How Many Solar Panels Do I Need Calculator

The Energy Requirements For Your Home

The first thing you need to do is take a look at how much energy your home uses. You can do this by taking past electricity bills and looking for an average usage. You will want this to be a daily average, so if your bill does not show this then divide it accordingly. So, if it is monthly, divide it by 30, and if it is annual, divide it by 365. Your answer will also be in kilowatt hours . This is how much power you are using at any given time, multiplied by the total time the power is used for. So, if you run a 60w light bulb all day, you will be using around 1,440 watts, or 1.4kWh.

Factor : Your Daily Power Usage Kwh Per Day

Yes, were back to your power bill again. But were also getting closer to the number you want to know how many solar panels will you need.

Task 5: Divide your average monthly power usage by 30 days.

Use your expected average monthly power usage that you determined earlier to calculate your average daily usage. If youre using 1000 kWh per month, thats 33 kWh per day. Youll want this number to help determine how many solar panels youll need.

How Much Money Can You Save With Solar

As you can see from the results in the solar calculator, a solar power system can save you a lot of money on your power bills. The average size solar system we are now installing is around 8kW-10kW, or to basically fill the roof with panels where roof space is a limitation. The main reasons for this are:

• Good quality solar systems generate power at well less than 10 cents per kWh, often around 5 or 6 c/kWh. Because of this, many households are installing the largest system they can fit on their roof
• With an over-sized solar system, many of our customers are enjoying a credit on their power bill every quarter
• Government rebates are still in place, and the larger the system, the larger the rebate
• Property prices are increasing at such a rate that many households are using the equity in the property to replace their power bills for the coming decades. A good quality solar system can also add value to a property as long as the right brands are used
• Batteries have completely changed the market. Whether you buy one now or in the future its advisable to get your solar system installed now with the presumption that you will store excess solar power at some stage in the future in a battery. This means sizing up a solar system based on your 24-hour usage, and until you get the battery installed you will get paid a good feed-in tariff from your energy retailer

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Assess How Much Sunlight You Get In Your Area

Youll need to calculate how many peak solar hours you can expect to receive on an average day where you live. This number reflects an average day because some days are sunnier than others, and because sun exposure is longer and more direct in summer than in winter.

The number of peak solar hours you receive will vary widely depending on where you live. A home in sunny southern California gets far more sun exposure than one in northern Michigan, which has more cloudy days. Further, time of day is significant the intensity of sunlight is different depending on whether its 9 a.m. or 12 p.m. or 4 p.m. as is the angle at which the suns rays are reaching a solar panel.

Technically, a peak solar hour occurs when the intensity of sunlight reaches 1,000 watts of energy per square meter. This sounds complex to figure, but, fortunately, science has done this difficult research for you so you dont have to work this out for yourself. Researchers have determined peak solar hours for any part of the U.S., and the data are readily available. Most parts of the U.S. receive 3 6 peak solar hours per day.

To begin calculating how many solar panels youll need, first determine the number of peak solar hours you receive in a month. To do this, simply multiply your peak solar hours x 30 :

4.6 x 30 = 138 solar hours

Find How Much Energy Solar Panels Produce In Your Area

Now that you know how much electricity your home uses in a month, you need to find the amount of sunlight your area receives. This is usually measured in something called “peak sun hours”, which is essentially the intensity of sunlight in your area.

We have a complete list of the average number of daily peak sun hours for each state. This is how much sunlight your area receives daily, be we need to know how much you receive monthly. To do this, simply multiply your states daily peak sun hours by 30. On average, the U.S. receives between 120 and 150 peak sun hours per month.

The monthly peak sun hours you get tells you how many kilowatt-hours of electricity 1 kilowatt of solar panels will produce in your area in one month. So, if your state receives 150 monthly peak sunlight hours, 1 kW of solar will produce 150 kWh of electricity per month.

Not sure about the differences between kW and kWh? Read our guide about kW versus kWh and what they mean.

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Amount Of Direct Sunlight In Your Area

Where there is more sunlight available, there is more energy that can be converted into electricity. The yearly output of each solar panel is higher in states like Arizona or New Mexico, which get a larger amount of sunlight than less sunny regions like New England.

