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Considering the average American home uses 900 kwh a month, 3000 kwh is a way lot more. But that is exactly what you would expect if you own a farm or a large property. Despite the immense power requirement, you can still run everything solely on solar power.
You need 64 to 69 solar panels to produce 3000 kwh per month, and each must be 315 watts. The required number drops to 58 to 60 if you use 375 watt panels.
How Many Solar Panels For 3000 Kwh a Month?
The guideline above will work, but there are a lot of variables involved here. How much of the power do you want to run from solar? Are you on the grid or off it? Do you own a large house or a farm? Where do you live and how many sunlight hours do you receive?
You can ask a solar panel provider to conduct an assessment on your property, but you can do it yourself using the following information. You can then determine how many solar panels you will need.
The formula is average sun hours per day x 30 / kwh per month = solar panel size
If you need 3000 kwh per month and the property receives 5 hours of sunlight a day, that would be 5 x 30 = 150.
3000 / 150 = 20. You need at least 20 kwh, or better yet 21.5 kwh to offset energy losses.
If you want solar power to produce 80% of the power, multiply kwh per month by .8.
3000 x .8 = 2400. You need 2400W to convert 80% of your monthly energy usage into solar.
Whether you own a house or a farm, calculating how many solar panels you need is the same process. The numbers given here are examples, so you can substitute whatever numbers you require.
How to Calculate Energy Cost for a 3000kwh System
Add your total energy bill for the previous 12 months to get the yearly total. Get the average monthly bill as well. The national average cost is 13.3 cents per kilowatt, but the rate can vary widely. Louisiana has the lowest average at 7 cents, while in Hawaii it is 29 cents. So if you consume 3000 kwh, the bill will be way higher in Hawaii than Louisiana.
Once you get the total, you have an idea how much you pay and how much solar can save you. You can decide what percentage you want to run off solar and how long before your investment pays off. Buying a solar panel is an investment and will pay off, the only question being how long.
The more you use solar, the more you benefit. No matter where you are, those kilowatts are going to cost you some every month. With inflation, you will pay more every year for using the same amount of energy. With solar, you can avoid inflation.
How to Calculate Energy Usage
Calculate how much energy in kwh you use a year and the average monthly total. Note we say average because you probably won’t be using 3000 kwh every month.
You might use more power during the summer for the AC, fans, etc. or you might spend more on heaters during the winter. If you own a farm, the energy cost will likely be tied to the needs of your livestock and poultry.
Bottom line is your usage will be less than 3000 kwh in some seasons and higher during others. If you are going for a hybrid or grid tied system, you have to know when your energy consumption is highest so you can offset that with solar power. If your usage goes up to 3200 kwh or more during the summer, you can reduce the cost with a solar array (several solar panels joined together).
Should You Go 100% Solar Power on a 3000kwh System?
If you want to go 100% solar, you must have a battery bank or access to solar buyback or net metering as your energy usage will vary season by season. Without any of these you could waste solar power production.
Suppose your house needs 3000 kwh during the summer and 3300 kwh during the winter. If your system generates 3200 kwh during the summer, the extra power goes to waste. On the other hand, production may drop to 2900 kwh during the winter, falling short of what you need.
Solar panel ratings and output differ, and when you add the changing weather you could end up with an overabundance or lack of solar power. There are two solutions, net metering and solar batteries.
Net metering or solar buyback is a program that allows you to sell excess solar energy to the power company in exchange for credit. If you produce an extra 200 kwh in July, you can sell it to the utility company. When your system production drops in November, you can use the extra credit and get electricity without paying a higher bill.
The benefit of net metering or solar buy back is no energy is wasted. Your solar system can produce more than 3000 kwh a month and you can use that as credit for later use.
If you do not have net metering, you can buy batteries for energy storage. Batteries will add to your cost, but with it your solar system can produce whatever amount and the extra gets stored. You can even go off grid with a large battery bank and an inverter
If you do not have net metering and do not want to buy solar batteries, the best recourse is to install a solar array that meets 80% of your total power needs. This assures you won’t over produce and waste energy. If production comes up short in certain months, you have to use the utility grid.
What battery capacity should you use? It depends on your solar panel production. Once a solar power system is installed, you should have an idea of when production is high and low. Calculate how much energy your solar panel fails to meet during low production months, and use that as a guide for the battery size.
3 Factors That Affect Solar Panel Performance
The calculations that solar panel manufacturers provide are based on ideal weather conditions. In real life sun intensity and angles changes all the time, one day you have excess power, the next day it could be lower. There isn’t much you can do about the sun, but these other factors you can manage.
Shading and Blocking
If you own a farm and it is surrounded by trees, make certain they do not block solar panels. Whether on the rooftop or ground, trees and buildings could block the panels and slow down energy production. If you have a solar system monitor, you can check the performance and if you notice a dip, check for blocking or shading.
Trees are not the only culprit. Dirt, bird droppings, bird nests and other debris could be all over your solar panels. And it doesn’t take a lot of those to affect performance. Fortunately, cleaning solar panels should do the trick. You can do it yourself, but for such a large solar array it is better to call a solar cleaning company.
As pointed out in our article solar panels for 1500 kwh a month, region plays a major part in determining how many solar panels you will need. The Midwest and hotter regions in the US generate more solar power than the colder areas, so you have to factor that in.
If you live in the northwest for example, you may have to add more solar panels – or use higher wattage – to make up for the climate. In the same manner you could probably get away with fewer panels in the Midwest. But this again depends on your setup and what percentage you want for solar and for the utility grid.
Solar Panel Quality
Buy from a reputable solar panel company, that is the bottom line. Solar energy cost has gone down, but buying a 20 kw system will still cost thousands of dollars. You are planning for the future here, spending now to reduce power costs in the future.
Just like any investment you have to do your homework. In this case that means buying from a company that has established itself already. You can only reap the benefits of solar power if the panels are of high quality.
By quality we mean a high efficiency rating (preferably 20% and higher), durable, with a long, comprehensive warranty and customer support. This will take some time, but you should do the work now and save yourself the trouble later on.
Installing solar panels require planning, even more so when the power requirement is 3000 kwh or more. While installation is best left to a solar panel provider, you have to do your part in planning so you can supply them with the essential information. Whether you opt for 315W, 375W or 400W, being prepared will make the setup process easier.