-ion batteries. You might need one 150-ah battery. Here is the complete calculation of the data.
Capacity = 48 volts × 150 Ah = 7,200 watt-hours (Wh)
Batteries required= backup time power /capacity
Batteries required= 5000 watt-hours/ 7200 watt-hours = 0.69≈ 1 lithium-ion battery
One lithium-ion battery can meet your whole power supply demands.

Step 4: Calculate Inverter Capacity
They are necessary because solar energy storage is in DC form, while home appliances work at AC voltage.
Convert your DC into AC to meet your demands and turn on your devices.
First, calculate the power tolerance. It is often 20-25% of the total power load.
Suppose the above example of a power load. 5000 watts is the power load. The tolerance will be.

Tolerance = 1000 watt x 20/100 = 200 watts

The total power tolerance is 1000 watts. Now, calculate the inverter capacity for your required power load.
Inverter Capacity= Load + tolerance = 1000 watts + 200 watts = 1200 watts
You would need at least an inverter with 1.2kWh capacity. The capacity below this level can’t empower devices efficiently.

Step 5: Calculate Panel Capacity
solar panels don’t offer 100% efficiency in solar energy production. So, we’ll rely only on 80% of the output.

•Total power with backup time required.

We have already discussed it as being 5000 watt-hours.
•Calculation solar of 80% efficiency.

If the efficiency is 80%, then you can calculate it.
Power load with backup time ÷ efficiency
=5000 watt-hours ÷ 80/100
=6250 watt-hours
•Hours for sunlight they are charging.

Sunlight availability is necessary for solar panel charging. Not all solar panels remain in sunlight for 24 hours so that we will assume a value of 5 hours here.

•Required panel capacity

Once you have the sunlight timing, it is a no-brainer to calculate the solar panel capacity.
Solar panel capacity = 6250 Wh ÷ 5 hours = 1250 watts

Your solar panel capacity must be 1250 watts. You can use 100 watts, 200 watts, or even more wattage, but multiply the number of panels with the power. The total solar panel capacity must be equal to or sometimes greater than the required one.

A blind jump into solar technology can dump you down! So, relax. Understand all your power requirements at home or in commercial sectors. Measure how much power you need. Finally, you can explore the relevant solar solutions.

If you want premium-quality solar solutions, we have them. SUNUW POWER has all the solar solutions.
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