The World Bank has created solar radiation maps for over 200 countries and regions, including the U.S. The map below can give you an idea of the sunshine available in your geographic location. Keep in mind that homes in sunnier regions will generally need fewer solar panels.

How Many Solar Panels Does An Rver Use And How Many Solar Panels Do You Need On A Boat

Though these percentage ranges are relatively accurate, they are still not pinpoint precise. They are not precise enough for those who wish to calculate their requirements as accurately as possible at least without there being any waste in the process.

Understanding BatteriesThe Key to Specific RV and Outhouse Calculations

When using an RV or camper, it is the output of the battery that is really going to determine exactly how much solar power is required to meet your energy requirements.

This is the same if you are powering a workshop or shed too. You are ultimately going to have to generate enough power to be able to effectively recharge and sustain the battery that feeds power into your appliances from your solar panel array.

To make calculating as easy as possible for you, we have compiled a list of various different battery sizes and types in conjunction with the amount required to sustain them and also the number of panels that you will need in order to achieve these various wattage outputs too. Please note that every 100 usable battery hours require precisely 1,280 watts worth of power. Various battery types and their power requirements are as follows.

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Solar Panel Installation Costs

After using the solar panel calculator and purchasing everything you need for your system, it may be possible to install your home solar panel kits on your own. To do so, youll not only need to be handy, but youll need to have experience with electricity and the ability to safely and securely climb onto your roof.

The majority of people will need to hire professionals, which will add to their solar panel installation costs. In general, solar installers will charge somewhere between $0.75 and $1.25 per watt for their labor. This cost is another reason why its helpful to use a solar cost calculator to know how many watts you plan to install.

Factoring in the installation costs will also help you to determine your payback period, which is usually around eight years for most systems in the United States.

What Is Your Target Daily Average

The thing with solar panels is that they will not work at full efficiency all the time. It could be a cloudy day they could have some unexpected shade there are a number of reasons as to why this could happen. As a result, experts recommend that you leave a cushion of 25% when it comes to calculating how much energy you will use on a daily basis. This allows you to offset any inefficiencies that may occur.

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Number Of Residents And Amount Of Energy You Use

Households with more members normally use a higher amount of electricity, and this also means they need more solar panels to increase energy production.

Electricity usage is a very important factor, as it determines how much power must be generated by your solar panel system. If your home uses 12,000 kilowatt-hours per year and you want to go 100% solar, your system must be capable of generating that amount of power.

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Determine Your Homes Electricity Needs

According to the latest data from the U.S. Energy Information Administration , the average American home uses 10,649 kWh of energy per year. However, this varies depending on the state. For example:

• Louisiana homes have the highest average consumption, at 14,787 kWh per year.
• Hawaii homes have the lowest average consumption, at 6,298 kWh per year.

To more closely estimate how much energy you use annually, add up the kWh reported on your last 12 monthly electric bills. These numbers will fluctuate based on factors like the size of your home, the number of residents, your electricity consumption habits and the energy efficiency rating of your home devices.

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Is A 4kw Solar System Worth It

With the average U.S. irradiance of 5.3kWh/m2/day , a 4kW solar system generates about 21.2kWh of energy per day, or 7738kWh/year.

This is quite a lot less than the average energy consumption for a U.S. home is 11000kWh/year. A 4Kw solar system may or may not meet a homes energy requirement, as calculating solar depends on the location and how much the home uses.

Whether such a system is worth it or not also depends on the electricity cost, which varies from state to state. The cost of the solar system must also be known, and this asset cost may be reduced by government or state solar incentives.

How Many Solar Panels Power A House Key Takeaways

• An average home needs between 20 and 24 solar panels to fully offset utility bills with solar.
• The number of solar panels you need depends on a few key factors, including geographic location and individual panel specifications.
• Youll need more solar panels for the same output if you live in Massachusetts compared to California.
• Compare free, custom solar quotes on the EnergySage Marketplace.

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Size Of Your Home And Available Roof Space

Larger homes tend to consume more electricity, and they generally need more solar panels. However, they also have the extra roof space necessary for larger solar panel installations.

