Can a homeowner install their own solar system?
Are you thinking about doing a DIY home solar installation? It's possible, especially if you're looking for a small off-grid setup, but grid-connected home solar comes with a few more hurdles.
If you’re interested in home solar, handy with tools, and have experience doing electrical work, maybe you’ve considered doing your own home solar installation.
It’s possible to install your own home solar array. This is especially true if it’s an off-grid system that uses batteries and doesn’t interconnect with the electric grid. Without a grid interconnection, a home solar array is a much more simple DIY project because it’s less technical and doesn’t require the same paperwork and permits.
But even if you want to do a DIY install of your own grid-tied system, you can do it. It’s a lot of work, but if you’re persistent and handy, you can save money over paying a contractor to do the work for you. Just be prepared to handle the paperwork and inspections yourself.
Why would you do a DIY home solar project?
The biggest cost in a home solar system isn’t the hardware: on average, the price of solar panels, racking, inverters, and wiring make up only about 36% of the invoice price.
The rest is what is known as soft costs, and it includes things such as installation labor, other staffing costs, permitting, and company overhead. In fact, the research group Wood Mackenzie says that customer acquisition costs - the amount of money that a company spends on sales and marketing to get each customer - accounts for 23% of the total price.
That’s a huge chunk of what you pay for home solar. If you have the know-how and patience to do your own solar installation, you can end up paying less than half of what it would to have someone do it for you.
What hardware do you need to install your own grid-connected home solar system?
This article isn’t a how-to guide: for that, you’ll need to find other resources. But if you’re just looking for a high-level overview of what it takes to do a DIY installation, here’s a list of things that your project may involve:
- A mounting system for your panels. This is a racking system that holds the panels on your roof or a structure on the ground (see the photo above). A racking system should include clamps for the panels and cable management accessories, such as ties or clips to keep the cables from flapping around.
- Solar panels and wiring. The solar panels clamp onto your rack, and are wired together with cables that connect together using industry-standard MC4 connectors.
- Waterproofing your roof. With a roof-mounted installation, there are footings that bolt through your shingles into the structure below. One of the biggest issues you’ll face is making sure that your work is sealed correctly. Roof leaks can cause expensive damage, so you want your work to remain waterproof for a couple decades. Tile roofs are even more complicated to work with.
- Conduit. Whether you go with a ground- or roof-mounted system, you will need wiring to carry your solar energy to your main electrical panel. The wiring will go inside metal conduit to shield it from damage. Be prepared to either route that conduit down from your roof or dig a trench (in the case of a ground-mount) in your yard.
- Inverters. Your solar panels generate DC electricity. An inverter is what converts that DC power into AC power that your home can use. This will either be a central string inverter that is mounted near your electrical panel, or module-level electronics (such as microinverters or power optimizers) that are mounted next to each panel in the system.
- Electrical panel and other components. The average size of a home solar array in the US is 6.5 kilowatts. That’s a quite a lot of power, and often the existing electrical panel in a home will need to be upgraded to accommodate this. This might involve upgrading the existing panel or adding a new subpanel.
- Disconnect switch. There will be other electrical components that are part of your installation. For example, most local codes will require a switch that disconnects your system from the grid. A combiner box and other wiring-related components may also be involved.
- Utility meter. This is something you won’t do yourself, but will need to coordinate with your electric company. Depending on the compensation scheme for the excess electricity you send into the grid, you will either get a second meter installed or a new bidirectional meter that records the electricity coming into and going out of your house.
But wait, there’s more!
That’s a list of the hardware-related work for a grid-connected home installation, but that’s only part of it. If you want to connect your system to the public electric grid, you need permission from the utility company.
There may also be electrical, fire, and structural regulations that you need to know about, and there are often permits that you will need to apply for. Every municipality is different, so you need to do a little research to find out what is required.
Here’s a list of some things you may need to deal with:
- System drawing/schematic. For city and utility permits, you will often need a system design document. This will include a detailed schematic of the installation layout, whether its your roof or a ground mount. You’ll also need an electrical diagram showing how the system will tie into your current electrical panel and the grid. Finally, this schematic will need a technical description of the equipment being used.
- City/electrical permits. These will vary by the city, but you will need at least a permit for the electrical work. The technical requirements are very specific, and include such things as the distance between the cutoff switch and electrical panel, and even where warning labels and signage must be placed. In most cases, the electrical work needs to be performed or signed off by a professional electrician.
- Structural/engineering review. For a rooftop installation, your city may require a structural engineering review to make sure that your roof can support the additional weight of solar panels and racking hardware. If you’re going with a ground mount, you will probably need a geotechnical engineer to review the soil and proposed foundation to make sure that your solar panels and support structure don’t collapse under their own weight or go flying away on the next windy day.
