What to know about buying a house with solar panels
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David McMillin is a contributing writer for Bankrate and covers topics like credit cards, mortgages, banking, taxes and travel. David’s goal is to help readers figure out how to save more and stress less.
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If you’re looking for a new roof over your head, you might also be thinking about whether what’s actually on that roof can help the planet. According to the National Association of Realtors’ (NAR) “2022 REALTORS and Sustainability Report”, more than 50 percent of real estate professionals say their house-hunting clients are interested in sustainability. They’re finding plenty of options to match their needs, too: 77 percent of Realtors indicate that there are homes with solar panels available in their local markets.
Currently, solar energy produces over 4 percent of all electricity in the U.S., according to the Solar Energy Industries Association (SEIA). But that figure is going to increase with new legislation that just made it through Congress. According to estimates from the White House, approximately 7.5 million more households will be able to install solar panels on their roofs thanks to the tax incentives in the Inflation Reduction Act of 2022.
If you’re thinking about getting ahead of the curve and buying a house with solar panels, here’s what you need to know.
What are solar panels?
First, a quick primer: Solar panels (not to be confused with solar shingles or tiles) are devices that collect sunlight and convert it into energy, which can be used for electricity or stored in batteries for later use. As much of the world looks for renewable energy to help replace fossil fuel consumption, solar panels – also known as photovoltaic, or PV, systems – harness the natural, “clean” power of the sun in the sky and help negate the effects of driving gas-guzzling cars and relying on coal-fired power plants.
Interest in such environmental concerns is figuring more and more in residential real estate transactions. Half of agents and brokers in the NAR study indicate they helped a client buy or sell a property with green features during the past 12 months — a notable jump compared with 32 percent who did so in 2021. specifically, the presence of solar panels on a property roof bumps up its perceived value, one-third of Realtors say.
questions to ask before buying a home with solar panels
When surveying a solar-paneled home, be sure to ask these key questions.
Who owns them?
While you might assume that buying a home means buying every piece of it, that’s not always the case with solar panels. In some cases, there is a lease arrangement where the owner of the home pays the company that owns the panels. Justin Baca, SEIA vice president of markets and research, says that around 25 percent of homes have third-party-owned solar panels, meaning the owner of the home pays a company a fee to use them.
“Homebuyers should ask whether the solar system is owned outright by the seller or whether they would have to take over a lease,” Baca says. “If there is a lease, they should check the terms to make sure they understand the costs and any options to buy out the lease. Either way, solar panels on the home are a great feature.”
Who installed the solar panels?
Make sure you ask whether a licensed professional installed the solar panels. There are plenty of self-installation kits available for DIY homeowners who aren’t afraid to get on their roofs. However, if the homeowner (or any non-professional) installs them, these panels may not qualify for protection under a warranty if the equipment fails.
What’s the condition of the roof?
With any home purchase, you want to know what sort of shape the roof is in. With a roof that has solar panels, the condition becomes an even more critical factor. If the roof is in bad shape, the panels have to be taken off before the roof can be repaired or replaced, and then reinstalled. This can add to the complexity, cost and length of any re-do. So, “the most important questions to ask are about the condition of the roof and panels themselves,” Waheed Akhtar, broker and owner of RE/MAX Dream Homes in Sacramento, California, says.
What will the maintenance needs be?
Like everything else in your home, solar panels may need to be cleaned or serviced from time to time to ensure they’re in the best condition possible.
“If you own the system in a place that gets a decent amount of rain, you likely won’t have to think about it for years,” Baca says. “I haven’t done a thing to my five-year-old system [in Syracuse, New York], and it’s performing as new.
However, “in places with more dust and less rain, cleaning based on local conditions isn’t a bad idea but should be done by an installer or other professional qualified to be on a roof safely,” he notes.
