At more than 109 times wider than Earth, the sun is the fiery focal point of our solar system. Amazingly, this vast ball of energy can charge a multitude of electronic gadgets that we carry around, from watches and cell phone chargers to flashlights and speakers. The sun also powers the satellites and space stations that orbit our world.
In 2022, around 3.4% of all United States electricity generation came from solar panels. That’s just the start; almost half of all extra national electricity will be generated by newly-added solar panels.
The solar revolution is also coming to people’s homes. Today, almost 4% of homeowners have some form of solar panel system powering their property. Let’s look at how homeowners can drive a green energy revolution with solar panels while saving money on their energy bills. But to do that, we must answer the question: How much energy do solar panels produce?
Who Discovered How to Capture Solar Energy?
It was way back in 1839 that French physicist Edmond Becquerel discovered that certain materials produced small amounts of electric current under light exposure. Becquerel went on to define what became known as the photovoltaic effect, where photovoltaic (PV) cells turn sunlight directly into electricity.
New York inventor Charles Fritts made the first solar cell in 1883 by painting the chemical element selenium with a thin layer of gold. Its conversion rate was a weak 1-2%.
Several attempts to improve solar cell efficiency followed. Then, in 1954, the PV technology of modern solar panels appeared thanks to the silicon PV cell developed at Bell Labs, which converted enough energy from the sun to power electrical equipment.
How Do Solar Panels Produce Energy?
Solar panels use kinetic energy, the energy of movement, to create electricity.
Each panel has thousands of photovoltaic cells, the cells that convert sunlight to electricity. The magic happens between two layers of silicon within these cells — one is altered to have a positive charge, the other a negative charge.
At an atomic level, sunlight’s photons hit the cells and force an electron from the negative charge to the positive one. This action releases a tiny amount of electrical energy. The positive electron eventually returns to the negative charge, creating a constant electrical current.
These electrons switch — movement — from negative to positive charge many millions of times a second. These actions create a direct electrical current, something only possible when sunlight’s photons cause this reaction within a solar PV panel.
How Does a Home Solar Energy System Work?
Solar panels work by converting sunlight into a direct current (DC). However, our homes and appliances need alternating current (AC).
Direct current electricity from solar panels feeds into a solar inverter within the home which converts the DC into a usable AC. A household’s appliances can draw power from this renewable energy source rather than the power grid.
Sometimes solar panels produce excess energy, or no one is home to use their power output. Battery storage means this extra energy can be stored in a battery for later use. Batteries mean the clean energy solar panels produce in a more flexible and valuable way.
Alternatively, some electric companies offer incentives like discounts on electric bills for households that feed excess electricity back into the grid.
Learn more about Amigo Energy’s Solar Smart Credit plan.
How Much Power Does a Solar Panel Produce?
The amount of power a solar panel produces depends on many factors. These include solar panel efficiency, the amount of sunlight or hours of direct sunlight, the solar panel’s power rating, season, and weather conditions.
Before investigating those variables, talking about how much power a solar panel generates requires a quick review of some basic terms:
- Watts (W): The measurement of power
- Kilowatt (kW): 1,000 watts
- Kilowatt-hours (kWh): A measurement of electrical power over time — in this case, 1,000 watts over one hour
On a national scale, in 2021, the average American homeowner used 886 kWh of electricity every month, or 10,632 kWh annually. That compares to the average Texas household’s usage of 1,094 kWh monthly, or 13,128 kWh annually. How does that play out in the home?
An example of using electricity could be a cordless electric kettle which requires 1,500W to function. Boil that kettle continuously for an hour, and it would use 1,500W of power or 1.5 kWh of electricity.
Solar panels use the same kilowatt and watt measurements, but we’re talking about power production rather than usage. Let’s start by looking at an individual panel.
What Is Solar Panel Output?
Solar panel output means how much direct current one panel will produce during optimum conditions.
Most residential solar panels have an output of 250 to 400 watts. Assuming standard test conditions, higher-watt panels generate more electricity than lower-wattage panels. These output ratings are vital when thinking about installing a solar energy system.
Suppose you install one solar panel whose best wattage-hours performance is 400W or 0.4 kWh of electricity every hour. That solar panel wattage won’t be enough to boil the 1,500W kettle.
How Many Solar Panels Does My Home Need?
Calculating solar panel output requires a simple calculation: hours of direct sunlight x solar panel wattage.
Let’s assume six hours of direct sunlight for our 400W solar panel: six hours x 400W = 2,400 watt-hours, around 2.4 kilowatt-hours daily, or 850-900 kilowatt-hours annually for one panel.
The average U.S. home needs 10,632 kWh of electricity each year, or 29 kWh daily, meaning 12-13 panels of 400W, assuming six sun hours daily and optimum operating conditions. In the more power-hungry Texas households, that’s more like 15-16 panels of 400W.
A home may well need more than our estimate because of solar panel sizes. Most residential solar panels contain 60 or 72 cells. The 60-cell panels are smaller (3.25ft by 5.25 ft) and have lower wattage and won’t be 400W. Conversely, 72-cell panels are a foot larger (3.25ft x 6.42ft), heavier, and not always suitable for homes, but could reach our example 400W.
