North vs West Facing Solar Panels: Which Wins?

Ask ten Australians about solar panel direction and nine will tell you the same thing: face them north. That advice isn't wrong, but it's incomplete — and it was written for an era when feed-in tariffs were generous and exporting power was almost as good as using it.

Today the maths has shifted. What matters is not just how much electricity your system makes, but when it makes it and whether you're home to use it. That's where west-facing panels enter the conversation.

Why north is the default answer

Australia sits in the southern hemisphere, so the sun tracks across the northern half of the sky. A roof plane facing true north (not magnetic north — there's a difference of several degrees depending on your state) catches sunlight most squarely through the middle of the day and across the year.

The practical result:

• Highest total annual output per kW installed of any orientation.
• Most consistent winter performance, when the sun sits low and northern exposure matters most.
• A smooth production curve that peaks around solar noon.

If your only goal is to generate the maximum number of kWh from a fixed number of panels, north wins. That's why installers default to it and why almost every rule of thumb starts there.

The catch with a north-only system

A north-facing array does its best work between roughly 10am and 2pm. If nobody's home, that generation goes out to the grid as an export.

Exporting isn't worthless, but across most of Australia the value of a kWh you export is now well below the value of a kWh you avoid buying. Retail electricity rates and feed-in tariffs have moved in opposite directions for years, and some retailers have introduced time-based export rates that pay very little during the middle of the day precisely because so much solar is being dumped into the grid at once.

So a big midday peak can be a slightly awkward asset. Your meter spins backwards at the cheapest possible time, then forwards again at the most expensive.

What west-facing panels actually do

West-facing panels start slowly and finish strong. Their output ramps up through the afternoon and holds later into the evening than a north array, shifting the production curve to the right.

That matters because household demand in most Australian homes is shaped like a camel with two humps: a small morning peak, a midday dip, and a big late-afternoon-to-evening peak when people get home, the air conditioner goes on, the oven fires up and everyone plugs in a device.

West-facing solar lines up much better with that evening hump. You'll produce fewer total kWh over the year — typically a modest reduction compared with a well-oriented north array, depending on your latitude and roof pitch — but a higher share of those kWh get consumed on site instead of exported.

	North-facing	West-facing	East-facing
Total annual output	Highest	Slightly lower	Slightly lower
Peak production time	Middle of the day	Afternoon / early evening	Morning
Suits households who are	Home during the day, or have a battery	Out during the day, home by late afternoon	Early risers, morning-heavy usage
Winter performance	Strongest	Weaker (shorter afternoons)	Weaker
Summer afternoon aircon match	Moderate	Excellent	Poor

East is west's mirror image. It's genuinely useful if your household runs hot in the morning — hot water, a home office that starts at 7am, kids' showers and breakfast — but it fades exactly when most families ramp up.

So which one should you choose?

The honest answer is that it depends on four things, and only one of them is your roof.

1. When you actually use power

Pull up your last few electricity bills. If your retailer gives you interval or half-hourly data (many do, via an online portal), look at the shape of your day rather than just the total.

• Heavy daytime usage — retirees, shift workers, people working from home full-time, pool pumps running midday, ducted air conditioning through summer days. North is a strong fit.
• Empty house 8am to 5pm, then a big evening — the classic two-income household. West-leaning panels will convert more of your generation into actual savings.

2. Your feed-in tariff and tariff structure

The gap between what you pay per kWh and what you're credited per kWh for exports drives everything. The wider that gap, the more valuable self-consumption becomes, and the more attractive a west orientation looks.

If you're on a time-of-use tariff with an expensive late-afternoon peak window, west-facing panels can shave the top off exactly the hours you're being charged the most. Rates vary by state, retailer and plan, so check your own bill rather than relying on a national average — and note that these numbers change, sometimes annually.

3. Whether a battery is in the picture

A battery changes the argument substantially. Once you can store midday surplus and release it at 6pm, the timing advantage of west-facing panels largely disappears. What matters then is raw generation — filling that battery as fully and as early as possible, which favours north.

