Solar panel sizes in the UK
If you’re thinking about getting solar panels for your home, understanding solar panel sizes and wattage is an important first step. In this article, we’ll walk you through everything you need to know – without any of the tech talk.
Solar panel sizes in the UK can vary based on their type and efficiency. Standard residential panels are typically around 1.65 metres by 1 metre. But if you’ve got limited roof space, more compact, high-efficiency options are also available. And, while size is important, it's the wattage of each panel that ultimately determines how much energy your solar panels can generate.
It may sound complicated, but it doesn’t need to be. With a little know-how, you can make the most of your space and find the right system for your needs.
What are the standard solar panel sizes?
There are two categories of solar panel sizes: residential and commercial. So let’s start here.
Residential solar panel size
For homeowners, the standard solar panel size is 1.65 metres by 1 metre.
These panels are designed to balance energy efficiency with practicality. They’re compact enough to fit on most residential rooftops, but they’ll still generate plenty of free, green energy. And their sleek, dark colour means they blend in with most roof tiles.
Commercial solar panel size
Commercial solar panels are a bit bigger, coming in at approximately 2 metres by 1 metre. They’re built for larger buildings where space isn’t as tight, like office blocks, factories or farms.
Their bigger size means they can generate more energy. So, they’re a great choice for businesses looking to reduce operational costs and use cleaner energy.
Tips for choosing the right solar panel size
To make sure you get the right size panels for your home, we’d always recommend speaking to a professional installer.
If you book a free survey with us here at Hive, one of our experts will visit your home. This is so we can check things like the position of your chimneys, the direction your home faces, your current energy use and any plans you have for future upgrades.
Then we’ll talk you through our findings to make sure you’re happy with our suggested approach. And we’ll be there to guide you through every step of the process, if you decide to go ahead. You can book a survey in five short steps here.
If you’re keen to do your homework first, here are some more tips to help:
1. Check your energy use
First up, it’s important to take a closer look at your energy use. If you use a lot of electricity or plan to buy electric vehicles at some point in the future, you're likely to need more or higher-wattage panels.
2. Measure your available roof space
Next, work out your roof's dimensions, noting any obstacles like vents or chimneys. The more space you have, the more panels you can install. Or you can opt for higher efficiency panels if space is limited.
3. Think about power over panels
Put simply, higher efficiency panels produce more power in less space. So if your roof is small, you could opt for panels with a higher wattage.
4. Find the right fit for your finances
It’s also worth thinking about the balance between panel size, wattage, and cost. Larger or higher efficiency panels may require more upfront investment, but they’ll generate more energy. This means bigger savings in the long run.
5. Be climate clever
Where you live can play a big part in how much energy your solar panels produce. Homes in sunnier regions may require fewer panels. It’s also worth checking which way your home faces and whether there’s any trees that could stop sunlight from reaching your panels, now or in the future.
How to calculate the number of solar panels you need
Step 1: Work out your annual energy usage
Check your energy statement for the total amount of electricity you use throughout the year. This will be measured in kilowatt hours (kWh).
Step 2: Check the solar panel output
The output of each solar panel is measured in watts. Most domestic panels produce around 400W in ideal weather conditions.
Step 3: Estimate energy production
Your daily energy production is the panel wattage x average sunlight hours.
Step 4: Calculate the number of solar panels needed
Use this calculation: Annual energy usage ÷ (daily energy production x 365) = number of panels .
Step 5: Factor in efficiency losses
The figure above doesn’t take into consideration things outside your control – like the weather or any shade on your roof. These could affect how much energy your panels produce. So we’d suggest adding a buffer of around 10-20% to account for this.
What are the factors that influence what size of solar panel to choose?
Solar panel efficiency
Panels with a higher wattage are more powerful and efficient. This means you can generate more electricity per square meter with fewer panels.
Available space
The size of your roof and any obstructions like chimneys, skylights or vents also impacts the number and size of panels you can install.
Energy requirements
The more energy your home uses, the more solar power you’ll need. Check your energy statement for your annual consumption. But also have a think about any changes you might be planning to make in the future – things like adding an extension or getting an electric car will increase your energy use over time.
Solar panel sizes and wattages FAQs
What are the standard solar panel sizes in the UK?
Solar panel sizes in the UK can vary. But for residential systems, the most common panels are around 1.65 metres by 1 metre. This means they’ll fit comfortably on most rooftops.
For commercial installations, like office blocks and factories, panels tend to be larger – usually 2 metres by 1 metre.
How do solar panel sizes affect wattage?
Historically, size was the main factor in determining the amount of energy a solar panel could produce. Generally, the larger the panel, the higher the wattage – so the more energy it could generate.
However, efficiency also matters. And these days a smaller panel with more energy-efficient cells can produce the same amount of power as a bigger panel with less-efficient technology.
What are the dimensions of a 400W solar panel in the UK?
A standard 400W solar panel is typically 1.65 metres by 1 metre, with a depth of 4cm.
This size panel is particularly popular here in the UK because they’re small but mighty. So you can generate lots of solar power without needing to take up too much roof space.
What are the typical solar panel sizes in millimetres (mm)?
Sizes vary depending on their wattage, design and manufacturer. To give you an idea, here are the sizes in millimetres of some of the most popular makes:
DMEGC (450W): 1762 x 1134 x 30mm
JA Solar (405W): 1722 x 1134 x 30mm
SunPower (350W): 1956 x 992 x 40mm
Tesla (400W): 1890 x 1046 x 40mm
Panasonic (390W): 1722 x 1133 x 35mm
Perlight (450W): 1905 x 134 x 35mm
What are solar PV panel sizes?
Solar PV, or photovoltaic, panels turn sunlight into electrical energy. The standard size for residential PV panels is typically around 1.65 metres by 1 metre. But this can vary depending on their wattage, efficiency and who they’re made by.
Transform your home energy
Solar panels come in a variety of sizes and strengths. The ideal panels for you will depend on your lifestyle, where you live and the size of your roof. Wherever you are in your solar story, we’re here to help.
