Average Solar Energy Per Year, Month and Day

Introduction – Average Solar Energy

Harnessing the power of the sun is a sustainable energy source, but do you know what is the average solar panel output per day, per month, and per year? We compiled this data for 50 cities, in each of the 50 states. In addition, we also report on the solar production by the sun.

solar production by month
Solar inputs is measured in “solar hours”

What Is The Average Solar Panel Output Per Day?

Solar panel effectiveness depends on external factors such as amount of sun every day, and internal factors such as the efficiency and quality of panels. For the latter, there are ways to improve solar panel efficiency which we urge our readers to look at.

Average Solar Radiation Per Day And Solar Panel Output Per Day – United States

MonthSolar radiation per daySolar panel output per day*20 Solar panel output per day 
January3.23 kWh/m²0.77 kWh15.49 kWh
February4.03 kWh/m²0.97 kWh19.36 kWh
March4.98 kWh/m²1.20 kWh23.92 kWh
April5.82 kWh/m²1.40 kWh27.95 kWh
May6.20 kWh/m²1.49 kWh29.78 kWh
June6.56 kWh/m²1.58 kWh31.51 kWh
July6.60 kWh/m²1.58 kWh31.68 kWh
August6.22 kWh/m²1.49 kWh29.87 kWh
September5.61 kWh/m²1.35 kWh26.95 kWh
October4.49 kWh/m²1.08 kWh21.53 kWh
November3.53 kWh/m²0.85 kWh16.97 kWh
December2.87 kWh/m²0.69 kWh13.79 kWh
We assume solar energy conversation is 15% efficient and a solar panel is standard 1.6 m²

What Is The Average Solar Panel Output Per Month?

We also estimated the numbers for the average solar radiation per month and the average solar panel output per month. This is simply the per day numbers weighted by the number of days in the month.

Average solar radiation per month and solar panel output per month – United States

MonthSolar radiation per monthSolar panel output per month*20 solar panel output per month
January100.02 kWh/m²24.00 kWh480.09 kWh
February112.92 kWh/m²27.10 kWh542.04 kWh
March154.46 kWh/m²37.07 kWh741.41 kWh
April174.70 kWh/m²41.93 kWh838.57 kWh
May192.35 kWh/m²46.16 kWh923.27 kWh
June196.92 kWh/m²47.26 kWh945.22 kWh
July204.58 kWh/m²49.10 kWh981.99 kWh
August192.91 kWh/m²46.30 kWh925.98 kWh
September168.41 kWh/m²40.42 kWh808.36 kWh
October139.07 kWh/m²33.38 kWh667.52 kWh
November106.04 kWh/m²25.45 kWh508.98 kWh
December89.04 kWh/m²21.37 kWh427.41 kWh
We assume solar energy conversation is 15% efficient and a solar panel is standard 1.6 m²

Methodology

In general, solar production is higher in the summer months when there is more daylight and solar panels can produce more electricity.

Solar production typically decreases in the winter months due to shorter days and less sunlight. However, solar production is still significant in the winter, especially in sunny climates.

To calculate the solar energy production we break it into two steps: solar radiation and solar panel output by panels. Solar radiation refers to the amount of incident energy from the sun. This energy needs to be converted into usable electricity, this is the solar panel output.

We used the NREL.gov app to find the average solar radiation energy per day in the United States. We averaged the data over 50 cities, one for each state.

To be representative, we picked the largest city. This yields energy production per day (in kWh/m²), which changes throughout the year according to the month. Each month is different due to the changing relative trajectory of the sun.

To get the monthly production, we simply multiplied by the number of days for each month. Finally to get the annual production, we added up all of the monthly values.

Where you live exactly will yield systematically different results if its not one of the cities we surveyed. The figures start low in the winter, rise in the spring, peak in summer, before falling again in the fall season.

Average Solar Radiation Per Year For The United States

The average solar radiation per year is 1831.42 kWh/m². There’s no need to go by month for the average solar production per year. The value is found by adding up the estimated production per month over all months.

Average Solar Production In 50 States

Click on any state below to get the state’s local average solar production over all 12 months and the amount of electricity expected from one or more solar panels. Each state receives a different amount of sunlight over the course of the year.

AlabamaHawaiiMassachusettsNew MexicoSouth Dakota
AlaskaIdahoMichiganNew YorkTennessee
ArizonaIllinoisMinnesotaNorth CarolinaTexas
ArkansasIndianaMississippiNorth DakotaUtah
CaliforniaIowaMissouriOhioVermont
ColoradoKansasMontanaOklahomaVirginia
ConnecticutKentuckyNebraskaOregonWashington
DelawareLouisianaNevadaPennsylvaniaWest Virginia
FloridaMaineNew HampshireRhode IslandWisconsin
GeorgiaMarylandNew JerseySouth CarolinaWyoming

Assumptions For Average Solar Panel Output Per Year

The average solar panel output per year is 439.54 kWh. There’s no need to go by month for the average solar production per year. The value is found by adding up the estimated production per month over all months.

Explanation For Our Calculations

Solar radiation per day – computed as units of “peak sun hours” added up for the whole day. Comprises incident energy from the sun as it hits any part of the surface of the Earth. The energy is measured by kWh – or kilowatt hours per meter squared. It means the amount of energy used up or emitted by a 1 kilowatt power drain or source over the square meter area.

