How Does Solar Power Work on a House? Your Questions Answered
How does solar power work? A simple explanation is that solar panels convert sunlight into electricity that can be used immediately or stored in batteries.
The sun essentially provides an endless supply of energy. In fact, with the amount of sunlight that hits the earth in 90 minutes, we could supply the entire world with electricity for a year — all we have to do is catch it!
That’s where solar panels come in.
How solar panels power a home
Solar power has many applications, from powering calculators to cars to entire communities. It even powers space stations like the Webb Space Telescope.
But most people are concerned about how solar panels can power their house and reduce their electricity bill.
Here’s a step-by-step overview of how home solar power works:
- When sunlight hits a solar panel, an electric charge is created through the photovoltaic effect or PV effect (more on that below)
- The solar panel feeds this electric charge into inverters, which change it from direct current (DC) into alternate current (AC) electricity
- The AC electricity runs through your electrical panel and is distributed throughout your home — just like grid energy
- Excess solar energy is stored in batteries or pushed onto the grid to power local systems (like your neighbor’s house!)
- Through net metering, solar owners get credit for the excess energy they put on the grid to offset the grid energy they pull off the grid when their panels aren’t producing
- With battery storage, solar owners can store excess production to power their homes at night
Now that we’ve covered the basics, let’s break down how solar panels work in more detail.
How does solar power work? The photovoltaic effect explained
Solar panels turn sunlight into elctricity through the photovoltaic (PV) effect, which is why they’re often referred to as PV panels.
The photovoltaic effect occurs when photons from the sun’s rays hit the semiconductive material (typically silicon) in the cell of the solar module. The photons activate electrons, causing them to free themselves from the semiconductive material.
Photons hit the solar panel causing electrons to be freed during the photovoltaic effect.
The free electrons flow through the solar cells, down wires along the edge of the panel, and into a junction box as direct current (DC).
This current travels from the solar panel to an inverter, where it is changed into alternative current (AC) that can be used to power homes and buildings.
How is solar energy used to power your home?
Most home solar systems are “grid-tied” meaning that the solar system, home electrical system, and local utility grid are all interconnected, typically through the main electrical service panel.
Connecting these systems means you can power your home with solar electricity during the day and grid electricity at night. It also means your solar system can push excess electricity onto the local grid to power surrounding systems, like your neighbor’s house.
Through net metering, you earn credit for excess solar production that can be used to offset the grid electricity you use at night.
Home solar with battery storage
Home solar with battery storage works similarly to the process above, but intsead of pushing excess solar production onto the grid, it’s first stored in batteries in your home or garage.
Pairing solar and battery is especially handy for:
- Off-grid solar systems
- Backup electricity during power outages
- Areas without net metering policies
- Powering your home on 100% clean and renewable energy
What types of material are used in solar panels?
The most common residential solar panels contain monocrystalline or polycrystalline (also called multicrystalline) solar cells.
Both types of cells produce electricity when exposed to sunlight, however there are some key differences between the two:
| Monocrystalline solar cells | Polycristalline solar cells |
| Tend to appear darker in color, often black or dark grey | Often appear a dark blue when exposed to light |
| Performs better in high temperatures and shady conditions | Less efficient at higher temperatures |
| Tend to be more expensive | Tend to be less expensive |
If space is limited on your roof or project site, a higher-efficiency, monocrystalline panel may be preferred, and could result in a better return on investment. Alternatively, a lower-cost, slightly less efficient, polycrystalline panel may do the job just as well if you have ample roof space on your home.
Many panel manufacturers also build panels containing both mono and polycrystalline wafers to form solar cells, capable of harvesting energy from a wider spectrum of light.
Be sure to ask what type of cell (“mono or poly”) your home solar system design contains, This distinction may affect the aesthetics and economics of your project.
How does sun exposure affect solar panel efficiency?
It is important that your solar panels receive good insolation (sun exposure) throughout the day and are free from as much shading from trees or neighboring obstructions as possible.
There are a number of factors that influence solar panel efficiency. They include:
- Temperature — Solar panels operate best in temperatures between 59 and 95 degrees Fahrenheit
- Type of solar panel — Solar panels typically range from 15-20% efficient, with the best panels pushing 23%.
