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Solar Troubleshooting

Your bill went up after solar? Here is what is really going on.

It is one of the most common — and most frustrating — surprises after going solar. The honest news: it is usually not a faulty system. It is three things sellers rarely spell out, plus a few clear signs of when something genuinely is wrong. Here is how to tell the difference.

Reviewed by Josh, Mission Green Energy Team · Updated July 2026

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Why did my bill go up
after getting solar?

In most cases it is not a broken system — it is three things the sales pitch tends to skip: the fixed daily supply charge, feed-in tariffs that have fallen sharply, and when you actually use your power. The fix is usually behaviour, not buying more panels.

The daily supply charge
you pay no matter what.

Every grid-connected home pays a fixed daily charge just to stay connected — regardless of how much power it draws. Solar doesn't remove it, and on a low-usage bill it can quietly become the biggest line item.

Feed-in tariffs have
fallen sharply.

The credit you earn for exporting surplus solar has dropped a lot across Australia. Exporting is no longer where the money is — self-consuming your own solar is. This one shift changes the whole strategy.

When you use power
matters as much as how much.

Solar only offsets what you use while the sun is up. Run the big loads at night on grid power and your panels never touch them — which is why two identical systems can produce wildly different bills.

How do I tell if my system
is genuinely underperforming?

Usually the bill is explained by the three causes above. But sometimes a system really is underperforming — and there are a few clear, safe signs you can check yourself before calling anyone out.

Check

Generation far below expectation

On a clear, sunny day, your system should be producing close to its expected output around the middle of the day. If your app or inverter shows generation far below what a bright day should give, that is worth investigating — compare it to how it performed when the system was new.

Check

A fault light or error code

A red or amber warning light on the inverter, or an error code on its screen or app, is a genuine signal something needs attention. Note the exact code — do not open the unit — and check it against your inverter manual or the manufacturer's support page.

Check

Zero export when the sun is out

If your monitoring shows no generation or no export at all in the middle of a sunny day while you are using little power, the system may not be feeding in at all. Our guide to solar that stopped exporting to the grid covers this exact symptom.

Checking safely —
what to do and what never to touch.

Reading your app and comparing output is completely safe. Anything involving wiring, the roof, or opening equipment is not — that is licensed-electrician territory, always.

So — what should you actually do?

Here is the advice we would give a friend: rule out a fault with a two-minute app check, then attack the bill with behaviour before you spend a cent on hardware.

Still stumped by your bill? Get a free, no-obligation assessment and we'll read your real usage and tell you honestly whether it's behaviour, your plan, or a genuine fault — and whether spending anything is even worth it. See our public honesty record for how often our advice is simply "you don't need to buy anything".
Get a Free, Honest Assessment →

Bill went up after solar?
Your questions, answered.

In most cases it is not a faulty system — it is three things sellers rarely spell out. First, you still pay a fixed daily supply charge just to stay connected to the grid, every single day, even if your panels cover all your usage. Second, feed-in tariffs (the credit you get for exporting surplus solar) have fallen sharply, so exporting earns far less than it used to — the value is now in using your own solar, not selling it. Third, timing and behaviour: if you run big loads like heating, cooling, the dryer or the dishwasher at night on grid power, your panels never offset them. Add a general rise in electricity prices and a hot or cold quarter, and a bill can rise even with solar working perfectly. The fix is usually behaviour and self-consumption, not buying more panels. Occasionally the system genuinely is underperforming — this page shows you how to check that safely.

The daily supply charge (sometimes called the service-to-property or fixed charge) is a set amount your retailer bills every day just to keep you connected to the grid, regardless of how much power you use. It is charged even on days your solar covers all your usage, and it does not disappear when you install solar. Because it is fixed, it can make up a large slice of a low-usage bill, so a household that has cut its usage right down with solar can be surprised to see the supply charge now dominates the bill. The only ways to remove it entirely are to go fully off-grid (rarely worth it for most homes) or to disconnect from the grid, which most households do not want to do for reliability reasons. It is a normal, unavoidable part of a grid-connected bill, not a sign anything is wrong with your solar.

Feed-in tariffs — the per-kilowatt-hour credit you earn for exporting surplus solar to the grid — have fallen sharply across Australia as more rooftop solar has come online. So much cheap solar floods the grid in the middle of the day that the wholesale value of that midday energy has dropped, and retailers have cut their feed-in rates to match. Many households who signed up years ago on a generous rate now find their new or renewed plan pays a fraction of what it once did. This is why the strategy has flipped: the real value of solar is no longer selling your surplus, it is self-consuming it — using your own solar to run appliances during the day so you buy less expensive grid power, and in some states considering a battery to shift that surplus into the evening. It is a market shift, not a fault in your system.

The single biggest lever is self-consumption — using more of your solar while the sun is up instead of exporting it for a low feed-in tariff. Run the big loads in daylight: put the dishwasher, washing machine and dryer on a daytime timer, pre-heat or pre-cool the house in the afternoon, and charge an EV or heat your hot water during the day rather than overnight on grid power. Every kilowatt-hour you use from your own panels is one you do not buy at the full grid rate, which is worth far more than the small feed-in credit you would have earned exporting it. Beyond behaviour, check you are on a plan that suits a solar home, and if you have real evening and overnight usage, look honestly at whether a battery pays back within its warranty life on your numbers — not just because a salesperson says so. A free Mission Green assessment can run your actual usage and tell you which of these moves is worth it for your home.

Start by checking your inverter or monitoring app on a clear, sunny day. A healthy system should be generating close to its expected output around the middle of the day, and you should see energy being exported when you are using little at home. Warning signs of a genuine fault include: generation that is far below what you would expect on a bright day, a red or amber fault light or an error code on the inverter, or zero export showing on your app or meter when the sun is out and you are not using much power. If you see any of these, do not open the equipment or touch any wiring yourself — note the reading or error code, and if the manual describes a simple restart via the inverter's isolator switch you can try that only if it is safe and straightforward. For anything beyond a basic reset, or if the fault light stays on, call your installer or a CEC-accredited service to inspect it. Often, though, the system is fine and the bill is explained by the supply charge, a low feed-in tariff, or usage timing.

Not automatically — a battery is sometimes the right answer and sometimes an expensive one that will not pay for itself, so the honest advice is to check your numbers first. A battery helps most when you have real evening and overnight usage, a high peak import rate, a low feed-in tariff (so exporting earns little), and daytime solar surplus you are currently giving away cheaply. It helps far less if you are out all day and use little at home after dark, or still have a generous feed-in tariff. It also does nothing to remove the fixed daily supply charge. Before spending on a battery, make sure you are already self-consuming as much solar as you can through behaviour, since that is free. If the numbers genuinely stack up, a battery can be worth it — but a free assessment is the honest way to tell, and we would rather say wait or buy smaller than sell you one that does not pay.

Make sense of your energy bill.

Book a free energy assessment and we'll read your real usage — telling you honestly whether it's behaviour, your plan, or a genuine fault, and what's actually worth doing about it.

Book Free Assessment →