There may be exceptions to this rule for example, a 2,000-square-foot home with new Energy Star appliances may consume less power than a 1,200-square-foot home with older, less-efficient devices. When it comes to installation, solar panels can be placed on many types of surfaces.

However, your roof conditions may limit the number of solar panels your home can handle. For example, if you have a chimney, rooftop air conditioning unit or skylight, youll have to place panels around these fixtures. Similarly, roof areas that are covered by shadows are not suitable for panels.

Also, most top solar companies will not work on asbestos roofs due to the potential health risks for installers.

Summary: How Many Panels Do You Need

Knowing the answers to the above questions will give you an idea of the ideal number of panels for your electricity generation needs or at least a realistic range. Next, a professional installer needs to assess your roof architecture, angle to the sun and other factors to see if and how youd be able to physically arrange the right number of panels on your roof to achieve your daily energy production goals.

You should also consider net metering as youre considering how much money youll save and make from your solar system. Net metering is how your utility company credits you for producing excess solar energy when the sun is shining and then lets you draw from those credits when youre using conventional power grid at night, if you dont store your excess solar energy in a battery storage system.

To get started, check out our solar calculator, which can help you figure out how much you might save going solar.

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Solar Panel Specific Yield

After you determine how many kWh of electricity your home uses annually, youll want to figure out how many kWh are produced by each of your solar panels during a year. This will depend on the specific type of solar panel, roof conditions and local peak sunlight hours.

In the solar power industry, a common metric used to estimate system capacity is specific yield or specific production. This can be defined as the annual kWh of energy produced for each kilowatt of solar capacity installed. Specific yield has much to do with the amount of sunlight available in your location.

You can get a better idea of the specific yield that can be achieved in your location by checking reliable sources like the World Bank solar maps or the solar radiation database from the National Renewable Energy Laboratory.

To estimate how many kW are needed to run a house, you can divide your annual kWh consumption by the specific yield per kilowatt of solar capacity. For example, if your home needs 15,000 kWh of energy per year, and solar panels have a specific yield of 1,500 kWh/kWp in your location, you will need a system size of around 10 kilowatts.

Paradise Energy Solutions has also come up with a general formula to roughly ballpark the solar panel system size you need. You can simply divide your annual kWh by 1,200 and you will get the kilowatts of solar capacity needed. So, if the energy consumption reported on your last 12 power bills adds up to 24,000 kWh, youll need a 20 kW system .

How Can I Plan For My Future Energy Needs

They say history repeats itself, but in electrical usage terms that is not always the case. A panel count based on your history will only be helpful if you continue to live your life the same way you are living now.

At Sugar Hollow Solar, in our proposal process we always make a point to ask homeowners if they have any big life changes coming up in the future that will impact their energy usage. There are lots of ways that your usage can change:

• Are you planning on purchasing an electric vehicle that youll need to charge at home?

• Is the size of your family changing one day soon?

• If you are on the verge of having a new baby or having a child go off to college, your energy usage is about to change quite a bit. Those changes will alter the calculation for how many solar panels your home will need.

The major takeaway here is that your history is only the first place to start estimating your power needs. Youll need to consider your future energy needs as well.

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How Many Solar Panels Do I Need Step

Now that you know what factors you need to consider when designing your solar panel system lets go through an example that will help you better understand how to implement these factors into your planning.

It is important to note, however, that the values used in this example are an average for the entire United States. Therefore, when calculating the number of solar panels for your property, be sure to use values of your own state and property.

The Physical Size Of The Solar Panels Youre Using

It is clear that the size of your roof plays a decisive role in determining the number of solar panels you can install. But did you know that your roof space can also play a part in deciding which type of solar panels you can use?

The size and quantity of solar panels are crucial factors if you have a tiny or irregularly shaped roof. With an expansive usable roof area, you have the option to purchase a large number of big, low-efficiency panels in order to save some cost, all the while meeting your target energy output. However, if your usable roof space is tight or partially unusable, using fewer high-efficiency panels that are small in size might be your only viable option for generating enough power to meet your homes energy requirements.

Solar panels for residential properties usually measure in at 5.4 feet by 3.25 feet or 65 inches by 39 inches, with some variation across manufacturers. For ages, these measurements have remained mostly the same, yet the efficiency and power output of that same footprint has improved substantially.

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