Nowadays, solar energy system has become an indispensable power generation equipment for many families, therefore, an in-depth understanding of how to calculate how long it takes to charge a solar battery is conducive to your rational planning of your home’s electricity consumption, and for the purchase of solar batteries can also provide a theoretical basis for the purchase of solar batteries, Solar light manufacturers also rely on these calculations to design efficient and reliable products. In order to calculate how long it takes for your solar battery to be charged, you need to first start with the following key data.
1. Wattage of solar panel (W)
If you only have one solar panel, you only need to input the rated wattage of this solar panel into the calculator, of course, if you need to calculate the system formed by connecting multiple solar panels, then you need to add up the rated wattage of all the solar panels in this system and input it into the calculator, i.e.:
Number of solar panels x wattage of individual solar panels = total wattage of solar panels
For example, assuming you have 20 units 200w solar panels in your solar system, according to the above formula, you can enter 4000 into the solar panel wattage column of the calculator.
2. Solar battery Capacity (Ah)
Each solar battery has a fixed battery capacity, such as common solar lithium batteries have 40Ah, 48Ah and 54Ah, etc. You can easily find the capacity of your solar battery from the instruction manual of the solar battery.
3. Rated voltage of solar battery (V)
The rated voltage of the solar battery refers to the maximum safe voltage for your solar battery to work, the manufacturer will specify this value according to the structure of the solar cell when manufacturing the solar battery, the common rated voltage of the solar battery in the market is 12V, 24V and 48V, etc. You can find this data from the instruction manual of the solar battery provided by the manufacturer.
4. The type of solar battery and its depth of discharge
The type of solar battery is also one of the key factors affecting the charging time of solar battery, because different solar battery have different depths of discharge, the depth of discharge refers to the ratio of the maximum amount of electricity that can be discharged by the battery to the capacity of the battery, for example, the depth of discharge of lithium batteries is generally 80%, while the depth of discharge of lead-acid batteries is generally 50%.
Of course, in time is the same type of different solar batteries, the depth of discharge will have a certain difference, the solar battery charging calculator takes this into account, you can rely on the instructions for solar batteries will be the depth of discharge of your solar batteries into the calculator, which can make the final results more accurate.
5. Types of solar charge controllers
Different solar charge controllers have different power loss during the charging process of solar battery, obviously, the charging time of solar charge controllers with high power loss during the charging process of solar battery will be longer. There are many types of solar charge controllers on the market, such as PWM and MPPT, etc. Under normal circumstances, the power consumption rate of solar charge controllers is between 5% and 10%.
6. How to Calculate the Time Required to Charge a Solar Battery
After getting the above data, you can calculate how long it will take to charge your solar battery. Calculating this result through the formula requires multiple steps, in order to give you a deeper understanding of the whole calculation process, here is an example to help you understand the calculation formula.
Assuming that the total wattage of the PV panels of your solar system is 2000watt, the capacity of your solar battery is 80Ah, and its rated voltage is 12V and the depth of discharge of the battery is 80%, because only off-grid and hybrid solar systems have solar battery, and the conversion efficiency of these two solar systems is 85%, the final power consumption rate of your solar charge controller is 5%.
First of all, you need to start by converting the battery capacity of your solar battery from Ampere hours to Watt hours, ie:
Watt-hours (Wh) = Amp-hours (Ah) x Voltage (V)
Substituting the data gives you 960Wh for your solar battery.
Then, you need to know how much you need to charge your solar battery, i.e.:
Solar battery Charge (Wh) = Solar battery Watt-Hours (Wh) x Solar battery Depth of Discharge
Substituting the data gives you a charge of 768 Wh. Immediately after that, you need to calculate the output power of the solar panel:
Output power (W) = total watts (W) x conversion efficiency of the solar system x (1 – charge controller’s power consumption rate)
Substitute the data to get the output power of your solar panel is 1615W, and then finally divide the solar battery charge by the output power of the solar panel to get the charging time, i.e.:
Charging time of solar battery = charging amount of solar battery (Wh) / total power of solar panel (W)
Substitute the data to get the charging time of your solar battery is about 27 minutes.
7. Advantages of Solar Battery Charging Time Calculator
As you can see from the above calculations, there are many formulas to calculate the charging time of solar batteries. If you want to rely solely on formulas to calculate how long it takes to charge your solar batteries, it will not only take a lot of time and energy, but also difficult to guarantee the correctness of the final rate.
Solar battery charging time calculator can help you solve this problem, the calculator has a specific algorithm, you only need to fill in the data to the corresponding column, the calculator will immediately give you the correct answer, so you can greatly save your time, become a big help in your life.
