Solar Panel Direction: Which way should my solar panels be facing?
Five or six years ago the question of which direction solar panels should face was easy. Because high feed-in tariffs were available, they simply had to have an orientation facing north in order to maximise the amount of electricity they produced and so earn the most feed-in tariff money possible.
But now high feed-in tariffs are a thing of the past, so the question of orientation is more complicated because of the importance of maximising self consumption, which is making sure your home uses the most solar electricity and the least grid electricity possible. The concept of self consumption is the key to tiny electricity bills with solar panels – if you don’t know why, read this and then come back.
Using your own solar electricity instead of grid power is far more cost effective than receiving a low feed-in tariff for sending electricity into the grid. The more you are charged for grid electricity and the lower your solar feed-in tariff, the more important it becomes to maximise self consumption.
Which Solar Panel Direction Will Maximise Your Self Consumption?
The best panel direction to maximise self consumption of solar electricity will depend upon a household’s electricity usage patterns. Panel directions and the type of households various orientations generally best suit are given below:
North Orientation: Panels that face north will produce the most electricity overall. North facing solar panels are often the best choice for people who are at home during the day. Not only because they are there to use electricity when it is produced, but also because it is easy for them to shift demand by using washing machines, clothes dryers, pool filters and other devices in the middle of the day. Because north facing solar panels produce the most electricity overall, they will have the greatest environmental benefit.
West Orientation: Panels facing west produce around 15% less electricity overall than north facing solar panels. They also produce less electricity in the morning but more in the afternoon. They reach their maximum output around one and a half hours after noon and just before sunset will produce around one quarter of their peak maximum. West can be a good direction for people with high summer air conditioning demand. It is also an excellent direction for people who are usually out of the house by the time the sun comes up but return in the afternoon. However, because of the reduction in the total amount of electricity generated compared to north facing panels, the increase in self consumption that will result will need to be considerable to make west facing solar panels worthwhile.
North-West Orientation: Solar panels that face north-west will produce around 5% less electricity overall than north facing panels. Their electricity production through the day will be between that of north and facing panels and that of west facing panels. They produce slightly more electricity during the afternoon and slightly less in the morning.
East Orientation: Solar modules that face east are similar to west facing panels in producing around 15% less electricity overall than north facing ones, but they will produce more electricity in the morning and less in the afternoon. They can suit households with high consumption in the morning, such as ones that use a lot of electric heating on cold winter mornings or people who are out of the house in the afternoon.
North-east Orientation: Panels facing north-east provide will produce around 5% less electricity than north facing solar panels and their production through the day will be between that of north facing modules and east facing ones.
East And West Orientation: Placing some solar panels facing east and some facing west will result in the total amount of electricity produced being around 15% less than if all the modules were placed facing north. This arrangement is often called and east/west split and has the advantage of producing a more constant output of electricity during the day which can help to increase self consumption. The steeper the roof, the smoother the output of the system will be.
An east/west split can normally have a different number of modules facing in each direction. So if a household uses more electricity in the afternoon more solar panels can be installed facing west.
An east/west split can suit both people who are home through the day and those who are at home in the morning and the afternoon.
South Orientation: For most Australians, south is the worst direction modules can face and some people consider installing panels facing south almost as large a mistake as installing them upside down. But given the huge decrease in the cost of solar panels over the past ten years, installing solar panels on a south-facing roof is worth it nowadays.
In Sydney south facing solar panels will typically produce around 28% less energy than north facing panels and the steeper the roof the less electricity they will produce.
But in the far north the difference is not so great and in Townsville south facing solar panels will only produce around 17% less electricity in total than north facing ones. In addition, they will produce more electricity in summer than north facing panels. Because people in Townsville use usually use considerably more electricity in summer than winter as they run their air conditioners, south facing modules can improve self consumption there.
In Darwin south facing panels only produce about 15% less electricity overall than north facing panels, but the most cost effective direction to face solar modules is north.
Combining Directions: Panels can be placed in multiple directions other than just an east/west split. For example, some solar panels could be placed facing north and some facing west. This will result in an output similar to north-west facing panels. It is even possible to have solar panels facing in more than two directions.
