solar panel generating electricity for a home

How do solar panels work? The science behind solar energy production

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As the cost of solar energy has plummeted in recent years alongside major improvements in technical efficiencies and manufacturing quality, many homeowners across the U.S. are starting to look at solar as a viable alternative energy solution. And as solar enters mainstream energy markets, the big question is, “how do solar panels work?” In this article, we’ll break down exactly how solar panels produce energy for your home and how pragmatic going solar really is.

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Key takeaways: how do solar panels work?

  • Solar cells are typically made from silicon, which is a semiconductor and can generate electricity
  • This process is known as the “photovoltaic effect”
  • See how solar panels can work for you with custom quotes on the EnergySage Marketplace

How do solar panels work? Step by step overview

Solar panels work by absorbing sunlight with photovoltaic cells, generating direct current (DC) energy and then converting it to usable alternating current (AC) energy with the help of inverter technology. AC energy then flows through the home’s electrical panel and is distributed accordingly. Here are the main steps for how solar panels work for your home:

  1. Photovoltaic cells absorb the sun’s energy and convert it to DC electricity
  2. The solar inverter converts DC electricity from your solar modules to AC electricity, which is used by most home appliances
  3. Electricity flows through your home, powering electronic devices
  4. Excess electricity produced by solar panels is fed to the electric grid

How do solar panels generate electricity?

A standard solar panel (also known as a solar module) consists of a layer of silicon cells, a metal frame, a glass casing, and various wiring to allow current to flow from the silicon cells. Silicon (atomic #14 on the periodic table) is a nonmetal with conductive properties that allow it to absorb and convert sunlight into electricity. When light interacts with a silicon cell, it causes electrons to be set into motion, which initiates a flow of electric current. This is known as the “photovoltaic effect,” and it describes the general functionality of solar panel technology.

The photovoltaic effect

The science of generating electricity with solar panels all comes down to the photovoltaic effect. First discovered in 1839 by Edmond Becquerel, the photovoltaic effect can be generally thought of as a characteristic of certain materials (known as semiconductors) that allows them to generate an electric current when exposed to sunlight.

The photovoltaic process works through the following simplified steps:

  1. The silicon photovoltaic solar cell absorbs solar radiation
  2. When the sun’s rays interact with the silicon cell, electrons begin to move, creating a flow of electric current
  3. Wires capture and feed this direct current (DC) electricity to a solar inverter to be converted to alternating current (AC) electricity

We’ve put together an infographic below to explain how solar panels work:

How do solar cells work?

infographic explaining how solar works with your property

How does grid connection work with solar panels?

Though electricity generation with solar panels may make sense to most people, there’s still a lot of general confusion about how the grid factors into the home solar process. Any home that is connected to the electrical grid will have something called a utility meter that your energy provider uses to measure and supply power to your home. When you install solar panels on your roof or on a ground mount on your property, they are eventually connected to your home’s utility meter. The production of your solar system can actually be accessed and measured by this meter.

Most homeowners in the U.S. have access to net metering, a major solar incentive that significantly improves the economics of solar. If you have net metering, you can send power to the grid when your solar system is overproducing (like during the day in sunny summer months) in exchange for credits on your electric bill. Then, during hours of low electricity production (such as nighttime or overcast days), you can use your credits to draw extra energy from the grid and meet your household electricity demand. In a sense, net metering offers a free storage solution to property owners who go solar, making solar an all-in-one energy solution.

Additional important parts to solar panels

Aside from their silicon solar cells, a typical solar module includes a glass casing that offers durability and protection for the silicon PV cells. Under the glass exterior, the panel has a layer for insulation and a protective back sheet, which protects against heat dissipation and humidity inside the panel. The insulation is important because increases in temperature will lead to a decrease in efficiency, resulting in a lower solar panel performance.

Solar panels have an anti-reflective coating that increases sunlight absorption and allows the silicon cells to receive maximum sunlight exposure. Silicon solar cells are generally manufactured in two cell formations: monocrystalline or polycrystalline. Monocrystalline cells are made up of a single silicon crystal, whereas polycrystalline cells are made up of fragments or shards of silicon. Mono formats provide more room for electrons to move around and thus offer a higher efficiency solar technology than polycrystalline, though they are typically more expensive.