So a rough guide:

• No battery, none planned → orientation timing matters a lot. Consider west or a north-west split.
• Battery now, or likely within a few years → maximise total output. Lean north, and size the array with the battery in mind.

4. What your roof actually offers

All of this is academic if you only have one usable roof plane. Plenty of Australian homes — especially in newer estates with narrow blocks and complex rooflines — have limited unshaded space, and the real constraint is fitting panels at all.

Also worth checking:

• Shading from trees, neighbouring buildings, chimneys and vent pipes. Afternoon shade from a western neighbour can wipe out the entire benefit of a west array.
• Roof pitch. A steeper pitch exaggerates orientation effects; a nearly flat roof flattens the difference between north, east and west considerably.
• Structural and access issues on tile versus metal roofs, and enough space around panels for compliant installation.

The split-array option most homes end up with

In practice, a lot of well-designed Australian systems don't pick a side. They split panels across two or even three roof planes — commonly north and west, sometimes east and west.

The benefits of a split array:

• A broader, flatter generation curve that starts earlier and finishes later, covering more of your household's real demand.
• Less midday export spill, which matters if your network has an export limit on your connection.
• Better use of awkward roofs, letting you install more total capacity than a single plane allows.

The trade-offs are worth knowing. A split array needs the inverter set up correctly — usually separate MPPT inputs for each string, or microinverters or optimisers where planes differ a lot. It can add a little to labour and hardware. And a poorly configured split, where mismatched strings share one input, will underperform both options.

This is exactly the kind of decision where a site-specific design beats a rule of thumb. A good installer will model your actual roof planes, pitch, shading and postcode-specific solar data, then show you the expected output profile for a couple of layout options.

Practical steps before you commit

1. Find your usage shape. Log into your retailer's portal and look for interval data or a daily usage graph. Note your heaviest hours.
2. Check your export credit versus your import rate. Both are on your bill. The bigger the difference, the more you should value self-consumption.
3. Walk your roof planes (from the ground) at 9am, midday and 4pm on a clear day. Note where shadows fall.
4. Decide on batteries in principle, even if not now. It changes the ideal design.
5. Ask every quote for a production profile, not just an annual kWh figure. You want to see the hourly shape.
6. Compare at least three designs. Two installers looking at the same roof will often propose different orientations — and their reasoning tells you a lot about their quality.

Frequently asked questions

Do west-facing panels produce much less than north?

Less, but not dramatically so for most Australian roofs. The reduction depends on your latitude and roof pitch — a shallow pitch in northern Australia narrows the gap considerably, while a steep pitch in Tasmania or Victoria widens it. The more useful question is how much of that output you'll consume yourself, because a smaller number of self-consumed kWh can be worth more than a larger number of exported kWh.

Should I add west-facing panels to an existing north-facing system?

Often yes, if you have unshaded roof space and your evening bills are still high. The main things to check are your inverter's spare capacity and input configuration, your network's export limit, and whether modifying the system affects any existing arrangements with your retailer. An installer can assess whether an add-on makes sense or whether a larger replacement inverter is the better path.

Does panel orientation affect STC eligibility?

Small-scale technology certificates are calculated on system capacity and your postcode zone rather than the compass direction of your panels. Orientation affects how much electricity you actually generate, not the certificate calculation itself. The number of STCs available also steps down over time, so the value built into a quote changes year to year.

What about south-facing panels?

South is the weakest orientation in Australia and usually a last resort. It can still make sense on very shallow-pitched roofs, or where it's the only way to add meaningful capacity to a system, but expect noticeably lower annual output — and be sceptical of any quote that puts a large share of your panels facing south without a clear explanation.

Get a design based on your actual roof

Orientation is one of the few solar decisions you can't easily change later, and it's worth getting right the first time. The best way to settle north versus west is to have SAA-accredited installers look at your specific roof, shading and usage pattern and model the options side by side.

Get your free solar quote and compare designs from accredited local installers — no cost, no obligation, and no guessing which way to point your panels.