Best Solar Panel Direction In Each Capital City
Clicking on one of the Australian capital cities below will display a compass image showing the optimum panel orientation for that city.
Power Loss Table: This table shows you how much energy you can expect to get from almost any combination of solar panel direction and angle in the capital cities, compared to the ‘optimum’ orientation. For example, in Brisbane if your panels are facing West (270°) and are angled 20° from horizontal you will get 89% of the energy compared to the optimum orentation of North and 30°.
Panel Direction And Solar Inverters
The type of solar inverter you have will affect how many different directions in which you can place panels. The most common sort in Australia are string inverters. Some can only cope with solar panels facing in one direction, but inverters that can handle two directions are now common.
Microinverters and power optimisers are tiny devices attached to each solar panel. As they make each module independent of the others you can face them in as many different directions as you have panels.
Is my House Suitable for Solar? What we look for when checking a home’s solar suitability in Ireland
That’s a question we get a lot and would be only too happy to help you with.
We look at a lot of factors when deciding if a house is suitable for PV solar panels. One of our most important jobs is to help a homeowner decide if solar is a good idea in the first place.
For a lot of homes in Ireland solar is a great addition, but we do (and have) recommended people against fitting solar where we think it would not be a good investment for their or the environment.
There are 5 main factors to consider when deciding if your home is suitable for solar:
Let us do the hard work
The below is just in case its of interest for you. We are more than happy to check the suitability of your home for solar for you, that’s our job. Its quick, and its free. If you’d like numbers for your own home, including costs and predicted electricity generation numbers, just fill in the solar PV quote form and we’d be glad to help.
Pitched roof types
Solar panels can be fitted on just about any roof type. They work very well with all the main roof types here in Ireland.
Flat concrete tiles, fibre cement slate, pan tile / roman tile / wavy tile and natural slate are the most common types here in Ireland and solar panels can be fitted to any of those. Natural slate takes a little longer than the others, and so the installation process might take half a day longer.
Flat roof types
Solar panels can be fitted to just about any type of flat roof without compromising it’s water tightness. In this case, a frame is added to tilt the panels up to face the sun.
If you have a flat roof then we can point the your solar panels any direction, which normally will be south.
If you have a pitched roof though the direction the panels will face depends on which direction your roof is already pointing (as you cannot put frames onto pitched roofs to point the panels in a different direction).
Due South: most power output
A south facing roof will produce the most electricity. Being a bit off directly south though has minimal impact on production. Anywhere between south-east and south-west will be very similar.
South East / South West: 5% Lower
If your roof faces south-east, or south-west, then your production will be a little lower. The timing of your electricity production will change too. South east produces more in the morning, and south west more in the afternoon / evening.
East / West: 20% Lower, but more useful?
If your roof faces due east, or due west, the production will be about 20% lower than a south facing roof.
The production numbers though are still very good and make a savvy financial investment. There’s a side benefit to east / west facing solar arrays, as they produce the most electricity when you need it most.
Most homes use their largest amount of electricity in the morning (when east facing panels are producing), and late/afternoon evening (when west facing panels are producing), as people turn on their kettles, showers and ovens.
There’s a good argument for east / west facing arrays as it means less need for battery storage as you can use the power directly. You could also cover both sides of your roof as both are pointing in a useful direction.
Northerly: not worthwhile in Ireland
As you move to pointing north the production from solar panels rapidly drops off, and we would not recommend it as a good financial or carbon-footprint reducing investment.
Azimuth, the technical term for direction
In solar calculation reports you’ll see the term azimuth, normally quoted in degrees. That’s just the fancy term for which direction the panels will be facing.
Is my roof big enough for solar?
Very likely is the short answer. Most Irish houses have ample space on their rooves to make electric solar panels worthwhile.
For example, a typical 2 bed mid-terrace house might have enough space to fit a 3kW solar panel array on it’s roof, which is big enough to produce almost half the electricity that family might use in the year.
