Find a Solar Panel Installer you can trust in Argyll.

• The power of your solar panel system – there's no point buying a higher capacity battery if your system will never generate enough electricity to charge it
• How often you think you will need to charge your battery
• Your budget
• Whether you care about having the latest technology and a recognisable brand name

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.

Solar panels provide an alternative to paying expensive National Grid energy rates, so primarily their first major benefit is helping to reduce bills. Solar PV panels will produce free electricity, whilst solar thermal panels generate heat for hot water and space heating. There are also payment incentives known as the Feed-in Tariff scheme (FITs) (for solar PV) and the Renewable Heat Incentive (for solar thermal) which guarantee a tax-free income for 20 years.

Solar thermal panels work by capturing heat directly from the sun and using it to heat water. This hot water is then passed through a coil to heat the water for your central heating system. Solar thermal systems are compatible with many existing conventional boilers with hot water tanks, and can be set up to feed in to your existing heating system.

Whether solar panel batteries are worth it depends on how much you’re at home and how big your solar panel system is. If you’re at home most of the day and your solar panels only generate enough electricity for you to use while for that day, then a battery probably isn’t worth investing in. However, if you have a large system that generates more than you can use or you’re out most of the day, then solar panel batteries are definitely worth it.

A solar battery storage system works by storing the electricity that your solar panels generated until you need to use it. That’s why they’re great for people that are out all day – your solar panels generate electricity all day whilst the sun’s out, but no one’s home so you’re using minimal energy except for things like your fridge and any appliances on standby. Most of the electricity charges your solar panel battery. Then, when you get home, your battery will discharge, and you’ll use all the solar electricity that your panels generated during the day.

Solar batteries are also excellent for people with large solar panel systems that generate more than they use in the day. Any electricity that you don’t use during the day will charge the battery, so in the evening when the sun goes down, you’ll just use the excess electricity that’s stored in the battery.

To work out whether solar panel batteries are worth it for you, you’ll need to work out how much of your solar electricity you’re using already. If you’re at home and you’re able to run your appliances all while your solar panels are generating electricity, a battery might not be worth it. Also, if you’re receiving export payments from the Feed-in Tariff Scheme (FITs) or the Smart Export Guarantee (SEG), you might want to look at the rate you’re getting paid. If it’s a good rate, it might be more cost-effective to continue exporting unused electricity to the grid. Speak to an MCS-registered installer that will be able to help you work this out.

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.

If you want to test your solar panel system to see if it’s working properly or just to see what output it’s giving, you can do this using a multimeter to measure current, or amps, and voltage.

Before you start, you’ll need to find the voltage (v) and current (A) ratings of your panel. You should be able to find them on the back of the panel. You should also make sure that it’s a nice clear, sunny day to get the best readings out of your panel. You should also check that it’s safe to be up on your roof!

To measure open circuit voltage, you’ll need to make sure that your solar panel is completely disconnected from your system’s regulator and battery (if you have one). Angle the panel towards the sun, and ensure that your multimeter is set to measure volts. Measure the voltage between the positive and negative terminals by connecting the negative contact on the voltmeter to the negative on the panel and the positive contact on the voltmeter to the positive on the panel.

Then, you can move on to the short circuit current. Follow the same steps as the open circuit voltage, but ensure that your multimeter is set at 10A to start with.

Only try to test your solar panel if it’s safe to do so. If your roof isn’t accessible without scaffolding or specialist equipment, consider speaking to an MCS-registered solar company about your concerns. They may recommend that they come to service your solar panel system.

It’s vital to purchase a solar panel system that suits your property. If you’re investing in a solar panel system, it makes the most financial sense to get the biggest one possible. However, whether you can do this or not depends on budget and space.

Here’s an idea of how much roof or ground space you’ll need to install a few different sizes of commercial solar panel system.

Solar panel system size, No. of solar panels, Approximate area required

11kW, 44, 64m²

20kW, 80, 116m²

30kW, 120, 173m²

40kW, 160, 231m²

50kW, 200, 288m²