- Shading — Solar panels perform best in wide-open sun. Even partial shading can substantially reduce the efficiency of a panel
- Orientation and angle — Solar panels perform best when they are directly facing the sun and are often tilted to increase efficiency
Solar engineers use satellite imagery to determine which panels and placement will provide optimum solar panel efficiency for you home.
How does solar power work FAQs
How does home solar power work?
Solar power works by converting sunlight into electricity through the photovoltaic (PV) effect. The PV effect is when photons from the sun’s rays knock electrons from their atomic orbit and channel them into an electrical current.
Using PV solar panels, sunlight can be used to power everything from calculators to homes to space stations.
How does solar power work at night?
Solar panels require sunlight to generate electricity, so they do not generate electricity during the day.
However, home solar systems typically generate excess electricity during the day, which can be stored in batteries or sent to the local grid in exchange for net metering credits. This is how solar owners maintain power when the sun isn’t shining.
Do solar panels work on cloudy days?
Yes, solar panels still generate electricity on cloudy days, although not as effectively as sunny days. Solar panels can capture both direct and indirect light (light that shines through clouds), but perform at around 10-25% of their normal efficiency when it’s cloudy.
Cloudy days can be beneficial, however, as rain washes the panels and increases their overall efficiency.
What Are Solar Panels Made Of?
You might know what solar panels can do – convert sunlight into energy, save money, create energy independence, increase your home’s resale value – but.
Do Solar Panels Work At Night?
Do solar panels work at night? The short answer is: no, solar energy systems only operate during the day. This is because the power from.
How Much Energy Does a Solar Panel Produce?
One of the most important features of a solar panel is how much energy it can produce. After all, that’s what they’re designed to do.
Bacteria-enhanced Solar Can Boost Production in Cloudy Skies
In May 2018, researchers at the University of British Columbia discovered a new way to build solar cells that incorporate bacteria. Yes, germs… But.
Does Solar Panel Temperature Coefficient Matter?
If you are trying to maximize the amount of energy that your solar panel system can generate, then your solar panel’s temperature coefficient is.
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How are solar panels manufactured?
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Monocrystalline Solar Panels vs Polycrystalline Solar Panels
Over six decades ago, New Jersey scientists announced their invention of a practical silicon solar panel. Solar panels have come a long way since then.
How Do Solar Panels Produce Electricity?
Solar panels contain cells of semiconductive material, usually, silicon usually encased in a metallic frame and tempered glass. When subject to sunlight, photovoltaic cells create.
Why Falling Back is Bad for Solar
With daylight savings recently ending, it is that time of year again to reflect on why “falling back” is a really bad idea. In the.
Off-Grid Home Solar Power Systems
Are you a homeowner looking to power your home without relying on the grid?
A custom off-grid solar system is an excellent option for those who want to make their mid- to large-size homes self-sufficient. Without relying on the grid, you must generate enough energy through your own renewable sources to power your home; this is accomplished by storing energy in a battery bank that’s charged with electricity from solar panels.
We offer kits which include all the components required to ensure you get the correct amount of power. day and night! Unsure how to install it? Get in touch with us today and one of our experts will guide you through the process of constructing a perfect off-grid home system tailored for your unique needs.
Contact us now at 877-878-4060 or submit an online quote request and get started powering your home with an off-grid solar system today!
If you are looking for a smaller off grid system check out our off grid cabin and tiny house solar power systems. If you are looking to use the utility grid sometimes, check out our battery backup solar power systems and energy storage systems.
| Price | |
| 9,193.88 | |
| 10,051.20 | |
| 16,122.95 | |
| 1,294.16 | |
| 6,584.48 | |
| 779.90 | |
| 3,106.99 | |
| 2,274.15 | |
| 6,615.22 | |
| 816.20 | |
| 4,633.69 | |
| 3,383.17 | |
| 13,312.34 | |
| 1,477.13 | |
| 10,387.31 |
Power Your Home Without The Grid!
Homeowners, looking for an efficient way to power your home?
