North-facing vs south-facing panels

One of the first things you learn when you start researching solar panels is that south-facing ones are best - at least in the northern hemisphere. 

This still holds true, but solar photovoltaic (PV) technology has improved significantly over the past 20 years, which has opened the door for panels facing in any direction. 

In this guide, we’ll compare north-facing solar panels with south-facing ones, take a look at a real-world example, and consider whether it’s actually worth having a solar panel system that looks north. 

Regardless of what direction your roof faces, if you’re wondering how much a solar & battery system could save you, answer a few quick questions below and we’ll provide you with an estimate.

Are south-facing solar panels the best?

When it comes to solar panel orientation, the proven advice in the northern half of the globe is to install your panels facing south in order to capture the most light, and therefore generate the most power.

The science behind this recommendation comes from solar geometry and the Earth's position relative to the equator (otherwise known as its axial tilt). In the northern hemisphere, the sun is always slightly to the south, regardless of the time of year.

The tilt angle of solar panels also plays a crucial role here. Ideally, an installation should match the latitude of its location to ensure that sunlight strikes the surface of the panels as directly as possible all year round.

Generally speaking, in the UK, solar panels work best at about a 40-degree angle from horizontal. This setup improves the panels' daylight exposure, especially during the lower winter sun.

However, this principle flips when you cross the equator. In the southern hemisphere, the sun’s path is predominantly to the north, making north-facing solar panels the ideal choice over there.

Solar panel output based on orientation

The above chart shows the impact of different orientations on solar panel output, based on a 2019 study by the University of York. 

The various orientations are measured in terms of ‘degrees from the south’ - so a perfectly south-facing array is at zero degrees, while an east-facing array is at -90 degrees, and a west-facing array is at 90 degrees.

The study examined the performance of 26 Yorkshire-based solar PV arrays (each with a four kilowatt-peak (kWp) power rating) to assess how orientation affects performance.

While south-facing arrays yielded the highest output, east- and west-facing arrays also performed well, according to the findings. However, the difference in output between east- and west-facing systems is relatively small in percentage terms.

This means that while south-facing is optimal, east- and west-facing panels can still generate significant amounts of electricity, making them viable alternatives when south-facing roofs aren’t available.

Do north-facing solar panels work?

As noted earlier, north-facing solar panels in the northern hemisphere get less direct light throughout the day because the sun is slightly to the south. Despite this, they're still capable of generating a sizeable output.

On average, solar panels facing true north are about 54% as effective as panels facing true south (more details in the next section).

While output is clearly lower, it's by no means trivial - and turning the panels northwest or northeast, rather than directly north, boosts generation by better capturing morning and afternoon sunlight.

We’re certainly no strangers to north-facing arrays at Sunsave. In December 2023, we installed a north-east-facing system in Hampshire for one of our customers, Richard, which performs impressively despite its orientation.

A real-life comparison

A fantastic real-world example of north-facing vs south-facing solar panels comes from Oval Renewables, a solar installer based in York, who documented their findings in a couple of comprehensive YouTube videos.

They installed two solar PV arrays on a rooftop in Cramlington, near Newcastle - one facing true south and the other facing true north. Both arrays consisted of 12 panels rated at 375 watts (W) each and were free from shading issues.

The system produced a total of 7,014 kilowatt-hours (kWh) of electricity in its first year (April 2023 - April 2024), with the south-facing array generating 4,556kWh, and the north-facing array generating 2,457kWh.

This means the north-facing panels achieved 54% of the output of the south-facing panels - far more than many would expect. And even more impressively, the electricity generated by the north-facing panels made up 35% of the year’s total.

This shows that while south-facing panels are more effective, north-facing panels can still contribute significantly to overall electricity production.

At Sunsave, our solar specialists consider every aspect of your roof when designing your system and, if necessary, we'll suggest putting panels on the north side.

To find out how much you could save with a solar & battery system, simply answer a few quick questions below, and we’ll give you an estimate.

Why do north-facing solar panels work so effectively?

The reason north-facing solar panels can still generate electricity is because they don’t rely on direct light. PV cells certainly perform the best under direct light, but they also harness indirect (or ambient) light, which is present all year round.

Indirect light is essentially solar radiation that has been scattered in all directions by particles in the atmosphere and clouds, or reflected off surfaces like buildings, water, or the ground.

This scattered light reaches the Earth’s surface and can be absorbed by solar panels. While it’s weaker than direct sunlight, it still provides enough energy to make solar panels work.

On bright days (and especially during the summer months), there’s plenty of ambient light. For north-facing panels, this means they can capture indirect light throughout the day, even without direct exposure to the sun.

Why has north-facing solar panel output improved?

The amount of light hitting north-facing roofs obviously hasn’t changed, but the technology of solar panels has improved dramatically. Modern solar panels are significantly more powerful and efficient than those from 15-20 years ago, producing more electricity even in low-light conditions.

For example, according to Wood Mackenzie, the average power rating of a residential solar panel in the 2010s was around 290W. Many of today's panels exceed 500W, which can generate significantly more electricity under the same conditions - and for a fraction of the cost.

To learn more, check out our rundown of the most powerful solar panels.

A 2010 report from the National Renewable Energy Laboratory (NREL) showed that the average efficiency of monocrystalline solar panels was around 14%. Now, the latest panels boast efficiencies of 20-25%, meaning they can convert a much higher percentage of daylight into usable electricity.

You can find out more in our guide to the most efficient solar panels.

Is it worth getting north-facing solar panels?

On their own, solar panels facing true north aren't likely to be worth it. Their lower output compared to east-, west- and south-facing panels means they probably won’t justify the initial cost.

However, as part of a larger solar installation that includes panels facing other directions, north-facing panels are usually well worth it.

Once you’re already paying the fixed costs of a solar installation (including labour and  scaffolding), adding a few extra panels to the north-facing side of your roof usually won’t increase the total price by much.

Those additional panels will contribute a decent chunk to your system’s annual electricity output, and a larger system size will help lower your electricity bills even further.

If you’re shopping around for solar panel quotes, it’s always worth asking your installer to include north-facing panels in your design so you can see how the additional panels impact both the cost and the expected savings.

Wondering how much a solar & battery system could save you? Click the button below, provide a few quick details, and we’ll provide you with an estimate.

North-facing solar panels: FAQs