How homeowners can guarantee major solar savings

For those starting to consider a solar panel array for their home, there are a number of factors to consider including financing, equipment, installer selection, and warranties. In addition to all of these topics is the question of how to make sure you can get a good deal and generate strong energy savings in the long run. For people new to the solar shopping process, we have some key points of advice that will guarantee you get the best deal on your solar module system.

Three tips for solar shoppers

  1. Homeowners who get multiple quotes save 10% or more

    As with any big ticket purchase, shopping for a solar panel installation takes a lot of research and consideration, including a thorough review of the companies in your area. A recent report by the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) recommended that consumers compare as many solar options as possible to avoid paying inflated prices offered by the large installers in the solar industry.To find the smaller contractors that typically offer lower prices, you’ll need to use an installer network like EnergySage. You can receive free quotes from vetted installers local to you when you register your property on our Solar Marketplace – homeowners who get 3 or more quotes can save thousands on their solar panel installation.

  2. The biggest installers typically don’t offer the best price

    The bigger isn’t always better mantra is one of the main reasons we strongly encourage homeowners to consider all of their solar options, not just the brands large enough to pay for the most advertising. A recent report by the U.S. government found that large installers are $2,000 to $5,000 more expensive than small solar companies. If you have offers from some of the big installers in solar, make sure you compare those bids with quotes from local installers to ensure you don’t overpay for solar.

  3. Comparing all your equipment options is just as important

    National-scale installers don’t just offer higher prices – they also tend to have fewer solar equipment options, which can have a significant impact on your system’s electricity production. By collecting a diverse array of solar bids, you can compare costs and savings based on the different equipment packages available to you. There are multiple variables to consider when seeking out the best solar panels on the market. While certain panels will have higher efficiency ratings than others, investing in top-of-the-line solar equipment doesn’t always result in higher savings. The only way to find the “sweet spot” for your property is to evaluate quotes with varying equipment and financing offers.

For any homeowner in the early stage of shopping for solar that would just like a ballpark estimate for an installation, try our Solar Calculator that offers upfront cost and long term savings estimates based on your location and roof type. For those looking to get quotes from local contractors today, check out our quote comparison platform.

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25 thoughts on “How do solar panels work? The science behind solar energy production

  1. AvatarAMANDA HOng

    I bought the house had a solar panels free and clear. electric bill came first month is 17$ which is we didnt use bc the house was empty for construction. Is that normal if I stay there for and pay like 50$/m or 80$/m? if so that is alot if we have Solar right? The solar panels have been there for 16 years. THnks

    1. AvatarKevin

      As a solar panel user, former installer, and home energy auditor, I may be able to offer some insight. Your utility company will probably charge you a monthly administrative fee for having access to electricity. In our state, this is true whether you have solar or not and it’s the same price, $15. So even if I don’t use any utility electricity, I have to pay $15 a month. Some utilities may charge solar home owners a higher monthly administrative fee. Now, just because you have solar, doesn’t mean you won’t have an electric bill. It depends on so many factors; size of the array, efficiency, array orientation, wattage produced per panel, shadowing, time of year, where you live, how much you use, how efficient your home is, etc. Most homes don’t have enough roof top for panels to cover their electricity use their entire year, but you can get close. The 30 panels on my roof completely cover my electricity cost 2-3 months a year. Solar is important but you also need to make your house the most efficient it can be by air-sealing it first and then adding insulation. Replacing your windows is typically the last thing you should do to save energy in your house unless you have single pane glass. If replacing windows, purchase those that are Energy Star rated. The air leaks in your ENTIRE home are what cost you money. An efficient home still has 4.5 -6.5 ACH (air changes per hour). Yes, the air in your home is being replaced 4.5 to 6.5 times per hour due to air pressure and thermal dynamics. One that hasn’t been air-sealed has 15 – 25 ACH! You keep paying to condition the air coming into your home and that’s why your utility bills are so high! You need to address the air leaks in your home to get the most out of your solar solution, but do both. You can even do solar first, but the real gains come when you fix the box you call your home. Get a full energy audit from an experienced auditor.


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