Going off-grid with a solar system may be the perfect solution for you! Solar systems are an environmentally friendly, cost effective way of providing your own energy source. Plus, taking the time to size your system properly ensures you get the maximum efficiency and power out of it initially and in the future.
With no grid limitations and lack of ongoing fees or connections, going off-grid with solar power is a great option for homeowners who want their own independent energy source. It will provide sustainable energy for years to come!
Keep reading to find out more about choosing an off-grid solar system that’s right for you! Find a per-designed kit that meets you needs or contact us for a custom off grid quote.
Get a Little Help from the altE Calculators
Off-grid living is appealing for many reasons. Maybe your utility company is unreliable, or power from the utility company in your area is too expensive. Regardless of your reason for going off-grid, the first step is to determine how much power you will need to produce and store. altE’s off grid solar calculator and loads list calculator will help you figure out these figures.
Taking the time and effort to evaluate your power needs ensures you are installing a solar system that meets your needs now and into the future. As you size a system to meet your needs you will probably find ways to use less power, whether it’s replacing old lighting or appliances. Going off-grid requires maximum efficiency, and identifying ways to become more efficient and reduce waste will make sure you always have the power you need.
In this next video we walk you through altE Store’s off-grid solar calculator. The altE off-grid calculator is a great place to start planning your system. The calculator covers everything from the number of solar panels needed, to the number of days of autonomy required for your needs.
Check out our video that outlines the 6 steps required to design a DIY off-grid solar system. We cover everything you need for a DIY solar powered system.
How to Choose the Best Off-Grid Solar System for Your Home
Are you considering installing an off grid solar system in your home? With the rising cost of electricity, an off grid solar system can be a great way to lower your energy bills and reduce your dependence on the utility grid. But how do you choose the best off grid solar system for your home? We’ll explore the key factors to consider when selecting an off grid solar system for your home, so you can make the best decision for your needs.
Determine Your Power Needs
Before selecting an off-grid solar system, you’ll need to determine your power needs. To do this, you’ll have to consider how much electrical energy you use on a daily basis and what type of solar batteries you plan to use for energy storage. Your solar battery should be sized to match the daily load and provide enough capacity for any anticipated future power needs. When considering battery capacity, be sure to factor in the amount of energy needed for lights, appliances, electronics, heating and cooling.
When determining your power needs, it’s also important to consider the type of solar batteries you will use. Lead-acid batteries are a common type of solar battery used in off-grid power systems, although there are newer, more efficient lithium-ion batteries now available as well. Lead-acid batteries are typically inexpensive, but require regular maintenance and replacement and have a shorter life span than lithium-ion batteries.
In addition to assessing your current power needs, you should also consider any backup power sources or grid power you may need in the event of a blackout. Stand-alone power systems are designed to provide source of electricity in the absence of grid power, so it’s important to choose a system that can support your expected energy needs in the event of an emergency.
Choosing the right off-grid solar system is a major decision, and determining your power needs is an essential first step. With careful planning and consideration of your energy requirements and carbon footprint, you can select a system that will help reduce your reliance on the electrical grid and create a more sustainable home.
Read more about the Components of an off-grid solar power system in our Resource Library.
Find the Right Solar Panel
When it comes to choosing the right solar panel for your off-grid home solar power system, there are several factors to consider. You need to consider the battery capacity, the type of batteries you will be using (such as lead-acid or deep cycle), and your estimated carbon footprint.
The size of the solar panel will depend on the battery capacity of your solar battery storage system. Your batteries need to store enough electrical energy to power your off-grid system and provide backup power in case of outages.
Finally, you should consider the impact that your off-grid power system will have on the environment. An off-grid system eliminates the need for grid power, reducing your dependence on fossil fuels and your overall carbon footprint. With an off-grid system, you can also use renewable energy sources like solar and wind power, allowing you to reduce your environmental impact even further.
Choosing the right solar panel is an important part of building an off-grid home solar power system. Make sure to take into account your home’s power needs, the type of batteries you plan to use, and the environmental impact of your system before selecting the best solar panel for your needs.