Here’s a ball park guide to the amount of power that common roof areas would produce:
|15m 2 typical 2 bed mid terrace||3.15kWp||2709kWh|
|20m 2 typical 3 bed semi-detached||4.2kWp||3612kWh|
|25m 2 typical 4 bed stand alone||5.25kWp||4515kWh|
The above numbers are the area covered in panels. Due to planning permission rules here in Ireland you cannot fill the whole face of the roof. You need to leave a margin free from panels:
- Top of roof (by the ridgeline): 0.25m left free
- Bottom of roof: 0.5m left free
- Sides of roof: 0.5m left free if end of roof, no free space required if mid-terrace.
If you are doing your own back-of-envelope numbers do keep in mind your roof is on an angle, so it has more area that a flat roof would. A typical home in Ireland has a 30° slope on it’s roof, so giving you 15% more area to fill with solar panels than a flat roof on the same building.
My roof has lots of angles
It would depend in that case. Lots of small triangles can be difficult, as solar panels are rectangular. Often though it can be fine with a bit of planning in both solar panel positioning and inverter design.
Unsure about your roof and solar? Just ask.
If you are not sure if your roof would be suitable please do feel free to fill in our solar panel quote form. We can quickly have a look at your roof on google maps and let you know what might be possible. It’s quick and entirely free. We would give you quick quote including guide numbers to both costs and projects solar generation figures to help you decide if solar PV is the right choice for your home.
Shading Solar Panels
Shading can be an issue, and should be taken into account before deciding is solar is a good idea, both for your and for the environment.
Neighbouring buildings and trees
If your roof spends a lot of time in direct shadow then solar might not be the best choice. A bit of shadow early or late in the day is not really an issue, but direct shadow for significant parts of the middle of the day would be.
You do not need to be able to see the horizon from your roof. As long as you can see most of the sky it is normally fine.
If it helps, the sun hits a bit over 60° in the sky during mid summer in Ireland, whereas mid winter it’s nearer 15° on the shortest day.
Chimneys and dormer Windows
One item creating a shadow tracking across your panels is not usually an issue. With a bit of planning in how the panels are wired up and inverter planning then we can mitigate for such.
If your roof has many items causing lots of shadows that can affect the production. Let’s say you’ve a large chimney breast in the middle of your roof plus two dormer Windows, with just small gaps in between. In that case its possible that the gaps are in shadow too much of the time to be worth putting panels in there.
Really though, to know for sure we’d need to take a quick look. The direction your roof faces is another important factor in looking at shadows.
Unsure about shading on your house? Just ask.
Again if you are unsure please don’t hesitate to ask. We can have a quick look to see if shading would be an issue or not for you. We can see a lot just from google maps, and also we have drones so we can check for shading issues from a roof-height perspective. Just get in touch if you’d like to chat more on this.
We will always be straight on this. If we think solar would not make economic sense for you due to solar, we wil always tell you that.
When our engineers do the site inspection before giving you your finalised quote, they will check your fuse board and electrics. This is required, as well as being a very good idea too!
Modern fuse boards very rarely need any work. The only issues we see are on particularly old electrics and it’s usually around missing earth bonding or another issue with the earth.
If we see any problems like that, we’ll let you know and it might be something you have to get rectified before solar panels can be added to your home.
This is only a good thing for your home though. It is highlighting places where safety has fallen behind modern standards and usually the improvements are relatively easy to do.
A solar immersion diverter is an optional extra that takes an spare power not required by your house and uses it to heat your water tank via your immersion element.
If you would like that you need to have a hot water tank that has an immersion element in it. You do not need to have a separate, extra immersion element just for solar. The one element can be used by solar and you can turn it on manually just like before whenever you like too.
If you have a hot water tank that does not have an immersion element, you can add a device called a Willis heater. Effectively this adds a immersion heater outside your tank that circulates the hot water into your tank. very clever!
They are relatively cheap, and you’d need a plumber to install it before we wire it up. Just get in touch if you’d like to know more about them.
A better use of spare power?
There is no need to feel compelled to add an immersion diverter to save wasting power any more. From 2022 you get paid for any unused electricity your panels generate that gets sent back to the grid, which is a great use of spare electricity you make.
