Solar panels are the power-generating solution for the future. They use solar energy, which is a renewable resource. If you think that solar panels are only for hotels and industries, then you must rethink because numerous people and large residential areas are installing solar panels. Not only using solar panels is a clean energy production method, but it also helps you save thousands of dollars that you pay on your utility bill every year. Well, if you are thinking about how many solar panels and batteries to power a house, read ahead. Not only this, but you will also get to know how to Calculate how many solar panels you need for your home.
How Many Solar Panels and Batteries To Power A House?
Solar panels are widely used nowadays due to their high productivity and obviously the reason that using them results in lowering electricity bills. But since everyone has different types of houses that largely vary in size also, the type of solar panels and the number of batteries required also change largely. These factors determine the number of solar panels you need for your house.
1) Average (Monthly) Solar Power Generation in Your Area
The average monthly solar power generation can vary depending on the region you live in. In some regions, you get 5-6 hours of sunlight whereas some regions enjoy 8-9 hours of sunlight, while some have even more sun hours. Depending on the sun hours, average monthly solar power generation can range between 80 kilowatts per hour and 130 kilowatts per hour.
Note: The above-mentioned range varies based on the intensity of sunlight in summer and monsoon.
2) Average (Monthly) Power Consumption of Your House
The next thing that matters to know how many solar panels and batteries to power a house is the power consumption. Now you have to calculate the average power consumption of your house by adding the power consumption from the last 12 months and then dividing the sum by 12. Remember, you need to add the power consumption units and not the amount of money.
3) Number of Batteries Required
Usually, solar panels are backed up by a battery bank which sources the house when there is a shortage of sun hours. The number of batteries you need depends on the following reasons.
- Number of Batteries: An average American household can be powered for 3 days with a battery bank that provides about 90 kilowatt-hours of electricity. To provide 2.4 kilowatts of electricity you will need a battery bank with 38 batteries. But if the power produced by batteries is less or more, the number of batteries may vary depending on it too.
- Power Consumed: 1 kilowatt of energy is equal to 1 hour of 1 kilowatt or 10 hours of a device with 100 watts. Suppose you use 901 kilowatt-hours per month of energy, it is equal to the 30 kilowatt-hours of energy consumed per hour.
- Specification of Batteries: Certain voltage is produced depending on the ampere-hours of the battery. For example, a 400-amp-hour battery can provide 4 amperes for 100 hours of current. The standard working voltage is increased by amp-hour to measure the battery capacity in kilowatt-hours. This is another factor to determine how many solar panels and batteries to power a house in any area.
- Time period: It defines the number of days you want your solar panel to last with a battery backup. Sometimes when there are not enough sun hours, the solar panels work on the stored energy in the battery bank. But these batteries will sooner or later get exhausted if there is no primary supply of energy to your house or solar panels.
Also See: 8 Best Rechargeable Batteries for Solar Lights
How Long Will Solar Panel Last?
Usually, the average life span of a solar panel is 25 years (300 months) or more. They are designed to withstand the extremes of harsh weather and last long. Your solar panel will come with a minimum warranty of 25 years. Solar panels last 80% longer than their warranty, as per the study conducted by the National Renewable Energy Laboratory. This means you get the benefits for 33 years by paying for 25 years.
Why Should You Get A Solar Panel For Your House?
The reasons are endless, but here is the list for you to consider if you are still confused about whether you should get a solar panel.
- Ever-increasing electricity rates across the nation influence your budget
- A chance to make long time savings with one investment
- A house with solar panels has more resale value (if you consider selling).
- You get to enjoy huge tax credits from the government and some states are offering rebate programs too. Interesting information in the process to know about how many solar panels and batteries to power a house.
- You get a fourth-of-the-decade warranty, that is 25 years warranty on solar panels.
Also Read: Can a 300 Watt Solar Panel Run a Refrigerator?
How is Power Generated From Solar Panels?
Solar panels convert light energy into chemical energy which then gets converted into electrical energy. Here are the steps involved in the working and power generation of solar panels.
- They absorb sunlight.
- The light absorbed is converted into direct current (DC) power.
- This direct current is converted into Alternate Current (AC) by using an inverter (hybrid or micro)
- The electricity thus generated is transferred from wires into your house.
- Everything connected to the panels via wires is powered with the current.
- If there is an excess of electricity generation than what is consumed, the extra energy will be stored in the electric grid.
What Are The Different Types Of Solar Panels?
Here are the basic 3 types of solar panel systems available.
1. Grid-Tied System: This is the most common system for residential houses and is wired directly to your house and the utility grid. This connection allows you to easily switch between solar power and general power. It is considered the most affordable among the three systems.
2. Grid-Tied System with Battery Backup: This system is connected to the house and utility grid, but this one is backed by battery backup. Any excess electricity produced is stored in the battery bank and is used when there is no power generation at night. How many solar panels and batteries power a house depends on the type of batteries too.
3. Off-Grid System: This system is not connected to the utility grid. The connection is given only to your house and to the battery bank. This system essentially is backed up with a battery bank which is why it is the most expensive.
Which Factors Affect The Number Of Solar Panels Required By the House?
Solar panels collect energy when there is sufficient solar energy. This means your need for solar panels depends on various factors related to your house.
1. Angle of Inclination – It is an important factor in power generation because the position of the sun changes during summer and winter. Therefore, choosing the best angle is necessary where the inclination is the most in all seasons.
2. Dust and Snow – The solar panels are exposed to dust and snow other than the sun. A thick layer of snow or dust can become a hurdle in the path of the sunlight toward the panel.
3. Orientation – The ideal orientation of solar panels is towards the equator for them to receive maximum sunlight. So, if you are from a country in the Northern Hemisphere, your solar panels must face toward the south and vice versa.