If you don’t own the panels outright, Baca points out that you won’t have to worry about the maintenance responsibilities. “If you have a lease, you likely have a performance guarantee, which will lower your lease payments unless the system performs to a certain level,” he says. “That makes maintenance the leasing company’s responsibility.”
What’s their average output versus the home’s average usage?
The main reason you’re buying a home with solar panels is to cover most – if not all – of your home’s energy needs. So, you’ll need to research the home’s average usage and compare it with the typical solar output. You can ask the seller for figures from the past year, and you can also use the National Renewable Energy Laboratory’s calculator to get a sense of how much energy you can expect to produce based on the location and the type of system.
After you understand how much of your own energy needs will be satisfied by the solar panels’ output, you’ll want to know if you have options with any surplus energy that you don’t use. Net metering, which involves selling the energy you don’t use back to other customers who need it, can provide additional financial benefits for you. This varies based on where the home is located (SEIA offers a map of states with net metering rules in place as a starting point). Be sure to ask your real estate agent for assistance in understanding if net metering is available for you.
What is the production guarantee?
In addition to knowing whether you can benefit if your system produces more than you need, it’s important to have an understanding of what happens if it produces less. Most companies offer production guarantees, which will reimburse you a designated amount if the system fails to deliver. For example, you might be guaranteed 12,000 kilowatt-hours in a year. If the system only produces 9,500 kilowatt hours, the company may need to issue you a check. Look at the contract to determine what, if any, guarantees are offered.
than one-third (36 percent) of Realtors feel that having solar panels on a home increased its perceived property value, according to the NAR’s “2022 REALTORS and Sustainability Report.”
Collection: Solar Panels
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HOW TO FIND THE BEST SOLAR PANELS FOR HOMES
When shopping for home solar panels, you need to consider factors like size, type, efficiency, price and warranty. We break down what you need to know and look out for.
Looking for our favorite picks? Check out our list of top-rated residential solar panels.
Solar Panel Sizes
Solar panels for homes or businesses are available in different sizes.
The 66/108-cell solar panel is the newest, most popular size available today. These panels measure around 68” x 45” and weigh about 45 lbs.
60/120-cell solar panels are also common and are about 4 to 5” shorter than a 66/108-cell panel.
Both sizes are suitable for home solar systems. Most customers choose 66-cell panels for residential rooftop projects. Consider a larger panel if you’re installing a ground-mount system or if your rooftop’s configurations allow for bigger panels.
To choose the cell count for your solar panels, select the best cost-per-watt option that fits your roof or ground configurations.
Polycrystalline and Monocrystalline
Solar panels are composed of cells made of monocrystalline (mono) or polycrystalline (poly) silicon. Today, most solar panels are monocrystalline.
You can identify a mono solar panel by its dark, even coloring. Poly solar panels are textured and resemble a granite countertop.
Mono solar panels are popular due to higher efficiency; however, poly panels have lower per-watt prices. Mono solar panels also perform better in low-light conditions compared to poly solar panels.
Half-cut Solar Cells
Half-cut solar cells are one of the latest developments in solar technology. They’re traditional solar cells split in half by a laser cutter, designed to prevent energy loss and boost performance.
As electrical currents move through wires and cells, some energy is lost, known as a resistive loss. A half-cut cell reduces resistive loss, therefore improving solar panel output.
Half-cut solar cells are also more efficient in shade. Panels with half-cut cells require double the wiring, so a shaded cell with lower output is less likely to impact the panel’s overall production capabilities.
Solar Panel Efficiency
Solar panels work by converting the sun’s energy into power for your home.
The average range for solar panel efficiency is 17 to 20%. A solar panel with 19% efficiency, for instance, can convert 19% of the sun’s energy into electricity.
Solar panel wattage output ranges from 310 to 420 or more watts, with an average per watt price of 68 to 75 cents. The number of watts indicates how much power the solar panel produces.
If you have a 320W panel and receive 5 hours of sunlight per day, the panel would produce 1,600 watt-hours, or 1.6 kWh per day (320W x 5 hours). In one year, each panel would generate 550 to 600 kWh.
