Thinking of investing on solar power? Are you wondering can you power your home with solar panels? We can help answer that.
On average solar panels can be used to power your home. Knowing how many solar panels one needs is the key to the system being successful. You will need to divide your kwh usage for a year divided by the number of days in a year to get your daily production of solar needed. This is assuming you want no power bill.
The answer isn’t exactly the same for everyone so read on so that you can understand.
1. Calculate The Number Of Solar Panels To Power A House
To calculate the number of the amount of solar power that you will need for your home. You will first need to look at your power bill. The question is can you power your home with solar panels? On your power bill you will have an annual kilowatt hours used. Most homes on average use anywhere between 10000 kWh and 14000 kWh per year.
You would take this number and divided by 365. This will give you the daily usage of kilowatt hours. Alternatively you can look on the side of your power bill and sometimes they will have it marked as your daily usage right on your power bill. Whatever your daily usage is you’ll need to divide that by five. So for example if your daily usage is 38 kWh. Divided by five. This would be 7.6 kWh or 7600 W.
Now to get into more of the math. Why do we use the number five?. The number five is the average amount of sunlight hours per year per day. So the more northern hemisphere it is as low as 3 and south of the equator it is as high as 8 however we will use five for this example. Five is the amount of sunlight hours in the run of the day over 365 day. This includes cloudy days rainy days snowy days etc. So this is why we use the number five. Again talking to our math or talking if we take W or 38 kW divided by five this would be 7.6 kW or 7600 Watts. Now 7600 watts is it decent size solar system.
The solar panel wattage size is based on per hour of production.
2. Use Solar Panels To Eliminate Your Electric Bill
You can use solar panels to reduce your power bill. You can do this by using a process called net metering which is usually available by your local power utility. Net metering is when you sell back your excess of solar production to the grid. This will offset for days that you use more. Like cloudy days or rainy days.
At the end of your power bill cycle you should see a credit. However you will need to size properly to make sure that you have the right size system. You can use example above to size your system if you’d like to have a net zero power bill or no power bill at all. Some areas of the world will even let you produce more than what you use resulting in either a credit or a check back to you directly to the customer.
3.Can You Use Solar Panels During A Power Outage?
There are two types of solar panel systems. A Grid tie system where you sell back. This prevents you from having any power when the power is out. It’s designed so it sells back to the grid when it is on as a safety precaution it must shut down when the grid goes out. So during a power loss or outage your solar system was shut down as well and will not be producing.
This is to make sure that no power is pushed back onto the grid for the safety of the utility and provider.
The other type system is where an off grid inverter takes a solar energy and converts it into household electricity. In this case you would have power during a power outage as this is a completely standalone system and you can use it to generate power.
These types of systems are good in areas where the grid is not accessible. In addition to that if you do have the grid and you choose to go this way you can still use the power from your solar system when the power is out. Just keep in mind you are a battery maintenance with this process with this type of system.
4.Can You Live On Solar Power Alone?
As a whole you can live on solar energy alone. However you will need to make some lifestyle changes and some smart decisions. Realistically how much money do you really want to spend on solar to get you through the couple slow months per year.
When we mean the couple slow months we mean November, December and January when the sun is at its lowest in the sky. You may size the system correctly for most months of the year however for those few months it may be hard to produce energy.
The opposite end is it is if you size it correctly for the slow winter months then you have an abundance of way too much solar have way too much solar energy in the summer. You could sell this back if you were in the right area and can strike the right agreement with your power utility provider. However due to the upfront cost most people just size them for the main part of the year.
There’s a slow parts of the year they subsidize their solar with alternative fuel sources like natural gas or propane to run their fridge freezer stove dryer or any other major appliance that you may need to consider is a lot of electricity.
5. How Many Solar Panels Will I Need?
Using our example above to provide 7600 watts to electricity or 7.6 kW you would need to supply 7.6 kW of solar panels.
