Calculations are tricky but without them, it is hard to estimate and keep things under budget. The same goes for the solar power system too. The amount of sunlight received per square meter on the solar panels determines the output you will receive from the solar panel system. So, if you are planning to get a solar panel system for your house, it is better to understand the solar power per square meter calculator. Also, you will learn about solar panel area per kW.
What is the Solar Panel Output?
The amount of electricity generated by the solar panels for a given period of time is known as the output of the solar panels. Under ideal sunlight conditions and temperature represent the theoretical power production of the solar panels. The time period can be 1 day, a month, or a year. The overall output varies from manufacturer to manufacturer, factors affecting the productivity of the solar panels, etc. The output is expressed as kilowatt-hours (kWh).
Solar Power Per Square Meter Calculator
The amount of solar intensity received by the solar panels is measured in terms of square per meter. The sunlight received per square meter is termed solar irradiance. As per the recent measurements done by NASA, the average intensity of solar energy that reaches the top atmosphere is about 1,360 watts per square meter. You can calculate the solar power per square meter with the following calculators.
1. For Off-Grid
It is the system that generates its own power with panels and a battery bank. In the off-grid calculator select from the option, shed cabin, house, or portable. Next, select the days of full autonomy, etc.
2. Solar Savings Calculator
Note down the basic details on a paper and then select the accurate answer asked by the calculator.
Factors to Consider for Solar Panel Output Per Square Meter
- Region: If you are living in countries near to poles, you will receive less sunlight. In comparison to the people living in regions near to the equator. Also, the weather condition prevailing in your region
- Power of Panel (Watt Peak): Solar panels are marked with watt peak (Wp), and this is the amount of output the panels should produce in ideal conditions. Your solar panel will give more output if it has a higher watt peak.
- Slope: If you have a solar tracker then it is easy to adjust the direction of the panels in accordance with the position of the sun. Depending on the Slope of the house, the angle of the solar panels should be between 20° and 50°.
- Direction: Suppose you live in the Northern Hemisphere. In such a case, you have to place the panels where they are facing south.
- Time of the Year: With the help of the solar panel calculator, you can calculate the output even on winter days. The calculator helps you to calculate the average output for the whole year. This average output is calculated by breaking down the monthly output at your location.
- The Efficiency of Other Electrical Systems: A solar panel system is not only about solar panels and sunlight. It also includes wiring, inverter, charge controller, and battery bank (if used). A solar power per square meter calculator takes details regarding these factors and then gives the accurate output generated by the solar panel per square meter. After this, it’s time to learn about solar panel output calculators.
Also Read: How Many Batteries Can a 50 Watt Solar Panel Charge?
Solar Panel Output Calculator
Wattage is the output of solar panels that is calculated by multiplying the volts by amps. Here, the amount of the force of the electricity is represented by volts. The aggregate amount of energy used is expressed in amps (amperes). Output ratings on most solar panels range between 250 watts to 400 watts.
1. Number of Solar Cells
The most common categorization of solar cells is in 60-cell solar panels and 72-cell solar panels. The former one means there are almost 60 solar cells in the solar panels and the latter determines the usage of 72 solar cells. There is an extra row of solar cells in a 72-cell solar panel system. The higher number of solar cells means a higher absorbing surface area for sunlight, resulting in more output.
2. Size of Solar Panel
The 60-cell solar panels are 5.4 feet long and 3.25 feet wide. They possibly give an output of about 270 watts to 300 watts. They are suitable for residential areas. The size of a 72-cell solar system is the same, just they have an extra row of cells. The average output from 72-cell solar panels ranges between 350 watts to 400 watts. They are used in commercial solar projects and large buildings.
3. Efficiency of Solar Panels
This is an important indicator when using the solar power per square meter calculator. A solar panel with high efficiency produces more output. The conversion rate of silicon-based solar panels is between 18% and 22% of the total sunlight received by them. It led them to exceed 400 watts of power. The solar panels with the highest efficiency up till now were developed by the National Renewable Energy Laboratory (NREL). It has 39.5% efficiency.
4. Environmental Factors
These factors influence the output because solar panels are placed outside the house, mostly on the terrace. They are continuously exposed to different weather conditions. Here are the factors that alter the output of solar panels.
- Sunlight Hours: Different regions experience different amounts of sunlight and have distinct sun hours. The solar panels are exposed to sunlight for an average of 4-6 hours a day. The output of the solar panel depends on the time period for which the sun shines on the panels. However, the intensity of the sun is also taken into consideration here.
- Peak Sun Hours: The intensity of sunlight is not the same throughout the day. The sun is hottest during the peak hours, which is mostly from noon till 3 pm. However, these peak hours reduce during winter and rain. Sometimes, there are hardly any peak hours because it is cloudy. Thus, the power of sunlight determines the amount of energy absorbed by the solar panels and output on the same.
- Shade: Solar panels need direct sunlight but due to photovoltaic cells the solar panels charge the batteries without direct sunlight. This is why you are able to use the solar power system during winter. But if a part of the solar panel system is covered with shade or is under the shade then the output of that portion reduces. Since the cells are connected to each other, the reduction in the output of one panel affects the overall output of the solar panels.
- Inclination: The orientation and inclination of the solar panel system also affect its output. The angles of the solar panels should be adjusted such that they receive the most sunlight throughout the day. A perfectly angled solar panel will have good output as compared to one that is not inclined and angled properly.
Impact of Solar Panel Output on Its Cost
The output highly affects the cost of the solar system. Costs vary from location to location and your energy needs. The average output of solar panel systems available in the market in kilowatts is 3, 4, 5, 6, 7, 8, and 10. You can calculate the cost in your area by finding the average cost per watt in your area. Then multiply it by the solar panel output.
Also See: What Size Charge Controller for 200W Solar Panels?
Solar Panels kWh Calculator
Here, a kilowatt-hour is the total amount of energy used by a household during a year. The calculator used to determine the solar panels kWh needs the following details.
Energy usage (per year) in kilowatt-hours
Solar or sun hours (per day)
Percentage of electricity bill to offset
Open the calculator and enter the details.
- Energy usage should be without any commas.
- For sun hours refer to this map
For example, I will use the following dimensions to determine what the output in kilowatt-hours would be.
Steps to Calculate:
Electricity usage = 300 kilowatt-hour
Sun hours = 5 hours
Percentage of offset = 80%
Solar array size Estimate = 0.18 kilowatt
After this, let’s learn about solar panel area per kW.
Also See: How to Check If Solar Panel is Charging Battery?
Solar Panel Area Per kW
To consider the kilowatt required by the solar system, you need to use the average monthly consumption. Suppose you use 1400 kilowatt-hours per month, and the average sunlight is 6 hours.
Now using the calculation,
1400 / 6 * 30 = 7.7 kilowatt
This is the energy for an hour and in terms of the solar panel system, you will need a system with 8-140 kilowatts.
The number of solar panels does not define whether they will fulfill the energy needs of your house or not. Focus more on the total output provided by solar panels. To determine the number of solar panels you need for the solar panel system, you can use the following equation.
Number of panels = system size / single panel size
Here, the system size and panel sizes are the wattage. Also, the system size determines the power output expected from the solar panels. However, the number of panels required depends on the following factors:
- Solar panel needs
- Usable roof area
- Dimension of solar panels
- The efficiency of photovoltaic cells
Well, today you learned about the solar power per square meter calculator and the factors that you need to note down while doing the calculations. Solar panels kWh calculator will help you determine the kilowatt by using units from monthly electricity usage, sun hours, and offset percentage. I hope this will help you in determining the correct units.
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