High wattage output doesn’t necessarily mean better quality or performance. Choose higher efficiency if you’re working with limited space and need fewer panels to get the job done. Otherwise, standard efficiency panels work just as well — at a lower cost.
Solar Panel Prices
Solar panel vary, as low as 200 to 600 or more per panel. depend on the type of panel (mono vs. poly), manufacturer, cell size and wattage output.
Because every home is different, the total number of solar panels needed for your residence will also vary. Remember to factor in the price of inverters, racking, other parts and equipment and installation costs.
At GoGreenSolar, we’ll work with you to determine a solar panel setup that fits your budget and energy needs. When you buy solar panels from us, you’ll also receive end-to-end installation support from our in-house team so you don’t have to spend thousands of dollars hiring a professional.
Solar Panel Warranties
Solar is a significant investment, so it’s crucial to understand how solar panel warranties work.
Product Warranty
A product warranty covers physical defects or faulty manufacturing. Most solar panel brands offer at least a 10-year product warranty, while some name brands provide 20 to 25 years.
Performance Warranty
A performance warranty guarantees that your solar panel will continue to produce close to its intended output throughout the warranty period. All panels, regardless of brand or wattage, decrease output over time, but typically don’t lose more than 10 to 20% over 25 years.
Power Output Degradation
To understand how power output degradation works, refer to the graph on the right. In this example, we have a solar panel with a 90% power output warranty for 12 years and an 80% power output warranty for 25 years.
If your panels degrade faster than intended, you can work with the manufacturer to get repairs or a replacement under warranty.
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Rooftop Solar
Solar energy in the United States has exploded over the past decade. In 2010, 667 megawatt (MW) was installed in homes. By 2020, this had increased by 27 times to over 18,061 MW.[1]At the same time, the cost of a residential solar system has come down to half of what it was, even before incentives are applied, and continues to drop. Rooftop solar has increasingly become an option for many households across the country. Many areas offer attractive Renewable Energy Credits (RECs) that, when coupled with federal and local incentives, can make rooftop solar an attractive financial choice that is also good for the environment.
Use this buying guidance to learn more about your options, how to ask the right questions of contractors, and to determine if rooftop solar is right for you.
Start with a home assessment to understand your home’s condition and eligibility.
If your roof needs renovations, it makes sense to replace it before installing solar panels to avoid having to remove and reinstall the panels at a later date. Make your roofing company aware that you will be installing solar panels and ask them if they will come back after they are installed to ensure the panels have not damaged the roof.
The direction and pitch of your roof are important. The amount of energy produced is impacted by how much sun the panels receive, so shadows, trees, other homes or buildings can impact your ability to maximize solar production. Google Project Sunroof is a tool that can address most of these concerns. This tool uses images from Google Earth and analyzes the roof shape to provide you with a personalized solar plan, taking local weather patterns into consideration. PVWatts is another tool from the National Renewable Energy Laboratory (NREL), which uses information you provide to help you determine if solar is right for you.
It is important to understand the regulations in your area (even down to whether the Homeowners Association has any guidelines surrounding the installation) and to know your electricity consumption (kWh) and rates.
Net Metering is an utility policy which allows consumers in some areas to receive a credit on their electricity bill by returning any unused solar electricity they generate back to the grid. Some states and service territories are compensating for excess electricity at rates lower than what a customer would typically pay for electricity. To maximize the financial benefits, it is recommended that the system is designed in accordance with your electricity usage to ensure optimal savings over time.
Buy or Lease? What is the best option for you?
The decision to buy or lease a solar system will depend on your finances, state laws and utility policies.
If you decide to buy a system, you:
- reap the benefits of the electricity produced;
- would be entitled to tax credits or other incentives;
- are responsible for system maintenance;
- can sell the system, if you move.