Want to learn more about the different types of solar cells used to make solar panels? Read our Comprehensive Guide to the Different Types of Solar Cells then shop our curated price list of solar panels.
Choose the Right Battery
When selecting a battery for an off-grid home solar power system, it is important to choose the right type of battery that meets your needs. Solar batteries are deep cycle batteries that are designed to store energy and release it as electrical energy when needed.
Lead-acid batteries are most commonly used in off-grid power systems because they offer a high capacity and long battery life. However, there are other types of batteries available such as lithium-ion, which can be more efficient than lead-acid batteries.
When choosing a battery for your off-grid home solar power system, consider the battery’s capacity and its ability to provide backup power when the grid power is down. The battery capacity will determine how much electrical energy you can store in the battery storage system. It is also important to think about how often you will need to charge the battery, since this will affect its battery life.
When selecting a solar battery for your off-grid power system, it is important to consider its environmental impact. Using solar batteries to reduce your carbon footprint is an excellent way to help the environment and make your home greener. By using an off-grid power system instead of relying solely on the electrical grid, you can reduce your electricity costs while still having access to a reliable backup power source.
Read more about solar batteries and then shop our extensive listing of solar battery prices.
Consider an Inverter
When installing an off-grid home solar power system, you must consider an inverter. An inverter is a device that converts the direct current (DC) generated by your solar batteries into alternating current (AC) that can be used to power your home appliances. This is important since most electrical devices and appliances require AC power, not DC power.
Inverters come in many shapes and sizes, and you need to select one based on your energy needs. Generally speaking, a good quality inverter will have a longer lifespan than other components, such as your solar batteries or deep cycle battery. When selecting an inverter, make sure it is compatible with your solar batteries and other components of your off-grid power system.
An inverter also plays an important role in reducing your carbon footprint. It can help you save energy and money by providing a backup power source during times when the grid power is down or unreliable. Plus, if your battery storage systems are big enough, you may not even need to use grid power at all.
When selecting an inverter for your off-grid power system, consider its power efficiency and battery capacity. Inverters can vary in power efficiency and battery capacity, so make sure you choose one that fits your needs and lifestyle. You also want to pay attention to the quality of the inverter and its warranty period since this will affect its overall performance and battery life.
By carefully choosing the right inverter for your off-grid power system, you can ensure that it works efficiently and effectively for years to come. With the right components and an efficient inverter, you can enjoy reliable stand-alone power systems that reduce your carbon footprint and help you save money in the long run.
Identifying a solar charge controller
A solar charge controller is an essential component of any off-grid solar power system. It regulates the electrical power that is generated by the solar panels and sent to the battery. By regulating the flow of electricity, the solar charge controller prevents your battery from overcharging, which can reduce its lifespan. It also optimizes the energy efficiency of the system by ensuring that your battery gets the maximum amount of power from the solar panels.
When selecting a solar charge controller, you should consider its voltage compatibility with your system, as well as the amount of current it can handle. You should also make sure that the solar charge controller is compatible with your other components such as the solar panels and batteries. Additionally, some solar charge controllers come with built-in features like load control and temperature compensation, which can help you further optimize your system’s performance.
Balance of System parts
The Balance of System (BOS) parts refer to the components necessary for a successful off-grid power system, other than the solar panels and batteries. These parts include all the hardware, wiring, and components necessary to complete the electrical circuit from the solar panel to the battery and then to the point of use.
Take your off-grid living to the next level with solar power.
Get step-by-step guidance for wiring and installing your own home solar system with our DIY tutorial. Are you planning on installing your off-grid solar system yourself? That’s great! We’re here to help.
In the video below we walk you through wiring your solar system components together for a safe DIY solar installation. You will learn the basic components of an off-grid solar power system, with example schematics.
importantly, you’ll learn how to safely wire and interconnect everything from your DIY solar panels, to your charge controller, battery bank, inverter, and balance of system components.
For further reading, check out our post Everything You Need to Know About Going Off-Grid with Solar in our off grid Resource Library. Read more about off grid living in the altE blog. Both Motherearth News and Off the Grid News have further articles about an off grid solar system, and the National Renewable Energy Laboratory. has additional information.
