Solar Panel Installation

Do you want to know what's involved in a solar panel installation? The experts at NimbleFins explain where to find a solar panel installer, how much installation costs and what's involved in a residential solar panel installation. By the end of this article you will know the basics of solar panel installation for your home.

Solar Panel Companies

Solar panel 'companies' can refer to equipment manufacturers, but typically people looking for 'solar panel companies' are really thinking of installers, as these are the companies who deal directly with the consumer. (If you want to learn more about the best solar panel equipment manufacturers, check out our solar panel product comparisons and list of best solar panels.)

You'll probably find that a given installer primarily works with certain equipment manufacturers, but not others. In particular, the larger installers might have a fixed product list—if you want certain specific equipment, you might need to hunt for a suitable installer, and a smaller installer might be more willing to source and install specific equipment for you compared to a large installer (they can be more 'corporate' with less wiggle room to stray from the norm).

What determines which manufacturers an installer chooses to work with?

The reasons can vary, but installers typically look for quality products that won't cause issues for their customers; and they often like to offer a range of products (e.g. a lower cost option, a higher quality option, perhaps niche products to help in shadier environments, etc.). Even when choosing 'value' products, an installer certainly cares about a minimum level of quality as well, because the installer is often the first point of contact for a customer who has trouble with their system—and any installer certainly wants to minimise customer complaints about faulty or poor-quality equipment.

Installers will try to negotiate good deals with certain manufacturers, which they can pass on to customers to remain competitive in the marketplace.

But which solar panel installers are best?

Solar Panel Installers

There are two main types of solar panel installers:

  • Energy Suppliers: Octopus, E.on and Scottish Power have internal teams that install solar panels. In our experience, energy companies may not be as desirable for solar PV installs because of a combination of factors like more cumbersome quote processes, less choice of equipment (e.g. for shade) and reduced geographic coverage. FYI most big energy suppliers that don't have their own solar install teams have partnered with specialists like Effective Home and Fusion8. We also found them to be more expensive than the specialist installers.
  • Specialist solar PV installers: From small and local to large and national (e.g. Effective Home, GlowGreen, etc.), there is a host of companies in the UK that specialise in solar panel installation. Some of these only do solar, while others work with other 'greener' products like heat pumps, and you'll also find some traditional heating companies moving into the solar space (e.g. Heatable).

Looking for an installer? Read our article about the best solar panel installers.

Solar Panel Installation Cost

While a typical system costs from around £7,000, the cost of solar panels depends primarily on the size of the system (e.g. the number of panels/the solar power generation) but other factors like the installer, discounts, and the specific equipment have an impact, too.

The government has gathered data showing the costs have trended up in the past few years:

Chart showing solar panel pricing trends 2013 - 2023

But our team has found that real-life quotes for a typical home can be cheaper than £2,300 - £2,500 per kWh, due to more and more competition in the solar market and installation discounts. In fact, the average over dozens of quotes we personally received, the average cost was just under £2,000 per kW. Learn more in our article about solar panel installations costs, where we share real-life quotes and experiences from 2024, charting costs for different system sizes.

What happens with a solar panel installation?

Photo of residential solar panel installation

There are a series of events that occur before installation, during installation and after the system is commissioned. We've detailed them below:

Before installation day

  • Permissions and approvals: Your installer should be able to advise you regarding any approvals and permissions you might need. In most cases, roof- or wall-mounted residential solar panels don't require planning permission as they typically fall under 'permitted development' rights. Exceptions could be listed buildings, flats and properties in conservation areas. Note, renters need the landlord's permission!
  • Remote survey: Most of the larger installers will start with a remote survey, as this is more efficient for them than sending someone round. During the remote survey, which helps determine the suitability of solar panels for your home, you would show the surveyor round the relevant parts of your home via a phone video call. They'll want to see locations like the front and back of your home, your fuse box/distribution boards, electricity meter and the main fuse. You also have to show where your electricity meter is, and locations that could suit a solar panel battery (if you're getting one).
  • In-person, on-site survey: In some cases, the remote survey is not sufficient and your installer will also schedule an on-site survey. You'll need to be home for this in order to provide full access to the property including the loft, garden, all rooms, garages and conservatories and your heating and metering cupboards. Be sure the house is orderly because the surveyor will need clear access. The surveyor may take photos and ask further questions. Your surveyor should also discuss your electricity needs again to confirm you have the correct number of panels.
  • Scaffolding: Any scaffolding is usually erected 2 to 3 days before installation. This activity will typically be arranged by your installer and outsourced to a specialist scaffolding company. The cost of scaffolding should be included in your solar panel quote.
  • Smart meter: If you don't already have a smart meter, you can contact your energy supplier to install one before your solar panels arrive. A smart meter records the export and import of electricity separately, displaying readings on the display. A smart meter is necessary if you might ever sell extra solar-generated power back to the grid on a SEG tariff. Alternatively, your solar panel installer may be able to fit a smart meter with the installation; and you can always retrofit a smart meter later. Discuss this with your installer.
  • Equipment delivery: Some of the solar panel equipment may be delivered to your home ahead of the install. Be sure not to open any of the packages and store them in a safe environment.

