If you’re interested in getting free electricity you may be wondering whether your roof is suitable for solar panels. The good news is that solar panels are effective on most types of roofs. However, the amount of power they produce is influenced by several factors. An important one is the direction the solar panels face.
This is why a solar panel system is installed on the side of a roof that receives most sunlight. But if this won’t provide sufficient power, you may need to consider panels on the front and back of your roof.
You’ll find out here whether solar panels on both sides of your roof could be a good option. We’ll also explore alternatives to roof-mounted solar systems and standard solar panels.
How Roof Direction Impacts Solar Power
Solar panels generate electricity by harnessing energy radiating from the sun. The more sunlight they get, the more power they produce. This is why solar arrays are typically installed on a roof.
Roofs on most homes are double pitched, with the two sides facing opposite directions. Solar panels are usually installed on one side only – the aspect that receives most sunlight.
A solar array works best on a south-facing roof, which gets maximum sun exposure. The opposite side, facing north, gets less light than any other roof orientation. If solar panels can’t be installed facing south, you can still enjoy the benefits of solar power, no matter its orientation.
Solar energy systems produce an adequate amount of power on roofs that face east or west, although output will be lower. If a solar array on one side wouldn’t provide enough electricity, installing solar panels on each side of the roof could be the answer.
Solar Panels On North-Facing Roof
Solar panels aren’t generally recommended for roofs that face north. They receive the least amount of sun – around half as much as a south-facing roof.
But they’ll still produce some power. And it may be possible to overcome the challenges to some extent by adjusting the installation angle of the panels and minimising shading issues.
Solar Panels On South-Facing Roof
Solar panels work best on a south-facing roof in the UK because that’s where they’ll get most sun. They absorb solar light energy when the sun is at its most powerful and from morning to evening, including winter months, with fewer hours of daylight.
Solar Panels On East-Facing Roof
Solar panels on an east-facing roof get about 15 percent less sunlight than those on a roof that faces south. But they can still cut electricity bills substantially. They generate more electricity in the morning and less in the afternoon.
Solar Panels On West-Facing Roof
Like east-facing solar panels, a solar array on a roof facing west produces a significant amount of electricity. They get less solar energy than a south-facing system but output peaks during late afternoon, when electricity demand tends to start increasing.
Solar Panels On Each Side Of Roof
If you don’t have a south-facing roof, solar panels will still be effective on an east- or west-facing roof, although producing less electricity.
If panels on the easterly aspect of the roof won’t generate sufficient power for your household because of limited sun exposure, installing panels on the opposite side as well will boost output if it gets enough sun.
Solar panels on front and back roof surfaces optimise electricity generation because they capture solar light energy from early morning to late afternoon. The east-facing panels absorb light energy during the morning. The west-facing panels take advantage of the afternoon sun, and together they can be almost as efficient as south-facing panels (though you’ll need more of them to achieve similar results).
Solar panels split between these two roof planes may be particularly beneficial if you live in a smaller home with limited roof space. You may not be able to fit all the panels you need on one side of the roof.
If your house has multiple roof elevations, it may be worth considering installing solar panels directed towards the south, east and west, where possible.
Advantages Of Solar Panels On Both Sides Of Roof
Solar panels on the front and back of a roof generate more energy by capturing more sunlight. The more power your panels produce, the less you need to rely on expensive grid electricity. And the more your carbon footprint will be reduced.
If you decide to sell your home, solar panels can increase its potential market value. An increasing number of buyers are looking for properties with green credentials, and solar panels on each side of your roof are likely to be particularly appealing to them.
Some homeowners believe that a solar array on the two sides of a roof enhances the aesthetics of the property with a more balanced appearance.
Disadvantages Of Solar Panels On Both Sides Of Roof
The main drawback of solar panels on the front and back of a roof is the cost. Dual-axis solar systems are more expensive because you need to buy more solar panels and installation is more complex, especially the wiring connections.
Installing solar panels on both roof elevations costs on average from £6,500 to £14,000-plus, depending on the size of your property. This compares with £4,200 to £9,800 for solar panels on a single roof surface. In addition, you may need to spend more on maintenance to keep a dual-axis solar system at optimal performance levels.
Having solar panels on each side of the roof also potentially doubles the risk of shading issues.
What Affects Solar Power Output?
Various factors play a part in how much power solar panels produce, whether they’re installed on one side or both sides of a roof. These considerations include the angle of your roof and how efficiently the type of panels you choose turn daylight into electricity. But external influences such as shading and seasonal changes are important too.
Roof Shade
Power generated by a solar panel system diminishes significantly if light is prevented from reaching the panels.
If your roof is largely in shade because of nearby properties, you should ask your solar panel installer about optimised systems that mitigate the effects of shading. In some cases, you may need to consider other renewable energy options.
In other situations, the problem of solar panel shading can usually be addressed. You can prune back overhanging branches from trees, for example. And satellite dishes can be relocated.
The Changing Seasons
The direction solar panels face is important because the amount of light energy they absorb depends on the position of the sun in the sky. This varies across the seasons.
A solar panel system functions optimally when it’s exposed to as much direct sunlight as possible – when the sun’s rays strike the panels at a perpendicular angle (a direct path of 90 degrees). This is why solar panels save you most on energy bills during summer. Output peaks with the higher sun angles and longer daylight hours.
Because the UK is in the northern hemisphere, our solar panels produce around 70 percent of their total output from March to August – our spring and summer. The remaining 30 percent is generated from September to February – autumn to winter.
Alternatives To Dual-Axis Solar Panels
If solar panels on the two sides of your roof may not be the best solution, there are a few other solar systems you can consider.
Ground-Mounted Solar Panels
Installing solar panels at ground level is an option provided your property has enough land space.
Ground-mounted solar panels are fixed to a frame or pole that raises them above the ground from a few inches to several feet. They enable more control over panel direction and angle to ensure they receive as much sunlight as possible.
Solar panels at ground level typically cost more to install than rooftop solar panels but cleaning, maintenance and repair is easier.
Wall-Mounted Solar Panels
Wall-mounted solar panels can be less efficient than a rooftop system and cost more but they’re another option that allows you to go solar if your roof isn’t suitable.
Like rooftop solar panels, wall-mounted systems work best when they face south. They may last longer than rooftop panels because they tend to be less exposed to harsh weather conditions.
As far as aesthetics are concerned, wall-mounted solar panels have greater impact than rooftop panels because they’re more visible, so that’s something to keep in mind.
Bifacial Solar Panels
Bifacial (dual-sided) solar panels produce around 30 percent more power than standard, monofacial (single-sided) systems.
With solar cells on both sides of the panel, they’re designed with new solar technology that addresses the problem of efficiency losses with regular solar panels. And they perform better in indirect light.
Double-sided solar panels are preferred by some businesses and in some cases could also be a residential alternative to solar panels on both sides of the roof.
Bifacial solar panels cost more than standard solar panels but are generally more durable and may last longer.
Final Thoughts On Solar Panels On Each Side Of Roof
If solar panels on one side of your roof won’t give you enough electricity, panels on both sides may be the answer.
These dual-axis solar systems, facing both east and west, are more expensive but provide optimal power output.
If you’d like to find out more about installing solar panels on both sides of a roof, we can help. Get in touch with Effective Home online or call 0333 003 0703.
