In this video, we’ll show you how to find the best and most cost-effective solar panels for your house. On average, more than 4,000 solar panels are installed in the UK each month. This popularity has naturally meant that the price of solar panels has also steadily gone down, so much, that since 2010, the price of solar panels has decreased by 60%. With our 6-step guide, you will learn how to choose the most affordable, high-efficiency solar panel system that will not only save you money but make your home more sustainable. I'm Sue-Angel from GreenMatch, and if you're considering going solar keep watching! Step 1: Calculate Your Energy Needs The first thing you'll need to find out is your household energy needs. In the UK, an average two-person household will consume 2,000 kWh per year And an average four-person household will consume 3,500 kWh per year. First, you'll need to decide if you want your solar panels to cover your full energy expenditure or only parts of it. Then, take a look at your energy bills over the last year and find the average energy expenditure of your household.
To calculate the number of panels you need to cover your full energy expenditure, divide the hourly usage of your home by the wattage of the solar panel. You should do this for both a low and high wattage panel solution, in order to get a range of the sizes. This will give you a realistic expectation. Also, remember that the solar panel system will not cover your energy needs every hour of every day.
But if you have a grid-connected system, you can use the energy grid as a storage system to deliver to when you have a production surplus, and take back when you need it. Step 2: Figure Out Your Roof Capacity Now that you’ve figured out your energy needs, you need to look at your roof capacity. This will determine how big of a solar panel system it can hold. To figure out your roof capacity you'll need to look at the three following factors: Roof suitability, roof size, and roof support strength.
These will all affect the type of solar panels you should get, and also how many solar panels you’ll need. Factor one is roof suitability. The ideal roof would be one that is facing south – at least if you're in the northern hemisphere. This way, the solar panels will be exposed to sunlight for as long as possible. If your roof isn’t completely south-facing, then southeast and southwest-facing panels will also work. Just know that the less south-facing, the less effective your solar panel will be. The angle of your roof is also an important factor in determining your roof’s suitability. Flat roofs are most ideal, and sloped roofs can also work. If the roof is sloped, then any angle between 30° – 40° is best. You will also need to think about shade. If your roof gets covered by shade from another building or tall trees for long periods during the day, then this wouldn't really be ideal. Also, remember that solar panels can last as long as 40 years, so make sure you don’t need to replace your roof in the near future. Factor two is roof size. The best roof for your solar panels will be a large, square roof.
When calculating how much roof space you'll need, you have to consider things like chimneys and skylights that deduct from roof space. Solar panels need to be at least 30 cm from the edge of the roof, so you'll have to factor this in. If you have access to the loft, you can quite easily calculate the area of your roof. Of course, you can always get an installer to come and measure this for you. Let’s say you are aiming to get a 4 kW system, which is one of the most common sizes for a domestic system. As most solar panels are 250W, you will need 16 panels for this system. 16 panels usually spread out to 23 square metres. With adding that 30 cm of extra space on the edge would mean that you will need a roof of 29.8 square metres. Factor three is roof strength. Nowadays, most roof materials are compatible with solar panels. It’s only slate and wooden roofs that may be a bit too brittle for solar panels.
Though individual solar panels don’t weigh that much, if you add thirteen or fourteen panels, the weight does definitely add up. Let’s say you’re installing a 4 kW system with 13-14 300W panels, which in total will weigh about 250 kg. Not only that, but the framework and brackets and cabling also add up to the total weight. The best way to estimate your roof strength is to hire a specialist to conduct a structural roof report. Now that you’ve calculated your roof space and energy needs, you’re ready to start considering the various solar panels out there to match your home.
Step 3: Choose the Right Type of Solar Panels There are three common types of solar panels: monocrystalline, polycrystalline, which are both silicon-based, and thin-film, which consists of various materials. Let’s go over the silicon-based ones, which cover around 90% of all manufactured photovoltaic panels. Monocrystalline panels are cut from a single crystal of silicon. They look great and have quite a distinctive look, as they typically have an even black colour. They are the most efficient and require less space than others, but they are quite expensive. The rate of efficiency of monocrystalline panels is usually somewhere between 15-20%. Polycrystalline panels, on the other hand, are pieces of silicon crystals melted together. They are more efficient to manufacture, which means they are more affordable than monocrystalline ones. Although, they are also less efficient, with an average efficiency rate of 13-16%. Thin-film solar panels are the least common, but the most affordable type of solar panels. There are four different types of thin-film panels, depending on the photovoltaic material used. They are usually the cheapest option, are light-weight and portable, but they are the least efficient.