Installation day

Depending on the number of panels and the difficulty of the site, solar panel installation typically takes between 1 and 3 days.

Wondering how the installers actually attach the solar panels to your roof? The NimbleFins team went to the Solar & Storage Live event in London, April 2024, where we watched a solar panel installation demo by ESDEC. We thought this demo was particularly interesting because their system does not involve screwing anything into your roof—the mounting system has roof hooks that essentially 'pinch' the tile, holding the hook in place. Once four of these hooks are in place, horizontal mounting rails are snapped into the roof hooks. And once the horizontal rails are in place, a solar panel is laid onto the rails, and finally, mounting brackets clamp and secure the panel.

Here is a video of the demo we watched:

Solar Panel Installation Demo

Your solar PV system involves more than just panels. An installer will typically install:

  • Solar panels: The heart of the system!
  • Fuse box: A small consumer unit is placed next to your existing consumer unit/fuse box
  • Inverter: To convert the DC electricity into AC, which can then be used to power your home (installing a battery now or in the future? If so, this should be a 'hybrid' inverter, which will cost a bit more); this often goes in the loft, if there's room
  • DC optimisers: To maximize the energy production, especially for situations where panels may be shaded for part of the day (e.g. due to trees or chimneys)
  • Bits and bobs: Various other bits like brackets, cables, isolators, a wifi stick, bird guards and more, as needed
  • Battery (optional): to store any excess electricity that's generated and not used right away; the battery often goes in the loft next to the inverter, if there's space
  • Export meter (optional): To measure how much energy your panels generate, and how much of that is exported to the grid

If not carried out during an on-site survey, professionals will check your roof before installation begins to ensure it can handle the added weight of the solar panels.

Before the installer leaves, be sure they have provided all documentation regarding any guarantees and warranties, test certificates, and other paperwork relevant to your goods and installation. Ideally you get this at the time your system is commissioned (you lose power once they leave the premises and you've paid in full!), but no later than 10 days after completion. The installer should fully explain the terms of the guarantees in writing, but get a verbal explanation as well so you can go through any questions that arise.

Installation should be carried out in compliance with the HIES Consumer Code and MCS requirements.

Currently, many installers have a couple-month-long queue for installation. So if you want solar panels on your roof before summer, be sure to initiate the process a couple of months in advance. And beware that installation may be delayed due to factors like severe weather, problems sourcing or transporting equipment, scaffolding delays, or if you've had delays getting finance, planning permission or approval from the DNO.

After installation

  • Scaffolding: Any scaffolding will be removed once the installer is happy your system is up and running properly.
  • DNO application: If you might earn some extra money by selling unused, solar-generated power back to the grid on a SEG tariff, your installer will apply to the DNO on your behalf. This process can take up to 60 working days and the DNO may charge ~£360 for the application.

How long does solar panel installation take (and do I have to be home)?

Standard solar panel installs can be completed within 2-3 days, and bigger installs can take between 3-4 days.

You typically need to be around for the on-site survey, and whilst the panel installer does the wiring, which takes a few hours.

Do I need planning permission?

The only time you will need planning permission to install solar panels is when the property is listed or in a conservation area. And some flats may need permission. If you are renting your home, the landlord will need to provide written approval as well.

For larger installations (e.g. 12+ panels) where your system will require a 5kWh inverter, the installer will need to permission from your distribution network operator (DNO). This can take a few of weeks.

Additional works

Your solar panel installer may recommend additional works.

  • Fire protection: If inverters or a battery are installed in a remote location like a loft space, it may be necessary to link fire detection equipment to a sounder elsewhere in the building, where it can be heard.
  • Loft access: If solar equipment is installed in a loft space, your installer may recommend that lighting and a loft ladder are installed for ongoing access to the system.
  • Chimney stack removal: One installer suggested we remove a chimney stack that is not in use and would shade our south-facing panels to varying degrees throughout the day (FYI we were quoted £1,500 for this).

You may need to contact a third party specialist to complete any of these recommended additional works.