The average size solar panel is between 200 watts and 400 Watts. If you go with the largest 400 Watt solar panel this result in close to 19 panels on your roof. Also keep in mind that these panels are 4’ x 8’ in size. This results in 32 ft.² of roof space for each solar panel.
You will need to measure the structure or the roof were you planning to install the solar panels to see if 19 of these will fit. 19 solar panels at 32 ft.² or solar panel is a lot of square footage almost 620 square feet to be exact.
6. The Number Of Solar Panels To Run Off Grid
The number of solar panels to run off grid varies depending on your needs. Most people start out with a smaller solar systems and then add to it as they see fit. Most of the smaller off grid systems we have done or usually only about 5 kW. 5 kW or 5000 watts is a good starting point for your off grid solar project. Keep in mind that you’ll have to subsidize this with some form of natural gas or propane for things like your hot water, stove, etc.
Battery maintenance also comes in to play with off grid solar make sure that you have the proper amount of good quality batteries for your solar system. We tend to sell customers more batteries and need it for storage purposes especially with off the grid to help them make it through the cloudy days.
Solar production can be combined with other sources like hydroelectric power or wind power to charge the batteries. The heart of the system would be your batteries in your inverters sending power back to your house. The amount of solar panels varies depending on size. Usually 24 to 36 solar panels a smaller size 100 W or smaller or sufficient enough to get you started. The voltage on the solar panels is a little bit lower than grid tie as we usually do 48 Volt systems.
7. Complete Solar Power Kits For Homes
One can purchase a complete solar system off the Internet. There are majority of links on Amazon and eBay which you can purchase these from. Can you power your home with solar panels from the internet?These are usually small starter system just to get you in the market. A couple thousand watts is about all you’ll see if you get a grid tie system or if you get an off grid system.
With the grid tie system you can usually get the grid tie inverter included in the kit. Make sure the inverter is approved for your area, as an example CSA or UL as well as CE approvals. If you get into an off grid system it will most likely include the inverter in the online kit however the batteries usually come from a separate source due to the weight and it is harder to ship them.
In the solar kit you should also get a charge controller to regulate the power to your batteries and possibly some MC for connections for plug and play.
8. How Much Roof Space Do I Need
If you’re talking on grid or off grid solar in either case you will need a lot of space. You can simply take the physical dimensions of the panels and multiply them to get your square footage. Once you have that you can figure out the square footage of your roof to see how many panels you can fit on.
Note that you should only stick the solar panels on the south facing side of your roof. These are the angle to the sun solar panels are the most productive. Also check out to make sure you get the proper mounting racks so you get air clearance of at least 2 inches between the solar panels and the roof shingles or roof space. This is important to not overheat and cause issues with shortening roof life.
Prematurely replacing a roof can be a costly project you do not want to endure.
9.How To Calculate The Payback Period
Your payback. Would vary depending on the amount that you pay for the solar system installed. You must include labour costs in this and any necessary permits to have the equipment installed on your home. You would simply just take the total amount to have it installed divided by the power production. This will offset the cost of your power bill and let you know your payback. Here’s an example of a payback. Below.
Ricky has 10000 watts of solar a panels installed on his house. He paid $20,000 dollars for them installed and running. He produces $12.50 per day on average so this would be times 365 days per year for a total of $4,562.50. But wait he uses $3000.00 per year in power.
So $4,562.50 minus $3000.00 is $1,562.50. If you take his $20,000 he paid for them and divide it by his surplus back to the grid of $1,562.50 this would equal out to a 13 year payback to have the system paid for.
10. Will They Be Worn Out After I Pay For Them?
Most solar panels generally have a warranty for up to 20 to 25 years. This warranty is a prorated as a percentage and runs out after the 25 years. Solar panels have a life expectancy of 35 to 40 years and sometimes even longer in the right conditions. Most likely they will not be worn out after you’re done paying for them. Especially if you have an aggressive payment plan to pay them off quickly.
We hoped this article helped educate you a little bit in making you decision on can you power your home with solar panels. Please check out our other topics on this website.