Your house will almost definitely be eligible for the SEAI Solar Electricity grant as long as:
- You have a connection to the grid
- It was build an occupied by 31st Dec 2020
- This grant has not been claimed before on that property
They are the main requirements that depend on your property, though you can see our page about SEAI grants for solar for more info, or see the SEAI’s Website.
Ireland’s Solar Feed-in Tariff
From 15th Feb 2022, you can sell your excess solar electricity back to the grid and get paid for every unit. They call this the Clean Export Guarantee (CEG) tariff. Read more.
Solar Grants Guide
A step-by-step guide to solar grants. How much are they, how to apply, planning permission, etc. Read more.
We’re an independent Irish solar panel installation company with bases in Galway and Dublin. We are a solar PV installer across Ireland. Solar is in our DNA, and we’re on a mission to see solar panels installed on every roof in Ireland. That way, we can all save money and look after this little planet we all call home. If you have any questions about going solar, please just get in touch – we love to talk!
PureVolt Solar Services
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Solar panel orientation
The placement and orientation of solar panels is just as important as which type of solar panel is used in a given situation. A solar panel will harness the most power when the Sun’s rays hit its surface perpendicularly.  Ensuring that solar panels face the correct direction and have an appropriate tilt will help ensure that they produce maximum energy as they are exposed to the highest intensity of sunlight for the greatest period of time.  Some solar arrays follow the Sun using solar tracking systems which significantly increase energy production. The following sections refer only to ‘fixed’ or non-tracking systems.
In the northern hemisphere, the general rule for solar panel placement is, solar panels should face true south (and in the southern, true north). Usually this is the best direction because solar panels will receive direct light throughout the day. However there is a difference between magnetic south and true south that must be considered. Magnetic south is the south shown when a compass is used, and this south points to the Earth’s south magnetic pole. Solar panels, however, need to face solar or geographic south, which is the direction towards the South Pole.  By the same reasoning, if the solar panel is located in the southern hemisphere, the panel should instead face in the direction of true north.
Depending on how solar panels are being used, it may also be beneficial to have a slight rotation away from due south. For example, depending on the use solar panels used for a home should face slightly south-west. These panels collect more energy when they face due south, but the energy is more useful if it comes later in the day. This turn allows the solar panels to produce more electricity at the hours when it is needed. Pointing the panels slightly south-west, in the direction of the setting Sun, would allow the panels to produce more energy in the evening, when people are home and using more appliances. The decrease in total production is balanced by the electricity available when it is needed most. In most areas there is enough electricity available from other sources in the morning and midday. 
When solar collectors are used for heating and lighting specifically. particularly in the form of fenestration such as Windows. it is actually best to have these collectors facing somewhat east. Warming the house for the day means morning sunlight is needed most. 
The angle or tilt of a solar panel is also an important consideration. The angle that a solar panel should be set at to produce the most energy in a given year is determined by the geographical latitude. A general rule for optimal annual energy production is to set the solar panel tilt angle equal to the geographical latitude.  For example, if the location of the solar array is at 50 o latitude, the optimal tilt angle is also 50 o. Essentially, the closer a solar panel is located to the equator the more the panel should be pointing straight up. The closer the panel is to the poles, the more they should tilt towards the equator. 
The angle of solar panels can also influence the power output due to climatic and environmental factors. In northern climates, snow accumulation on low-tilt panels can reduce or completely block the Sun’s rays from reaching the solar panel during the winter months. Although this effect will vary for every location, one study in Edmonton, Alberta, Canada concluded that the annual energy loss due to snow accumulation ranges from 1.6% at optimal tilt (53 o ) to 5.3% at low tilt (15 o ).  Additionally, low-tilt solar panels are more susceptible to soiling by dirt and debris which can also partially block the Sun’s rays.
For further reading
For further information please see the related pages below:
What’s the best direction and angle for my solar panels?
Many people are under the misconception that they can’t install solar panels on their roof for a variety of reasons, whether because of the material, their location, shade, or the dimensions of their roof. There are many factors that make a roof more or less suitable for solar, but while some roof qualities make a rooftop solar system installation difficult, others have a minimal impact on solar energy production.