On the other hand, if you lease a system:
- the solar system company owns it and is responsible for its maintenance.
- You can enjoy cheaper electricity with very low or no upfront costs and monthly payments at agreed rates.
Before signing the lease, ask about your options in the event you decide to sell your property. Zillow has estimated that homes with solar panels sell for 4.1% more compared to homes that are not powered by solar power.[2]
Buying the solar panels directly could unlock additional dollars. First, if you purchase the system there are federal tax incentives through 2023. Your local area may have additional incentives in place to further reduce the cost of the system. Also, there are benefits through Renewable Energy Credits (RECs), that may be sold. The rates received from the RECs vary greatly by state so it is good idea to discuss with your solar provider on what those numbers are. Finally, there is also the electricity generated which will lower some or perhaps all of your electric bill depending on the month. Keep in mind that solar production will be dependent on the season so you should expect more production in the summer and less in the winter. The sum of these savings (tax incentives, RECs, and electricity generation) can be great. In 2016, Consumer Reports estimated that a New Jersey home which purchased a solar roof in cash could result in about 60,000 of savings over 20 years. If the family took out a loan for the entire project, there were still 20,000 in savings over the same 20 year period. [3]
If you lease solar panels, you generally pay the solar company a monthly rate and the solar company continues own the panels and provide maintenance. You can get the benefits of the electricity generation without the upfront cost. However, there are fewer direct financial benefits as customers in the leasing model do not have access to the RECs nor the tax credit and other state financial incentives. With that said, there are still benefits. In this case, Consumer Reports estimated the benefits from leasing to be at 25,000 in savings over 20 years.[4]
Questions to ask your solar provider when getting a proposal.
As with any large purchase, it pays to get multiple quotes. NREL recommends requesting multiple quotes. Remember that there is likely to have been someone else in your neighborhood that has installed solar on their home so check your neighborhood listserv for recommendations. As you obtain quotes from those solar providers, consider this list of questions to ask so that you can get a sense of their work quality and the financial benefit of the system.
- How many systems has the solar provider installed in the past year?
- What is the system size and total installation cost?
- How much electricity will the system generate over the course of a year and what will be the total approximate savings of the system?
- What upgrades does my home need? Would I need a new roof, updated wiring, clearing of trees updated utility interconnection?
- How will I be reimbursed for any excess electricity produced? Does my jurisdiction allow net metering?
- What does the warranty cover and who is responsible for maintenance and cleaning?
- Who is responsible for utility interconnection, permissions, and inspections?
- What happens if I decide to sell my home? What are the conditions for new occupant?
- Who should I contact if my system fails?
- What to do in the event of a blackout?
- If you are considering leasing as a model, consider:
- What is the length of the lease?
- What is the upfront cost and how much do I need to pay over time? The terms may be different depending on the provider so make sure to do the math on how it breaks out.
How to select a solar provider?
Once you have your quotes, it is important that you get the best deal and closely examine the underlying terms and conditions. Look for an installation company that is licensed, has credentials from a certified body, such as the North American Board of Certified Energy Practitioners, and is insured. A good solar provider will offer you a variety of panels and inverters adhering to your aesthetic requirements with appropriate performance warranties. Have them walk you through the options and think about how the panels will look on your home so that you are happy with the result. Keep the warranty in mind. String inverters typically carry a 10-year warranty while micro-inverters can go all the way up to 25 years. Solar panels usually carry a 20-year warranty.
Make sure to compare the average wait time, scheduling, and project completion times for different providers. Lastly, the best provider will be completely transparent about savings, associated assumptions, system monitoring, maintenance and all the estimated costs. The Solar Energy Industry Association’s (SEIA) National Solar Database includes a list of manufacturers and installers across the United States.[5]
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
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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.
Maybe it’s time to call in a solar energy pro. Get free, no-commitment estimates from experts near you.
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.
Why Install Solar Panels in Your Home? Should You Go Solar in 2023?