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Rechargeable Solar Battery System For Your Home
Consult with your sales representative for battery availability and backup capabilities in your area. Available while supplies last.
Generate, store, and manage clean, affordable solar energy on your terms. With Sunrun Brightbox, your Brilliant Home™ comes full circle. Brightbox is more than just solar battery storage—it’s a holistic service that puts the power in your hands. We only partner with top-notch innovators in lithium-ion battery technology, so you’re backed by the highest quality products available. Brightbox is currently available to new Sunrun solar customers only.
Sunrun helps you go solar and finds the back-up options that best fit your needs.
Our solar-powered batteries are best-in-class. Choose to back up your whole home with Tesla Powerwall, or just the essentials with LG Chem.
Our customized plans give you the financial flexibility you need. Choose from multiple lease, financing, and cash options.
We’re with you every step of the way. From finding the right solar plan to monitoring your solar system, Sunrun safely sees you through your solar journey with our Solar Guarantee. Go solar virtually with no in-person contact.
Keep the lights on, protect your family and secure your home office during blackouts. Our 100-year-old utility grid is expensive, dirty, and susceptible to extreme weather. As blackouts become the new normal, Brightbox backs you up with reliable, clean energy for your home and family.
Brightbox can buffer you from increasing energy costs so that you have power when you need it most. While we can’t predict how much or how often utility electric rates will rise or when exactly the power will go out, we can always count on the sun rising each day. Take charge of your electric bill and get control of your energy needs now and in the future.
The benefits of solar-powered batteries go beyond your home. Brightbox’s solar battery service enables you to consume more of the clean energy your solar panels produce, so you rely less on dirty and damaging fossil fuels while you decrease your carbon footprint. A cleaner and safer future starts today, and you can help create it by building a smarter energy grid.
Reliable energy when you need it most.
Find solar battery availability, information, and Sunrun locations near you. If we’re not there already, we may be in your community soon. Sunrun is committed to growing solar locally.
What kind of solar batteries does Sunrun use?
Brightbox offers two lithium-ion solar battery storage options: Tesla Powerwall and LG Chem. Compared to lead acid batteries, solar batteries using lithium-ion technology are more efficient and have longer lifespans. This makes them one of the best energy storage options when going solar.
What’s the difference between Tesla Powerwall and LG Chem?
Tesla Powerwall can provide whole home backup while LG Chem backs up to four circuits. There are also differences in the software and app functionality.
Request a free quote to get connected with a Sunrun Solar Advisor and determine which back-up solution will best meet your energy needs.
Are there solar storage incentives available?
One of the best solar storage incentives is the Federal Solar Tax Credit. The Federal Solar Tax Credit will deduct 26% of the cost of your solar energy system from your federal taxes. Starting in 2021, the value of the tax credit will step down to 22%. After 2021, the tax credit for residential solar ends.
Another option is to finance Brightbox with a lease. We’ll pass down the savings to you in the form of a lower and more predictable electric bill.
Net metering, which credits any excess power your solar system generates back to your electric bill, is another great incentive for many people that go solar. However, several states have chosen to adopt Time-of-Use (TOU) rates, which complicate the way your net metering credits are calculated. Brightbox can buffer you from peak TOU rates so you may save even more on your electric bill.
Will my Brightbox battery allow me to go off grid?
Our rechargeable solar battery systems are designed to keep you on-grid during normal service times while still providing reliable backup when the sun isn’t shining or during the event of an outage. This is the most reliable and economical way to use your Brightbox system, and the one most strongly recommended by Sunrun’s service experts.
How much storage does my home need?
Just like solar-only systems, the size of your rechargeable solar battery system is determined by your unique energy needs and habits. Factors, such as the amount of electricity you use at home and the devices and appliances you want to back up, will play a key role as you select the right battery storage solution for you.
Do I need solar panels to use Brightbox?
Aside from very rare exceptions, Sunrun’s Brightbox service includes rooftop solar panels.
Where will my Brightbox battery be placed?
The installation of Brightbox is a relatively simple process. It’s about the size of a water heater, and the system is mounted on a wall—usually inside your garage or outside of your home.