Solar panel output per day – assuming a 15% efficiency and a single panel size of 1.6 m², this is the energy produced per square meter from a solar panel over a month.

20 solar panel output per day – assuming a 15% efficiency and a single panel size of 1.6 m², this is the energy produced from 20 solar panels in a day. This is an optimal scenario because true solar panels will suffer more losses due to imperfect azimuthal angle and tilt.

Solar radiation per month – computed as units of “peak sun hours” as above, except now its for the whole month by multiplying by number of days.

Solar panel output per month – assuming a 15% efficiency and a single panel size of 1.6 m², this is the energy produced per square meter from a solar panel over a month.

20 solar panel output per month – assuming a 15% efficiency and a single panel size of 1.6 m², this is the energy produced from 20 solar panels over a month. This is an optimal scenario because true solar panels will suffer more losses due to imperfect azimuthal angle and tilt.

Impact On Electricity Production

The energy produced from solar panels will depend on your specific location, like what city, what state. It will depend on the azimuthal orientation of your panel. This means the compass direction that your roofs are “facing”. It will also depend on the tilt of your roof. The more directly facing the sun, the greater the energy production.

In the US, which is in the northern hemisphere, the best direction to face is south. This maximizes capture of solar radiation. In the southern hemisphere, the best direction is facing north to maximize solar radiation capture.

Finally, it will depend on the efficiency of the panel which on average is 15%. After factoring in all these variables, you will find that you fall far short of the theoretical maximum! In theory, 3-4 panels have the surface area for 10,000 kWh of solar energy per year. In practice, you will need 20 panels because of losses due to every factor.

The most common size for a panel is 1.6m².

The Best Months For Solar Production

The best months for solar production are typically those with the most sunlight, which in the United States is typically from May to October. These are also the months when solar panel output is highest. Also, solar production is lower in the winter months due to shorter days and less sunlight, but it can still be significant in sunny climates.

Solar Production During Winter

Solar production during winter is still possible, especially in sunny climates. Even though solar production typically decreases in the winter months due to shorter days and less sunlight, solar panels will produce a significant amount of electricity in sunny regions.

Basics Of Solar Energy

Solar energy is the energy that is in sunlight. This solar radiation can be used to generate electricity, heat water or air, or produce solar fuels. Solar panel technology has advanced significantly in recent years, making solar energy a more viable option for powering homes and businesses. Photovoltaic cells are what make up solar panels, and they are responsible for converting sunlight into electrical energy.

Photovoltaic cells are made of semiconductor materials like silicon. When photons from the sun strike the solar panel, electrons are jarred away from their bonds with the atoms that make up the silicon. The solar panel produces an electric field that causes these electrons to flow through the solar panel to create an electric current. This current can then be used to power homes and businesses. They are usually mounted on roofs where they can get the most exposure to sunlight.

Solar energy is a renewable resource, which means that it can be used over and over again and will never run out. It is not only a renewable source of energy but it is also considered to be a clean form of energy because its use does not result in the production of any carbon.

The production of solar panels incurs an emissions cost. This cost is still an order of magnitude lower over the life time energy production compared to using the grid. Panels have a reasonably long lifespan and require very little maintenance, which makes them a somewhat cost-effective alternative for the generation of power.

Advantages Of Using Solar Energy

In comparison to other kinds of energy, solar power has numerous advantages. So long as there is sunlight, solar energy is a renewable resource, which means it will never run out. When solar energy is employed, it produces no hazardous pollutants, making it a clean energy source as well.

It is incredibly cost-effective to use solar panels because they have a long lifespan and require little to no maintenance. Solar electricity may be used to power homes, businesses, and even automobiles, making it adaptable. It is possible to create electricity, heat water or air, or make solar fuels using solar panels as a source of energy.

This advancement in solar panel technology has made solar electricity a feasible choice for households and businesses in recent years. In addition, solar electricity is adaptable and may be utilized to power homes, businesses, and even automobiles. For example, solar energy is environmentally friendly because it is made from the sun’s rays.

Downsides Of Solar Production

In solar production, there are a few disadvantages to consider as well. Solar panels are expensive to install, and the initial investment is a barrier for some people. Solar panel technology is constantly improving. Correspondingly, the costs of solar panels are dropping every year due to improvements in production.

Another downside is that it is intermittent, originating from the fact that the solar energy system only produces electricity when the sun is shining. This can be a problem in cloudy or winter months when solar production is reduced. Statistically, this is factored into the calculations by the concept of “peak solar hours”. Another way to say it is that the energy is measured in terms of the brightest sunlight. Even a cloudy day will generate a low amount of energy that is a measurable fraction of the brightest sunlight.

Anne Lauer
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AnnaLauerisawriter,gardener,andhomesteaderlivinginruralWisconsin.ShehaswrittenforMotherEarthNews,Grit,andHobbyFarmsmagazines.Annaiswriting a new bookabout growingyour food for free and an ultimate guide toproducingfood at little to no cost.Whenshesnotwritingorgardening,Annaenjoysspendingtimewithherhusbandandtwoyoungdaughters.