New tax incentives are making the idea of solar panels more enticing, especially with higher electric and heating bills. Here are some things to consider.
Rising energy and new tax incentives for green home improvements this year are heating up interest in solar.
Experts say it’s a good time for many homeowners to harness solar energy. Though solar power may not work for every home, when it does it can drastically cut home heating bills and lessen damage to the environment caused by the burning of fossil fuels. And while installing a solar energy system is still not cheap, the up-front cost has gone down significantly in the past 10 years.
Cost of solar panels
Costs vary from state to state and depend on things like the size and quality of the solar array. Nationally, the average cost for a residential photovoltaic system is about 20,000 after 30% in federal tax credits, according to EnergySage.com, an information website for residential alternative energy.
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Nick Liberati, communications manager for EnergySage, breaks it down: The national average for a 10-kilowatt system, priced at the national average of 2.86-per-watt, costs 28,600. The federal tax credit allows you to deduct 30% of the cost of installing solar panels from your federal taxes (or in this case, a total of 8,580), bringing the cost to 20,020.
On average, it takes 8.7 years to break even — that is, to save enough on power to recover the cost of solar panels. After that, your solar energy is free until the equipment wears out. Solar panels are typically guaranteed to last 20 to 25 years, although the system’s inverter is generally guaranteed for 10 years. The inverter converts DC electricity generated by solar panels into AC electricity that’s used in your house.
Should you buy a solar panel battery?
The average solar panel cost quoted above doesn’t include storage. A battery can add an average of more than 9,000 after the federal tax credit, depending on the size and other features. Specifically, Liberati says, the national average cost for a battery in the 10-12 kilowatt hour size range is about 13,000. Starting in 2023, all residential batteries will be eligible for the full 30% tax credit as long as they’re over 3 kWh in size. So you’d be able to deduct 3,900 from your taxes, leaving you with a post-tax credit price of 9,100 for the battery.
Although batteries are becoming more popular, most solar houses don’t have them. Instead, most consumers send their excess energy to their utility as credit toward their power usage when the panels aren’t collecting enough, such as at night.
Without a battery, if your utility loses power, your home does, too, even when it’s sunny. “The primary reason for this is safety,” Liberati says. “If your solar panel system is still producing electricity and sending it to the grid during an outage, those energized wires pose a serious safety threat to any utility workers trying to restore electric service to the grid.
That won’t be a problem if you have a battery with “islanding capability.” Islanding is a technology that allows your home to support itself. “You can keep producing solar energy and feeding it to your battery during an outage without posing a risk to line workers because a system that is islanded won’t push excess electricity onto the grid,” Liberati explains. He notes that not all solar panel systems with energy storage can automatically island. If you get a battery, you should make sure your installer gives you the right equipment to enable this technology.
Things to consider when getting solar panels
With so many thousands of dollars required upfront, going solar can be intimidating for many people, notes Vikram Aggarwal, CEO and founder of EnergySage.
Aggarwal urges comparison shopping and checking any claims — such as that your utility or the government will give you solar for free. EnergySage, he says, helps with this and connects consumers with reputable contractors. The site also has information about incentives offered by different states.
Another factor to consider is how your utility company credits you for the solar energy it gets from you, particularly if you don’t have a battery and are reliant on the utility to run your home when your panels aren’t collecting enough.
Michael Ware, a senior solar specialist with consulting firm EcoMotion, says there’s tension over how the utilities credit customers for solar power. The utilities want a discount, similar to how they pay for other forms of energy that they sell to consumers. But solar advocates want the utilities to credit customers the full amount they have to pay for their power, known as net metering.
Sherri Shields, director of communications and marketing for the Florida Solar Energy Center at the University of Central Florida, said people who install solar should check with their insurance companies about whether they cover the panels or whether you have to purchase extra insurance.
