Solar energy is a free and clean source of power for all of us, but in order to get energy from the sunlight we have to use solar panels installed on the roof or in the yard.
The reason why solar PV systems are usually installed on the rooftop of the house is the shade that could affect the PV system that are ground-mounted.
The Reason to Install a Solar PV System on Your Roof
Installing a solar PV system is not cheap today, but if you learn how to do it yourself, you can save a lot of money.
You can buy solar panels from many places, but it is better to find a company that provides DIY kits, along with the custom installation plans that you need to get the permits from your city.
Once shipped to your property, all the parts of the solar PV system that you are going to install on your roof must be there to be able to start the installation.
Every house has different roof lines and energy needs, but the custom installation plan created by the DIY company specific for your home must include the wiring diagram and the position of the panels on the rooftop.
Attaching the Racking System to the Roof
The installation must include at least two persons (you and a friend or a member of your family).
Once climbed on the roof, you have to start by establishing the perimeter of the panels using a lumber crayon and a chalk line to visualize where the panels are going to be installed.
Installing the Rails that Hold the Panels
In order to attach the racking system to the roof, you have to find the location of the trusses that are underneath the shingles and the plywood.
You can drill a hole in the roof and then go in the attic to measure the distance between the hole and the closest truss, but if you don’t like to make holes in the roof for nothing, you can simply use a hammer.
While gently hitting the roof with the hammer, you will hear a difference between the loose area of the roof and the solid area of the roof where the truss is located.
Once you find the first truss, all the other trusses must be located in the same spots on the roof.
Before attaching the rails that hold the panels, you have to install the flashing using a sealant to fill the hole and put some more sealant in a U shape around the hole on the back of the flashing before installing the lag bolts (the flashing and the sealant will keep water away of the roof).
Use the Truss to Attach the Rack for Your Solar PV System
Always drill in the truss to attach the lag bolts, because the rack and the panels are quite heavy.
Put the flashing underneath the shingles and install the lag bolts one by one.
When installing the rails you can choose a snap and lock system or an adjustable up and down system that could help you level the rails much better.
The channel inside the rails will hide the wires and the PV cables coming from all the panels installed on the roof.
If you use micro-inverters, their wires will be hidden in the same channel inside the rail.
Installing the Roof Junction Box
To install the roof junction box you have to drill a larger hole in the roof.
This must be done where you have attic space to hide the cables. To waterproof the hole, you will use the same sealant put on the back of the junction box in a U shape around the hole.
The shingles will just fit down over the flashing, and no water will get into the attic space.
The cables connecting the panels together (or the micro-inverters) are called trunk cables and are used to bring the power down to the roof junction box.
Cables and Solar Connectors
Lay the trunk cables inside the rails and zip tie them together with the other cables that could be ZW wires to keep them safe.
From the roof junction box, another set of cables will bring the power down under the roof.
Install the system ground by connecting a copper wire to each rail on the roof to transfer the electricity right into the ground in case of any electrical anomalies such as faulting or lightning.
Installing the Panels on the Roof
Once you have the racking system firmly attached to the roof, you can install the panel one by one.
Each panel has two wires on the back that will plug into an optimizer or a micro-inverter.
The energy produced by the panels will be sent through the trunk cables to the roof junction box, and from there down to the boxes installed there.
When using the snap and rack system the installation is faster because you will use a reduced number of tools (a Philips head screw or a half inch sprocket).
Once you’ve finished installing the panels, you can cut off the excess rails.
Warning!!!
When working with wires and the electrical part of the solar PV system remember to follow local code and also your plan set.
If you don’t know what are you doing, I suggest you to hire an electrician.
Especially if you install a grid-tie system, you have to call an electrician because you don’t want to harm yourself or ruin the panel that powers the house.
After installing all the boxes and the wires of the solar PV system, you will have to work with live wires.
Use the Service Provided by a Licensed Electrician
If you haven’t done it yet, now is the moment to call an electrician to make all the connections required in the proper way.
In the next step you will change your meter with one that reads power going both directions, and you will need to pass the final inspection.
If you install an off-grid system, you don’t have to hire an electrician (you are not dealing with energy from the grid), but you will have to install an energy storage system (a battery system) to store the excess energy produced by the panels.
That energy will be used during the night or in the cloudy days if you have a larger battery system.
Once the solar PV system is online, you will start producing energy for at least three decades.
The PV system will pay for itself in about eight years, but once you start using solar energy to power your home, the carbon footprint of your building and the energy bill will be significantly decreased.
Financial Incentives For Going Solar
Incentives can help you get the solar PV system at a more affordable price.
The 26% tax credit applies as long as the home solar PV system is installed by December 31, 2020, and in the next year (2021), the tax credit will step down to 22%.
The tax credit will continue to decrease so why to wait a few more years?
Go solar as soon as possible because you can still use the incentives to lower the price of your PV system, and besides reducing the amount of greenhouse gas emissions produced by your home, you will also pay less on energy bills.