Is my Brightbox battery an IoT (internet of things) device?
While Brightbox requires an Internet or cellular connection to monitor your energy storage and usage efficiently, it can still operate without it. If for some reason Brightbox happens to go offline, you can resume your usage tracking when your internet connection is back to normal.
Do I need to do any setup or maintenance to Brightbox?
Most residential batteries are installed and configured with baseline settings by your solar installer. Solar batteries last anywhere between 10 and 15 years, and manufacturers typically offer a 10-year warranty.
How does Brightbox work?
Brightbox allows you to store the electricity your solar energy system produces during the day and use it when you need it most—such as in the evening during time of use (TOU) peak pricing or when the electric grid fails due to an extreme weather event or physical damage to the equipment.
What is Brightbox?
Brightbox is a holistic solar battery storage service that offers you clean, safe, reliable, back-up power to have better control over your home energy use and cost.
What are the benefits of Brightbox?
Brightbox solar battery storage systems can help you save money on utility bills, protect your home from power outages, and reduce your carbon footprint by supporting the production of clean, renewable energy.
Determining how many solar panels can power a house doesn’t have to be complicated. From watts to kilowatts and more, these tips will help you figure out how many solar panels are required in a solar system for home use.
By Melissa Graham | Updated Jan 26, 2023 4:28 PM
We may earn revenue from the products available on this page and participate in affiliate programs.
Q: I’m interested in installing a solar panel system for my home, but I don’t know much about solar panels. How effective are they? How many solar panels power a house?
A: There are plenty of incentives and benefits for switching from a traditional utility system to a solar-powered one. There are rebates and tax credits, but also the knowledge that you’re helping improve the environment. If you’re wondering, “How many solar panels do I need?” a few essential elements will answer the question. The tips below will help walk you through calculating how many solar panels you need and what factors will affect that number. While calculating these numbers yourself can give you an idea of what kind of solar array you’ll need, know that a qualified solar panel installer will do all of these calculations for you if you proceed with installing solar panels.
You’ll need to know three things: your annual energy usage, the solar panel wattage, and the production ratio.
”How much solar do I need?” is an expected question from a homeowner new to solar systems. To figure out exactly how many panels are required to run a home, you will need to consider your annual energy usage, the solar panel wattage, and the production ratio. These three factors are essential when converting to a solar system. While this calculation will give you a ballpark estimate, consider that other factors will affect the actual number of panels, which will be touched on later.
If you’re looking to install a designated solar heating system—one where solar panels heat liquid or air and convert it into central heating for a home—you’ll also need an experienced HVAC installer who can convert your existing central heating system to a solar heating one.
Maybe it’s time to call in a solar energy pro. Get free, no-commitment estimates from experts near you.
Look at your utility bill to determine how many watts you use.
Energy usage is measured in kilowatt-hours (kWh). KWh does not mean the number of kilowatts you use in an hour, but rather the amount of energy you would use keeping a 1,000-watt appliance running for 1 hour. The number of appliances that use power and how often they’re running will affect the usage. Anything plugged into a wall will count toward your energy usage, and bigger appliances like refrigerators and dishwashers use more power than a phone charger. For example, a 50-inch LED television uses around 0.016 kWh per hour, whereas an electric dishwasher will use about 2 kWh per load.
As of 2019, the average American household uses 10,649 kWh of electricity per year, according to the U.S. Energy Information Administration. But the best way to determine how much power you’ll need is by looking at your utility bills from the past year. This will give you a solid idea of your real-life energy needs, especially as power usage fluctuates throughout the year. The amount of energy you use will dictate the size of the system you need.
While installing solar panels can often reduce or even completely offset your monthly electric bill, remember that electric rates and usage are volatile factors. If the price of electricity or the amount you use drastically changes, your savings could change as well. For example, central to southern California is considered a great place to install solar panels because of the frequent sun—but it also is a state that regularly sees higher electricity prices.
Once you know your home’s energy demands, it’s time to start looking at panels. Look at different panels and see what the wattages are. The solar panel wattage is also known as the power rating, and it’s a panel’s electrical output under ideal conditions. This is measured in watts (W). A panel will usually produce between 250 and 400 watts of power. For the equation later on, assume an average of 320 W per panel.