Other reasons to go solar
Saving money is just one reason people go solar, notes Robert Stoner, deputy director for Science and Technology of the MIT Energy Initiative. “I think most people who invest in residential rooftop solar simply want to be part of the transition, and to a lesser degree to be seen to be,” he says. “Nothing wrong with that…Some, like me, own homes — my weekend home is at the end of a five-mile-long barrier beach — that simply don’t have the option to have grid electricity.” Stoner says his solar system, which includes a bank of lead acid batteries, provides all of his electricity, “And it brings me a lot of joy! Some of that comes from the feeling of independence I get, and some of it from getting to experience the miracle of electricity being produced from the sun.”
Rotraut Bockstahler, 86, of Sarasota, Fla., with her husband, installed 26 solar panels and a Tesla battery in November 2016. Installing the solar panels cost just under 28,000, and they received a tax credit of about 8,400, leaving a net cost of about 19,600. Getting the battery cost about 8,400, and they received a tax credit of about 2,500, for a net cost of about 5,900. “We feel strongly about climate change and wish to make a contribution to reverse that trend,” Bockstahler says. Going solar “was one of the most positive decisions we made for our living in Florida. We have saved money, made a contribution to fighting climate change and were fortunate enough to have electricity every time there was an outage in the electric grid.”
Going solar doesn’t always cut you off from the power company entirely. When the system was first installed, Bockstahler says, their need for electricity from the utility dropped significantly and their power bills went down to about 40 to 60 a month. With increasing energy costs, they’re now over 100 a month. But in addition to the power bill savings, she counts the money saved on food that didn’t spoil and hotel rooms they didn’t have to get when the power grid failed.
If they have any regrets, she says, it’s that they didn’t get a bigger system. “We feel that the decision we made about the number of panels we have, was maybe a little too conservative and should have included more circuits that could be powered by the battery,” she says.
Should you wait for new solar panel technology?
Another reason you might hesitate to go solar is that technology might advance to offer more efficient and/or less expensive options. And it’s true that different technologies continue to emerge. For instance, some companies are offering roof shingles that serve as solar collectors. Also, standard solar panels have become more efficient, less expensive and better looking.
If you wait, might you have a chance to get something better?
Aggarwal says solar panels do improve slightly each year, but not enough to justify waiting for a dramatic change. A decade ago, he said, the panels would each generate maybe 240 or 245 watts. Now, they each produce 400 or 420 watts of power. So this means, you can get more power from a system that covers the same amount of roof space. The panels, he says, used to be bright blue with silver around the edges. Now, they’re all black and “look beautiful,” he says. And they’re more durable.
Solar shingles, he says, so far haven’t turned out to be ready yet for broad use. Aggarwal says a roofing company plans to introduce “an interesting product” along those lines sometime this year. But solar shingles are still less efficient and more expensive than traditional solar panels. However, if you’re planning to replace your roof, he says, solar shingles may be worth considering.
Ware said he expects the price of batteries to come down in the next five or 10 years as companies explore different battery technologies. The currently most popular battery technology is lithium-ion, which may pose a fire hazard in some instances, leading some jurisdictions to require that they be mounted outdoors.
Is solar right for you?
Some homes are not suitable for solar:
- If you have an old roof that needs to be replaced in a few years, for example, it makes sense to wait because removing and reinstalling solar panels can cost thousands.
- If your roof faces north or is in the shade, you probably aren’t a good solar candidate.
- It’s also more complicated and expensive to install solar on roofs covered with clay tiles, Liberati says.
There is another option for people who can’t put solar collectors on their roofs.
Community solar involves an array of solar panels that people can purchase an interest in. People who participate in community solar generally receive credit from their utility company for power generated by their share of the project. You can find information about community solar projects in your area on the EnergySage website.
Note: This item first appeared in Kiplinger’s Retirement Report, our popular monthly periodical that covers key concerns of affluent older Americans who are retired or preparing for retirement. Subscribe here if you want retirement advice that’s right on the money.