In this article, we’ll review the two main roof factors that impact the performance of solar panels: direction and angle.
Solar panel direction
The direction that your roof faces is one of the primary factors that determine how much sunshine your solar panels will see over the course of the day. True south and true north face the Earth’s axis rather than aligning with Earth’s magnetic poles. For those north of the Equator, the best direction for solar panels is south, while homes in the southern hemisphere would position solar panels on roofs with a northern facing orientation. By positioning solar panels according to true south and the azimuth angle—the angle of the sun in relation to true north and true south—you’ll be able to get the best direction for solar panels and arrays.
Pro tip: Not sure which direction your roof faces? Look your address up on Google Maps! Their grid shows which direction is true south – compare that to your roof’s direction on satellite imagery.
Optimizing your solar panel direction
Generally, solar panels that face directly east or directly west produce about 20 percent less electricity than if they were facing south. This doesn’t mean you won’t save money, but if you’re aiming to cover all of your electricity usage with solar, you may have to install a few more panels than you would otherwise need with a southern-facing system.
Solar panel angle
Solar panel angle refers to the vertical tilt of your solar system. For example, if your solar panels are perpendicular to the ground, they would have a 90-degree angle tilt. In order to collect solar power energy more efficiently, solar panels should be angled to face as close to the sun as possible. Photovoltaics produce power when the angle at which the sun’s rays hit the panel surface (the “angle of incidence”) is small, or when light strikes the panel as close to perpendicular as possible. Therefore, the best angle for your solar panels is the one that allows the panels to get the most direct, perpendicular light.
What factors affect your optimal solar panel angle?
There are a number of factors that will alter the optimal angle of your solar panels. Here are a few things to consider when determining the best tilt for your solar array:
Most solar arrays are installed at an angle that best optimizes sunlight exposure for that location. For the vast majority of U.S. property owners, the ideal angle for a solar panel installation is close or equal to the latitude of your home (on a south-facing roof), somewhere between 30 degrees and 45 degrees. By tilting your solar panels the same angle as the latitude of your home (which means pointing your panels at that average position), you are ensuring that you will get the maximum average output from your solar power system throughout the year.
Best solar panel angle by zip code
Northern vs. southern latitude: New York versus D.C.
To give you an example, we compared data from two places (New York and Washington, D.C.) and estimated the production levels of solar panels tilted at various angles. What we found was consistent with our investigations into the effects of other variables:
Annual electric bill savings (cost of electricity x electricity produced) Assumes an 80% derate factor, 180-degree azimuth, array tilt ~equal to location’s latitude Production ratio (electricity produced/size of system)
Existing roof design
t would be great if everyone had a roof that was angled exactly the same as their latitude, but every property is unique and there is no universal solar panel placement map. Many roofs are going to have slopes between 30 and 40 degrees, which means that solar panels can lie flush against the roof and produce enough electricity for attractive returns.
If you are trying to install solar panels on a steep roof, it may not be possible to place panels at the optimal tilt with traditional racking systems. Because the steep angle of your roof might already be higher than the optimal angle for production, the best you can do is lie your panels flat against the roof. Low-angle roofs will also face obstacles when it comes to solar panel installation and may require specialized racking if you’re looking to tilt them at the optimal angle. Placing panels flush against these types of roofs will mean less electricity production, which will lead to reduced solar savings over time.
In the case of a flat roof, solar installers will usually opt to use racking systems that mount your panels up at an optimal angle. While this allows for your panels to face the sun more directly, you may be limited when it comes to your system size. Tilting panels up on a flat roof will lead to the panels shading one another unless you space and stagger the rows of panels out on the roof. As a result, you can’t install as many panels as you would otherwise be able to if the solar panels were flush against the surface.
Regardless of whether your roof is steep or flat, it’s always best to have a professional solar installer mount the panels on your roof to ensure optimal production and optimal safety. And, if you’re not sure how solar panels could work for your home and roof type, be sure to check out this article to find out if you’re a good fit for solar.