Use your annual energy consumption and solar panel rating to calculate the production ratio.
You can calculate the production ratio when you have the numbers for your annual energy usage and the solar panel wattage. The production ratio is a system’s estimated energy output over time (measured in kWh) compared to the actual system size (measured in W). To calculate the production ratio, divide the energy output by the system’s total wattage. In the U.S., production ratios tend to fall between 1.3 and 1.6.
Maybe it’s time to call in a solar energy pro. Get free, no-commitment estimates from experts near you.
Once you have these three numbers, it’s time to calculate the number of panels. The formula is:
Number of panels = system size / production ratio / panel wattage
For example, using 10,649 kWh (the average energy usage of an American household), 1.3 (the low end of common production ratios), and 320 W (the average wattage of a solar panel):
Number of panels = 10,649 kWh / 1.3 / 320 W = 25.6
From this calculation, you can estimate that a house with these power requirements would need about 25 panels that produce 320 W.
Take the amount of sun your home receives into consideration.
Remember that this calculation assumes that the panels are running under optimum conditions. direct sunlight means your home can convert more energy into electricity. In states like Arizona and New Mexico, which are known to produce more sunlight than states in the Northeast, homeowners will likely need fewer solar panels. Nevada, Utah, California, Texas, and Colorado are other locations that usually produce more sunlight. But even if you live in a region or state with long winters or one that’s outside of the Sun Belt, you may need to purchase more solar panels to effectively run the home.
The size, shape, and material of your roof will also affect the best placement of solar panels. The ideal roof has no shade coverage from trees and large amounts of space facing south, west, or east—these are the directions that receive the most sunlight throughout the day in the northern hemisphere. Roofs with steep pitches make installing solar panels more difficult and can mean that an installer may not be able to fit as many panels on the roof. The same goes for oddly shaped roofs.
The number of solar panels you need will also depend on if your home will be on-grid or off-grid.
Often the more popular option, on-grid solar panel systems are connected to the public utility grid. If there isn’t enough sun to provide full power, the house can pull energy from the traditional grid, so it doesn’t have to go without electricity. On the other hand, an off-grid system is not connected to the public grid and is more common in rural or remote locations.
Off-grid systems rely on batteries to store power to keep the house running at night or on cloudy days. Off-grid systems will likely need more panels to run the house and store up excess energy. On-grid or off-grid systems can affect the overall cost of your solar power system.
Figuring out how much solar battery capacity you need is a task unto itself. Not enough capacity and you’ll run out of power in the middle of the night, but too much and you’ll add unnecessary complexity and maintenance costs. The number of batteries you need will also depend on the type of battery you choose. Lead acid batteries are more cost-effective, but lithium-ion batteries have better capacity, efficiency, and lifespan.
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The type of solar panel will affect its efficiency.
There are three types of solar panels available: monocrystalline, polycrystalline, and thin film. Monocrystalline and polycrystalline panels are both composed of cells made out of silicon. The silicon pieces are assembled to form a rectangle and covered with a glass sheet. Monocrystalline solar cells are cut from a single silicon crystal, while polycrystalline cells are composed of fragments of silicon crystals. This difference in construction affects the efficiency and price. Monocrystalline panels are more efficient and perform better, but they’re also more expensive. Polycrystalline solar panel are more affordable, but you’ll compromise a bit on efficiency and performance.
There are also thin-film solar panels. Like the name suggests, the cells are thinner than monocrystalline or polycrystalline. However, the actual panel itself may not be significantly thinner than other styles of panels. Thin-film panels are more portable and flexible than either monocrystalline or polycrystalline, but they’re less efficient. Different panels will have different pros and cons depending on your home, geographic location, and more, and your solar installer will be able to give you advice on what’s best suited for you.
While this guide can give you general information about the number of panels, solar panel sizes, and types of systems you might consider, remember that a qualified solar power installer will be able to give you more information that’s specific to your home. Many variables play into how efficient solar systems are, and it can be difficult to take all of those into consideration when you’re not experienced.