4. Shadow – Certain objects, like trees, poles, other buildings, etc, all cast a shadow on your solar panels if your house is not as high as them. This results in blocking sunlight and reducing power generation. Make sure to place solar panels in places where they receive at least 4-5 hours of sunlight. How many solar panels and batteries power a house is influenced by the above factors too.
Also See: Can Portable Solar Panels Get Wet and Still Work?
How To Calculate How Many Solar Panels You Need For Your Home?
Here are the steps to follow for calculating the number of solar panels or batteries you need for your house.
Step 1: Find out your average daily electricity usage.
Step 2: Learn how many peak sun hours your specific location gets.
Step 3: Now, pick a solar panel power rating. This rating varies from 250W to 450W.
Step 4: Calculate how many solar panels you need for your home by using multiplying all of the above three values.
Total number of solar panels needed= daily electricity usage x peak sun hours x panel wattage
Let’s understand this with an example,
Suppose, your daily electricity usage is 40,000 watt-hour. The average peak sun hours is 5 hours and the average panel wattage is 400 watt.
The number of solar panels you need for your home= 40,000 watt-hours/5 hours/400 watt= 20 solar panels.
So, you’ll need 20 solar panels to power your house.
Also See: RV Solar Panels and Solar Kits – Beginners Guide
How To Calculate How Many Solar Panels You Need For Your Home Per Area?
If you are installing solar panels for your home on the roof or terrace, you need to know the area of the roof and the number of solar panels that will fit into it. Did you get the point about how many solar panels and batteries to power a house? The average size of all solar panels is above 300 watts, which is 2 meters by 1 meter (6.5 feet by 3.25 feet). This size can cover about 2 square meters (21.50 square feet).
Area required for solar panels = Total number of solar panels multiplied by the area of one panel
If for a 7.8 kW system, you need 24 solar panels, then you need an area of-
Area for 7.8 kW of solar panels= 24 * 21.50 = 516 square feet
Here is the table for you to refer to for the area required to install a solar system.
|Size of Solar System||Number of Panels (330 watts)||Area Required|
|1 kW||3||65 square feet – 90 square feet|
|2 kW||6||145 – 180 square feet|
|3 kW||9||205 – 270 square feet|
|4 kW||11||193 square feet|
|5 kW||12||285 – 450 square feet|
|6 kW||17||270-280 square feet|
|8 kW||22-25||580 – 720 square feet|
|10 kW||30||750 – 900 square feet|
How Many Solar Panels Do I Need For 1000 Kwh Per Month?
The answer to this depends largely on the fact where you live and what the power rating of your solar panels is. However, to calculate the number of solar panels for 1000 kilowatt-hours per month you need to know your-
- Monthly electricity usage
- Power ratings of the solar panels you are considering
- Monthly peak sun hours (1 peak sun hour = 1000 watts per meter square of sunlight)
Monthly electric usage * 1000 / monthly peak sun hours divided by power rating of the solar panel
Now, an example for you to understand it better.
Electricity consumed = 893 kilowatt-hours
Peak sun hours = 5.2 per day = 31*5.2 = 161.2 peak hours in the month
Considering it in 1000 = 1000 kilowatt-hours / 161.2*1000 = around 6203
The power rating of solar panels = 400 watt
6203/400 = 15.50, rounding to 16.
So, you need about 16 solar panels for 1000 kilowatt-hours. This is another important info to understand how many solar panels and batteries to power a house.
How Much Will A 1000 Kilowatt-Hour Solar System Cost You?
After learning how many solar panels do I need for 1000 kwh per month, you should also explore how much will a 1000 kilowatt-hour solar system cost you. Different countries have different price slabs. Overall, in the US you can expect the prices to be as per the following table.
|Size of the System (in kilowatts)||Average Cost ($) (without tax credit)||Average Cost ($) (After tax credits)|
How Much Kw Solar Panel Required For Home Appliances?
It depends on the type of appliances you are willing to use on solar power. Here you can refer to the following things to understand how many panels you need for the same.
4 bulbs = 15 watts each = 60 watts
1 fan = 60 watts
Running Time = 4 hours
Sunlight = 6 hours
Begin with calculating the total watts used:
Total watts = 60 + 60 watts = 210 watts
Now, this is the total energy required from the solar panel for your appliances for continuously 4 hours.
Calculate the power required per day:
Solar Power required daily = 120 watts * 4 hours = 480 watts-hours per day
Calculate the power charge required for appliances from the solar panel:
Power required = 480 watts / 6 hours of sunlight = 80 watts per hour
Therefore, you will need a solar panel that can provide power of 80 watts per hour for the above appliances. Other things like battery backup, inverter, and charge controller sizes may differ and are not considered here. With this, you have learned how much kw solar panel required for home appliances.
How Many Solar Panels Do You Need For a 1500 Square Foot House?
The average bill received for a house of 1500 square feet is about $100 per month. To calculate the number of panels you can calculate by the formula mentioned. How many solar panels and batteries to power a house of 1500 square feet? However, as per rough calculation, your house may need about 15-18 solar panels. This can vary depending on the location, sun hours, and power consumption of your house.
Also See: How to Use Solar Panel Directly Without Battery?
How Much Does It Cost To Install the Solar Panels?
The costs for installation vary, but you can take an average of around $15000 and $30000. You do not have to pay this hefty sum of money in one go because companies offer you financing and other incentives to lower the burden.
Now, you know how many solar panels and batteries to power a house. How many solar panels do I need for 1000 kWh per month? The answer to this is based on the amount of energy received by solar panels. How much kw solar panel required for home? To know this, you need to know the energy consumption, solar power generation, along with the power of the solar panels. Calculate how many solar panels you need for your home and get a solar panel this holiday season for your house.
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