Can’t install solar panels on your roof? Consider community solar.
Time of year
Solar panels work well in the winter, but you will typically see a dip in total energy production during particularly bad winters due to snow covering your panels and reducing their power output. During the winter in the northern hemisphere, the sun is low in relation to the horizon, so one way to counteract winter production dips is to install your panels at a steeper angle than your latitude—somewhere around 60 degrees is optimal. By doing this, you are setting up your panels to perform more efficiently in the winter because they will more directly face the sun as it shines from a lower point in the sky. Plus, installing panels at lower angles can also backfire because snow won’t easily slide off of your array. This will lead to long-lasting snow cover and decreased electricity production.
Another way to decrease seasonal variation in production is to adjust the angle of your solar panels twice a year in the spring and fall. In fact, a system at a 40-degree latitude can see a significant energy boost of about 4 percent. If you’re wondering what the best dates to adjust your solar panel tilt are, we recommend adjusting to the winter angle around September 15th and then adjusting them to the spring and summer angles around March 15th.
What about solar trackers?
The sun’s position is constantly moving throughout the year, and the only way to always have your solar panels angled perfectly is to install a solar tracking system. Solar trackers follow the sun as it moves slightly, which will bump up your energy production. If you are considering a ground-mounted solar system a solar tracking setup may be what you need to optimize your installation.
For the majority of solar shoppers, a rooftop system is the lowest cost and doesn’t take up space on the ground. Solar trackers can’t easily be installed on a rooftop solar system, so they’re generally only used in commercial solar projects – they can dramatically increase production because the tracking system acts as a solar panel angle calculator.
Which matters more: solar panel direction or angle?
While the angle of your solar panels is important, the most important factor in your energy production is the direction your panels face. As previously explained, for the best results, solar panels should be oriented towards the south (assuming you live in the northern hemisphere) because the sun is always in the southern half of the sky in the northern hemisphere.
It’s not a good idea to install your panels to face a suboptimal direction even if it means the best tilt possible. For example, in Boston, a solar array at 30 degrees south is still going to produce more electricity than an array tilted at 42 degrees and facing north.
Common questions about the best angle for solar panels
There are many factors at play when it comes to calculating your solar panel angle, leaving some homeowners a bit confused about what their next steps should be. Check out a few of the most frequently asked questions about optimal solar panel angles and orientation for additional insight.
Calculating the best angle for your solar panels will vary slightly depending on where you live. But, the rule of thumb is that they should be angled to face as close to the sun as possible. As such, the ideal angle for most people is close or equal to the latitude of your home – typically somewhere between 30 degrees and 45 degrees.
The best direction for solar panels is south. This is because the sun is always in the southern half of the sky in the northern hemisphere, and facing south means the most direct sunlight exposure. It’s important to note that it’s not recommended to install your panels to face a suboptimal direction just to get the best tilt possible.
Yes, it is worth tilting your solar panels so that they can collect energy more efficiently. By tilting them, preferably close to the same angle as the latitude of your home, you’ll be able to get the maximum average output from your solar power system year-round.
Neither east nor west is perfect for solar panel orientation, but in both cases, panels can still capture sunlight and generate energy – and savings!
Solar panels don’t need to be south facing but you will get the most output from a south facing system. It’s better for solar panels to face south in the northern hemisphere rather than east or west. North-facing rooftops are the least optimal location for panels.
The best way to find high-quality solar installation is with EnergySage
Determining the ideal solar panel angle for your property is straightforward, but you’ll need a certified professional to recommend equipment and install your solar system. On the EnergySage Marketplace, you can receive free quotes for a solar installation from our qualified, pre-vetted installers across the country who will design and optimize a solar energy system for your unique property. If you are interested in talking to potential installers about the angle of your solar panels, simply leave a note on your profile indicating your interest.
reading on EnergySage
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About Jacob Marsh
Jacob is an EnergySage writer with expertise in solar, electrification, and renewable energy. With over five years of experience researching and writing about the home energy industry (plus a degree in Geological Sciences from Tufts University), he brings a unique scientific approach to writing and investigating all things energy.