You can expect something between 7-13%, depending on the type of panel. They produce, on average, four times less than monocrystalline panels. So, what suits your needs? For example, if you have limited roof space, you’d go for monocrystalline panels, as they're the most efficient and, therefore, you can get the most out of the limited space. If you are on a limited budget, you might consider thin-film panels because they’re the most affordable ones. Polycrystalline panels give you the best of both worlds, with more affordable prices than monocrystalline, while requiring a moderate amount of roof space.
Whichever solar panel type you opt for, make sure that you get an MCS accredited installer. Now that we've figured out what you’re working with, let’s get into the budget! Step 4: Figure Out Your Budget The total cost of a solar panel system consists of four major price components: the panels, the inverters, the support system, and the installation. The biggest variation in your budget will depend on the type of solar panel and the size of the system. So, let’s look at different scenarios: First, let’s take the average house in the UK. A three-bedroom house with 3-4 residents and an annual electricity usage of 3,500 kWh would need a 4 kW solar panel system. This system will consist of 10-16 panels and will cost from £5,500 to £10,000 for the entire system. Let’s compare that with a smaller house, suited for a couple. A two-bedroom house with an annual electricity usage of 2,000 kWh would need a 2 kW solar panel system. This system will consist of 5-8 panels and cost £3,500 to £6,000 for the entire system. Keep in mind that the price ranges are wide because they are dependent on panels, the inverters, and many other factors.
With this, you can get a rough idea of how to prepare your budget for a solar panel system, and you can use this information to initiate a conversation with your installer. Now we’ve talked about the up-front cost, let’s look at how much you can save. Step 5: Figure Out What You Can Save with Solar Panels The biggest savings you will gain in using solar power is the environmental savings that come with using renewable energy. Something, in my opinion, can’t put a price on. Adding to that, you can also cut your monthly energy bills. Considering only the savings on your electricity bill and not the cost for the investment, you can expect the following change: Without solar panels, the average yearly electricity bill for a household that uses 3500 kWh per year would be around £500 in southern UK. If half of your electricity consumption is generated by solar panels, you could cut your yearly energy bill in half to £250. On top of that, you can also add an income of £96 yearly for electricity sold to the grid.
In short, your electricity bills would cost only £154 per year with solar panels, versus a whole £500 without solar panels, cutting almost 70% from your total yearly costs! There are numerous factors that affect when your solar panel investment will break even. For example, the cost of the system, how much energy you will use, the possibility to sell electricity back to the grid and at what price, and the costs of a possible inverter change. The better you take care of your solar panels, the longer they will last, and you can get a greater return on your investment. So, let’s move on to our last tip: how to maximise efficiency with the right maintenance! Step 6: Maximise Efficiency with the Right Maintenance Even though this last step will focus on maintenance, which happens after you’ve installed the panels, it’s important to keep a couple of things in mind before you make a purchase. There are 6 main factors that will affect your solar panel efficiency: Shade, inclination, cleaning, sunshine hours, age, and orientation.
Some of these factors are completely out of your control. For example, sunshine hours are completely dependent on where you live, and your solar panels will eventually age with time. With time the efficiency does lower a bit, usually around 0.5% per year. But most solar panel manufacturers will offer warranties that ensure that even after 25-30 years, the power input of the system will stay over 80% of its original efficiency. However, there are still efforts that you can personally make to make sure that your solar panels are as effective as possible, for as long as possible. First thing that you can affect is inclination. When angled optimally, you can expose your panels to more sunlight. A good idea is to adjust the angle twice per year since the sun moves in different angles during the winter and the summer.
In order to do this, you have to make sure that your solar panels come with an adjustable rack. Another thing that you can do is to clean your solar panels regularly. Cleaning them is important since dust or dirt can accumulate on the surface. This may block some of the sunlight and reduce the efficiency. Fallen branches and leaves will also block the sunlight if they land on your panels. Some panels are self-cleaning, and others you have to clean yourself. So, keep this in mind before making the final decision. If you go for panels that you have to clean yourself, make sure you do it contactless. For example, using a garden hose and avoiding brushes and sponges. And with that last step covered, we’re all done! Now you're prepared to make a decision on the best solar panel system for your home, and you can be confident that you’ve taken everything into consideration.
If you want to get straight into it, head to our site, GreenMatch.co.uk. There, you can fill in our form to receive up to 4 offers for solar panel systems. Our comparison service is completely free and non-binding, and you can take your time to compare the best offers. Click on the link in the description below, if you feel ready to make that first step! Also, if you found this 6-step guide to be useful, do give us a like, it would be much appreciated! And while you’re at it, hit the subscribe button for more green energy related topics from GreenMatch!.