What happens on the day of a Solar PV installation

The day of your install arrives, heres what to expect:

Here's a detailed step-by-step guide focusing on the day of installation for a solar PV system on a domestic property. Sometimes the installation might span over a couple of days depending on the size of the system, weather conditions, and any unexpected issues that may arise but for most systems, the installation should not take longer than a day and typically, the install can be completed in half a day. 

1. Scaffolding Erection:

Safety is the top priority during the installation process. For your installation to begin on time,  scaffolding is normally erected a day or so before the installation. The scaffold provides a safe platform for the installers to work from, allowing them to access the roof and carry equipment safely.

2. Installing Roof Anchors and Mounting Frames:

The first step is the installation of the roof anchors. These are bolted to your roof rafters to provide a secure foundation for the mounting frames, ensuring that the panels will be firmly attached to your roof. It's crucial to waterproof the site of anchor installation to prevent any potential leaks. Roof tiles will be temporarily removed to expose the rafters which the hooks will be fixed onto. Once in place, the tiles are put back to their original position. Sometimes, the tiles will ‘kick up’, because a part of the hook is pressing on the tile making it jut out. If it is left like this, the roof will not be water tight and leaks will occur. Therefore, the installation team will grind out the part of the tile that is causing it to poke out from the roofline. Once it has been ground down then the tile is then placed back and fits snug, ensuring water tightness is restored. 

Following this, the mounting frames (also known as racking) are attached to the anchors. These frames are designed to hold the solar panels and are positioned according to the design plans for the optimal orientation and angle. The frames span the length of the roof (or the length of the design), and they normally come in 3 metre or 6 metre lengths. 

For more information on this part of the process, check out our other blog post here, which talks in depth how a Solar P.V. system is fitted to a roof. 

3. Panel Installation:

Once the mounting frames are in place, the solar panels are then lifted onto the roof. The panels are securely bolted to the mounting frames, ensuring they are evenly spaced and securely fastened.

They are fixed to frames using clips that are drilled into place to securely fasten them. Each panel has 4 clips, top left and right, and bottom left and right. 

4. Inverter Installation:

The inverter, which converts the direct current (DC) produced by the solar panels into alternating current (AC) usable in your home, is typically installed in the loft space or near to the home's main electrical panel, (maybe in a garage or utility area). It's securely mounted to a fireproof backed board and then connected to the home's electrical system.

An inverter converts the DC energy produced by solar into AC

This requires cabling from the inverter to the main consumer unit in the house. Your installer will need to find a way to cable from the inverter to the location of your consumer unit. They will look for the best way to do this, ideally finding an existing route where they can run the cables. Sometimes this isn’t possible and some surface mounted cable (then covered by conduit, plastic trunking) is required in areas. There is also the option of pushing the cable externally, running it down the side of the house and then back into the house on the ground level, as close to the consumer unit as possible.

5. Wiring:

Next, the panels are wired together (in series, referred to as strings), and these wires are connected to the inverter. The wiring is generally concealed for aesthetic reasons and to protect it from weather.

6. Installing the Battery (if applicable):

If your system includes a battery for energy storage, it will typically be installed at this stage. The battery is connected to the inverter, allowing it to store excess electricity produced by your solar panels for use when the panels aren't producing electricity, such as at night or during periods of heavy cloud cover.

7. Grid Connection and Meter Installation:

The final step of the installation is connecting your solar system to the electricity grid. This involves installing a new meter capable of recording not only the electricity you use from the grid but also the excess solar energy that your system feeds back into the grid. Depending on your system size, the grid will need to authorise the installation. Your installer should have already obtained approval from the grid, if the system is under 3.64kWp, then they can notify after the installation has been completed. 

8. System Testing and Commissioning:

Once everything is installed and connected, the system is then tested to ensure everything is working correctly. This involves checking all connections, ensuring the inverter is working correctly, and confirming the panels are producing electricity as expected, the installation team's electrician will perform voltage checks here. If all checks out, the system is then commissioned, marking the official completion of the installation. The MCS certificate for the system can now be created.