The reality is that an average American home needs more solar panels than our example. A 60-cell solar panel usually has around 320W output, so the average U.S. household needs a 6.5 kW system to cover its total electricity usage. In Texas, that grows to about 26-27 panels to cover the average annual amount of electricity consumed.
What’s the Most Efficient Solar Panel?
Solar panel installation is not just about calculations; efficiency ratings are also vital.
Solar panels bring significant upfront costs, and there are two primary types available: monocrystalline and polycrystalline.
Monocrystalline solar panels have a much higher efficiency rate (16-23%) for converting sunlight into electricity than polycrystalline panels (15-19%).
Perhaps unsurprisingly, the high efficiency of the monocrystalline panels is reflected in the panel manufacturer’s prices. Monocrystalline panels are typically pricier than polycrystalline but also last longer, have a more attractive black finish, and remain more efficient at harnessing the sun’s powers over the years. Like most purchases, the best solar panels come with a higher price.
How Much Does It Cost to Install Solar Panels in My Home?
In 2023, a 6 kW system in the United States costs between $16,870 and $23,170 to install after applying for the 30% federal solar tax credit. There may be further state and federal programs to help with installation costs, so be sure to explore your options.
On average, it takes around eight years to recoup your return on investment for a home solar energy system. After that, the free electricity available — plus any bill credits from an electric company — will help reduce electric bills further. Moreover, most panels add value to a home, which can help if you decide to sell your place.
Political will is also pushing solar. California requires solar panels to be installed on all new homes. Thanks to solar energy, policymakers think homeowners might save $19,000 over 30 years. Another option is leasing solar panels.
How Much Power Will My Solar Panels Generate?
Many variables affect how much electricity your solar panels will produce. Always consult professional, qualified solar panel installers and manufacturers before fitting a solar panel array.
Professionals will ensure your solar panels face the right way, at the right angle, and in the optimum area to capture the sun’s power. They’ll also install a system appropriate to your household’s energy needs.
Remember, the amount of energy your solar panels produce doesn’t just depend on their size and efficiency. Here’s why.
What Affects the Efficiency and Output of Solar Panels?
How much energy comes from a PV panel? We’ve calculated their solar output in optimum conditions. However, the following factors are also essential to guarantee your solar panels bring maximum energy benefits.
First, the panel’s size and composition — e.g., monocrystalline or polycrystalline — dictate its potential.
Next, the local climate is an important factor. Overall, sunshine-drenched Texas and California receive plenty of sunshine hours and clear days every year; cloudy Vermont, less so. Solar panels work without direct sunshine and in winter, but the total number of modules needed in each region differs.
For example, every area has different energy demands; Texans may love to see solar panels powering their air conditioning during summer. But a Newport resident in Northern Vermont may struggle to power their electric-only home in the depths of winter.
Your home’s size, orientation, and the roof’s ability to support panels are crucial. Installers will look for south-facing tops (in the northern hemisphere) to maximize possible sunlight and tilt panels to capture the most light.
Keeping solar panels clean and clear of obstructions like dust, shadows from trees, or leaf debris maintain their efficiency.
How Much Sunlight Do My Solar Panels Require?
Solar panels usually require around four hours of sunlight every day.
How Can I Calculate Savings from Solar Panels?
First, you need to know your electric bill amounts. In 2021, in Texas, the average monthly residential electricity bill was $132.40, which is about $4.50 per day. A home used 36 kWh of electricity daily, at 12.11 cents per kWh.
A day with five sun hours and a home with a 6 kW system will produce 30 kWh that day, six kWh short of the average overall use. A homeowner would be charged for that six kWh used, so 73 cents instead of the usual $4.50.
Of course, it’s easier to look at monthly figures, where savings come in at around $110, assuming the same climatic conditions. Readings would change daily, but the example shows how effective solar panels can be in reducing electric bills.
Adding battery storage for nighttime energy use or feeding excess energy back into the power grid in return for electric bill credits are other ways to help reduce your energy bills.
Will Solar Panels Lower My Energy Bills?
Assuming your energy usage remains constant, the solar panels are correctly installed, and the weather is as expected, installing solar panels will lower energy bills.
Can I Power My Entire Home with Solar Panels?
Yes, people do power entire homes with solar panels, including hot water with solar water heater systems. However, solar panels don’t work at night, so you’d need a battery storage system to provide power in the evenings.
Many homeowners remain connected to the power grid in case their solar power system cannot meet spikes in demand. Heavy power drainers include running air conditioning, an oven, and charging an electric car simultaneously.
How Much Energy Do Solar Panels Produce? The Answer Depends on You
Solar panels are a rather effortless way to create renewable energy. Light forces electrons to move around within a photovoltaic cell, releasing electric power that forms a direct current. This current passes through an inverter to become an alternating current we use at home.
Modern versions of solar panels have initial upfront costs but that can be offset by tax credits and saving on electric bills. Professionally installed solar energy systems help reduce electric bills by allowing homeowners to use the energy they create on their rooftops.
The exact energy boost depends on the size, location, and type of solar panel installed. Weather, correct maintenance and cleaning, and energy usage also influence their efficiency.
How much energy do solar panels produce? The overarching answer is that it’s not a tremendous amount at present. But homeowners and states are joining the solar revolution as the industry continues to boom and more people make the switch to clean energy.
Brought to you by amigoenergy
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