- Rapid shutdown requirements. For fire safety, the National Electrical Code (NEC) requires that home solar systems have a method to quickly de-energize the system so that electricity is no longer flowing in the wires running across your roof. Microinverters and power optimizer-based systems have this built-in, but if you use a string inverter you may need an additional component to meet this requirement.
- Local fire codes. Many local fire codes don’t allow solar panels to go right up the roof edge, but instead be set back by a couple feet or more. If you’re doing this project yourself, you’ll have to research what your local codes are.
- Utility interconnection application. If you’re tying into the grid, you will have to work with the utility company and find out what their paperwork and interconnection requirements are.
- Metering requirements. Depending on your utility, you may need to either replace your existing electrical meter, or have a second meter installed alongside your existing one.
- Inspections for all of this. You will need to schedule inspections to satisfy these permit requirements, sometimes both before and after work proceeds.
You might not qualify for local rebates
While your hardware costs will qualify for the federal tax credit, there are many local solar incentives and rebates that have their own rules. In some cases, these programs require the work to be done by a qualified installer.
For example, Connecticut’s Residential Solar Investment Program provides a significant rebate of up to $0.358 per watt, but you need to use a qualified local company to be eligible.
It’s also worth noting that the federal tax credit, which is currently 26%, covers the total cost of your installation including installation labor. That’s a rebate that you’ll be giving up by doing your own labor.
You won’t have a labor warranty and will be responsible for your own repairs
The hardware you buy will all have their own warranties and will often be as long as 25 years. On top of that, any good installer will also include their own workmanship warranty, which guarantees that the system won’t fail due to a fault by the installer.
You don’t get that if you do a DIY project. If something fails, you’ll be responsible for doing your own repairs. While you could consider hiring an installer for any future repairs, many companies don’t like to touch systems installed by another company.
Resources for the DIY solar installer
If you’ve decided to do your own solar installation, there are a number of sources that can help you.
Seeking out other people who have done their own installation and can guide you around the pitfalls can be very helpful. One resource is the SolarPanelTalk forum, which has many threads discussing all kinds of technical details involved in installing your own home solar system.
All-in-one solar kits
One of the challenges of putting together your own solar array is choosing equipment that is compatible with each other, especially when it comes to selecting the correct inverter for your solar panel output.
To make this easier on yourself, you could choose an all-in-one solar panel kit like the ones available from GoGreenSolar that package together solar panels, an inverter system, and racking that is compatible with one another.
The kits from GoGreenSolar come in different sizes, from 2 kw up to 20 kw or even more. For a 6 kW system, which is about average for a home solar array, the cost-per-watt is around $1.30.
One thing to note is that electrical equipment such as wiring, breakers, and AC/DC disconnects are not included in the kit, because the specific equipment needed will depend on your home. According to GoGreenSolar, “All these items can be purchased at any electrical supply shop, Home Depot or Lowes, and will typically cost $300 to $500. Our technical support representative will provide a shopping list once your plans are complete.”
Check out the kits from GoGreenSolar to see the selection and latest pricing.
Solar permitting and design services
The permitting and design work can be intimindating. If you want to avoid that work, you can actually outsource it. GoGreenSolar, for example, has a $595 permitting service that will take care of your local permits, site installation drawings, electrical schematics, and electrical calculations needed to pass your local codes.
Although paying for this service will cut in your savings, avoiding the headaches of dealing with City Hall can certainly be worth it. Also, because it’s part of the overall system costs, you should be able to apply the 30% federal tax credit to it.
Solar design and permit service - get latest pricing.
Solar interconnection services
In addition to local permits and electrical codes, you also have to deal with your utility for interconnection. This is an entirely different set of permits and paperwork from those required by City Hall. This paperwork can take up to eight weeks, and if you miss any documentation or details in your application, you’ll have to engage in a time-wasting back-and-forth with the utility company. Utility companies are not generally known for their speed of service, so this could add weeks to the process.
You can outsource this too. By doing that, you reduce your chances of getting something in the application process wrong and delaying your project. GoGreenSolar also offers this service, currently for $400, but use the link below for latest pricing.
Solar interconnection service - get latest pricing.
Should you install your own solar panels?
If you want to save money and you’re handy and confident, it’s definitely possible to do your own grid-connected home solar installation.
However, as you can see from the long list of considerations, you might very well find that you’ll spend many more hours than you bargained for, and it would have been worth to simply pay someone else to do the installation for you.
But for some people who are into DIY projects, the money isn’t the point - it’s just fun to do your own work. If that’s you, go for it! Just make sure that you know all of the local codes and permits that you need before you start.