Find a Solar Panel Installer you can trust in Crickhowell.

In theory, you can fit solar panels yourself. In practice, it’s worth leaving it up to the professionals.

If you get DIY solar panels and install them on your roof yourself, you won’t be able to apply for the government-backed Smart Export Guarantee (SEG). The SEG pays you for every unit of electricity you generate and send back to the grid, so it’s a scheme well worth signing up for. However, you must have your solar panels installed by a Microgeneration Certification Scheme (MCS)-registered engineer or company, so you’ll miss out if you install the solar panels by yourself.

The other thing to consider about installing solar panels yourself is that you’re dealing with electricity. Electricity is extremely dangerous if handled incorrectly, so if you don’t have any qualifications in working with electricity you could be putting yourself and your family at risk. Connecting DIY solar panels yourself and doing it incorrectly could mean that you give yourself an electric shock or cause a fire. If your home is damaged due to a fire caused by solar panels you’ve installed yourself, it’s unlikely that your home insurance company would pay out.

Before having a go at installing your own solar panels, do some quick sums to see how much money it could really save you. A 3.5kW DIY solar panel kit will cost around £4,000-5,000. According to the Energy Saving Trust, a home in the South East of England where most occupants are out all day until 6pm would save around £100 a year on their electricity bills. That means that you wouldn’t break even until 40 years, but solar panels last around 25 years on average. However, if you have your solar panels installed by an MCS-registered installer and they cost £4,500, you could save £220 a year including your SEG payments. That brings the payback time to around 20 years.

So although the initial outlay is slightly less when you install solar panels yourself, it’s much better to have them installed by an MCS-registered engineer so you can take advantage of the SEG payments.

Just like other major house improvement projects, some specific requirements must be met to allow for the installation of solar panels on commercial buildings. The main reason why these standards and regulations were established is to minimize the risk of the solar system becoming an issue or potential hazard in the unforeseeable future. So if you’re thinking about buying and fitting new solar panels, you’ll probably want to know whether or not you’ll require to submit a planning permission application for approval before you can proceed.

Fortunately, the installation of solar panels on commercial buildings may be “permitted development which mean you won’t have to apply to the Local Planning Authority for planning permission. There are, however, some important limits and conditions which must be put into consideration in order to benefit from these permitted development rights. Some of the limitations include:

• The solar panels must be installed on a wall or pitched roof that should project at a maximum of 200mm from the surface of the wall or roof slope.
• Equipment placed on a roof should not be within one metre of the external edge of that roof.
• Equipment mounted on a wall must not be within one metre of a junction of that wall with another wall or with the roof of the building
• If the equipment is on the roof of a building, the capacity for generation of electricity across the entire site must not be more than 1 megawatt.
• In the situation whereby the panels are installed on a flat roof, the highest part of the equipment should not exceed one metre above the highest part of the roof.

In general, obtaining a planning permission is very important and as such, you must discuss your position with your chosen installation company before you proceed.

• Don’t buy cheap solar panels – while it might seem tempting, make sure you choose MCS-certified solar panels. Any reputable installer will recommend high quality solar panels, which is another reason to have them professionally installed rather than doing it yourself.
• Ensure that your installer uses non-combustible mounting systems and frames.
• Check your system regularly for signs of pests gnawing through cables.
• Keep your solar panel system regularly maintained with proper testing and servicing carried out as recommended by your installer.
• If something doesn’t look right to you, get in touch with your installer and ask – they should be more than happy to help.

How much energy a solar panel produces depends on its manufacturer and exposure to the sun. A good-quality solar panel typically has a power output of about 300 watts per hour, but this can vary from about 240 to 360 watts. How much energy your solar panel will produce per day depends on how many hours of unshaded daylight it’s exposed to.

Here’s an idea of how much energy you could expect a large commercial solar panel installation to produce in a year.

Solar panel system size, No. of solar panels, Annual electricity output

11kW, 44, 9,350kW

20kW, 80, 17,000kW

30kW, 120, 25,500kW

40kW, 160, 34,000kW

50kW, 200, 42,500kW

1. After the installer’s measured up, given you an estimated output and recommended some systems for you, they’ll arrange date to come to your home to install the solar thermal panels. They’ll also let you know if any scaffolding will be required.
2. Next, they will start to fit the panels, or collectors, to your roof. Stainless steel brackets will be provided with the system and they will remove your roof tiles or slates to attach the brackets to the rafters. They’ll then replace the tiles and add waterproof flashing to ensure you don’t get any roof leaks, and add the frame.
3. If you’ve chosen evacuated tube solar thermal panels, the installer will bolt the heat transfer unit to the top of the frame but not install the tubes until nearer the end. This is because the tubes start to transfer heat to the exchanger immediately, and when everything is unconnected this could damage the unit.
4. If you don’t need a new boiler with your installation, a new dual coil water cylinder, pump and system control system will be fitted. It’s best in a loft or upper floor of your home.
5. A new thermal store or hot water tank that will store the heat provided by the solar system is much larger than a standard tank but it may fit in the spot of your old one. The installer will ensure that it’s connected to the mains cold water, your other heating source (such as a gas boiler or biomass boiler), immersion heater, temperature sensors and the solar collectors themselves.
6. Next they will install the pumping station, usually near the water tank. The expansion tank will be installed on the solar thermal loop, which is usually nearby. Its job is to prevent pressure changes that could damage the system.
7. You’ll get a heat generation meter which must be MCS-certified if you want to take advantage of the RHI, and any control equipment that comes with the system will be installed.
8. The installers will then bring the system to pressure by pumping the heat transfer liquid into the system up to a pressure of around 2 bar.
9. Finally, your MCS-registered installer will register your solar thermal system so you can apply for RHI payments of up to £525 per year.
So that’s the process of installing solar thermal panels. Remember – it's always best to use a professional to install any kind of renewable technology.

There are a few trusted companies in the UK that make solar panels. While there are other solar thermal panels out there that are made by Chinese and American companies, we’ll focus on the brands with a longstanding presence in the UK since these are the panels MCS-registered solar companies are likely to recommend to you.

Viessmann, Worcester Bosch, Solar UK and Dimplex make some of the best solar thermal panels in the UK. Dimplex and Viessmann offer both flat plate and evacuated tube solar panels, while Solar UK only offers evacuated tubes. Worcester Bosch’s Greenskies range are all flat plate collectors. Viessmann’s panels come with a 5-year warranty, while Worcester Bosch and Dimplex offer extensive 10-year warranties. However, Solar UK offer a comprehensive 25-year warranty and guarantee that the panels will deliver the same level of performance for 25 years!

We’d recommend choosing evacuated tube solar thermal panels because they are the most efficient. While there won’t be much difference between evacuated tubes and flat plates in the summer, in the winter evacuated tubes are much better at taking heat from the sun than flat plates. Since our winters are long and cold with few daylight hours, we think it makes sense to go with evacuated tubes. However, if your priority is looks over maximising efficiency, you might want to choose flat plate collectors since they sit flat on the roof and look more like solar PV panels, whereas the evacuated tubes will stick out.