How to Read Your Solar Net Billing Bill in Pakistan

If you have solar panels and a green meter, your electricity bill looks different from a normal bill. It has two sets of units instead of one: the units you took from the grid, and the units your panels sent back to it. Many solar owners stare at these two numbers and cannot tell whether they owe money, or whether the company owes them. This guide explains every important line, one by one, in plain English.

First, Find the Two Unit Numbers

Every net billing bill is built on two numbers:

• Import units: the electricity your home took from the grid, usually at night or on cloudy days when your panels were not producing enough.
• Export units: the extra electricity your panels produced during the day and sent back to the grid.

On a green meter these are recorded in separate registers, often labelled as import and export, or as forward and reverse energy. Your bill should show both. If you only see one number, you are probably looking at the wrong section, or your bill is a normal bill and the solar section is printed separately. Compare the two numbers with the readings on your meter itself: the import register and the export register should roughly match what the bill says. A large mismatch is the first sign of a reading error.

How the Bill Combines Them

The bill does not charge you for import units and pay you for export units as two separate bills. It nets them off against each other for the billing period:

• If you imported more than you exported, you pay for the difference, plus the fixed charges and taxes that apply.
• If you exported more than you imported, the extra units become a credit. That credit is normally carried forward to your next bill, where it reduces what you owe. It is not usually paid to you in cash each month.

Under net billing, exported units are credited at a different rate from the rate you pay for imported units, so the credit is not a simple one-for-one swap of units. This is the single most common reason solar owners are surprised by their bill: they expect exported units to cancel imported units exactly, but the two are valued differently. Your bill should show the import charge and the export credit as separate money lines. Check both lines, not just the unit totals. To run your own numbers, see our Net Metering Bill Calculator.

Peak and Off-Peak Lines, When They Apply

Some consumers are on a time-of-use tariff. On such a bill, import units are split into two registers:

• Peak units: electricity used during evening peak hours, charged at the higher peak rate.
• Off-peak units: electricity used during the rest of the day and night, charged at the lower off-peak rate.

This split matters for solar owners because most solar generation happens during the day, in off-peak hours. Your daytime solar output covers your daytime use directly, but it does not erase expensive evening peak imports one for one. If your bill shows no peak and off-peak split, you are on a flat-rate tariff and this section does not apply to you. Do not try to read peak lines into a bill that does not have them. If you are unsure which tariff you are on, the tariff category printed on the bill will tell you, or your distribution company office can confirm it.

The Lines That Appear on Most Bills

Bill layouts differ between distribution companies, but the same ideas appear under similar names:

• Previous balance or arrears: anything left unpaid from earlier bills. This is added before anything else.
• Import units and import charges: your grid consumption for the month and what it costs.
• Export units and export credit: your solar surplus and the credit it earned.
• Fixed charges and meter rent: flat monthly charges that apply even if your net units are zero.
• Taxes and surcharges: GST, fuel price adjustment, and any other levies your distribution company applies. These are calculated on the import side in most cases, so a high-import month can still produce a large tax line even when your solar system is working well.
• Credit carried forward: unused export credit moved to the next bill. Watch this line every month. If it suddenly drops to zero without explanation, ask your distribution company why.
• Amount payable: the final figure after credits, charges, and arrears. If your credit is larger than your charges, this line may show zero or a carried-forward balance instead of a payment.

A Simple Worked Example

Imagine a month where your home imported 300 units and exported 400 units. The bill first records both. The 100 extra exported units do not disappear: they become a credit carried into next month. Your payable amount for this month is made up of the fixed charges and taxes, minus any credit already carried in from last month. Note that the credit is in money, not units: because export units are valued at the export rate and import units at the import rate, 100 extra exported units do not cancel 100 imported units exactly. For a fuller estimate of what your system saves, see our Solar Net Metering Savings Calculator.

Winter Low-Export Confusion, Explained

Winter is when most solar owners first think something is wrong. Three things happen at once. Days are shorter, so panels have fewer generating hours. The sun sits lower in the sky, so each hour produces less. And fog and smog in December and January block sunlight for days at a time. At the same time, your home still imports at night, and winter nights are longer, so night-time import rises just as export falls.

The result is a bill that looks much worse than a summer bill, even though your appliances and habits did not change. The export credit shrinks, the import charge grows, and the payable amount jumps. This is normal seasonal behaviour, not proof of a fault. The right comparison is the same month last year, not last month. If winter exports fall far below last winter, after allowing for foggier weather, then check for dust, new shading, or an inverter problem. Our guide to solar panel output in winter explains the seasonal drop in detail.

One more winter trap: judging a new system by its first winter. A system installed in November will show its worst months first. Judge it over a full year, across summer surplus and winter shortfall, before deciding whether it is undersized.

Three Checks to Do Every Month

First, match the bill readings with your green meter. Take a photo of the meter on reading day if you can, so you have proof if the numbers disagree.

Second, track your export credit across months. Keep a small notebook or a phone note with three columns: import units, export units, and credit carried forward. If the credit stops growing in sunny months, your system may have a fault, a panel may be shaded, or the inverter may be tripping. The bill is often the first place a system problem shows up.

Third, check whether your bill is estimated. An estimated bill uses guessed readings instead of real ones, and it can badly distort both the import and the export figures. If your bill says estimated and the numbers look wrong, submit your actual meter reading through your distribution company channel and ask for a corrected bill.

When to Complain

Contact your distribution company if any of these happen: the import and export registers on the bill do not match your meter, your export credit vanishes without explanation, the bill shows units for a month when your system was off, or the amount payable jumps sharply while your usage did not change. Take your CNIC, a copy of the bill, and a photo of the meter reading. Keep a copy of your complaint reference number until the corrected bill arrives. For the application side of the process, see our net metering process guide, and for a plain bill lookup, our Electricity Bill Check tool.

What This Bill Does Not Tell You

Your bill shows units and money, but it does not tell you whether your solar system is healthy. A system can produce less than it should for months while the bill still looks plausible, because the grid simply covers the gap. Once a quarter, compare your export units with the same months last year, allowing for weather.

Reading your net billing bill is a five-minute monthly habit, and it is the habit that protects your solar investment. The two numbers that matter most are import units and export units, the line that matters most after them is credit carried forward, and the number you actually pay is the amount payable after all of those are combined.

Frequently asked questions

What are import and export units on my solar net billing bill?

Import units are the electricity your home took from the grid, usually at night or on cloudy days. Export units are the extra solar electricity your panels sent back to the grid during the day. Your green meter records them in separate registers, and your bill shows both.

Why do I still have to pay when I exported more units than I imported?

Under net billing, exported units are credited at a different rate from the rate charged for imported units, and fixed charges and taxes still apply. A month with more exports than imports usually leaves a credit carried forward, not a zero bill.

What does credit carried forward mean on a net billing bill?

It is the value of your unused exported units, moved to your next bill to reduce what you owe. Track it every month. If it drops to zero without explanation, ask your distribution company why.

What are peak and off-peak lines on a solar bill?

Some consumers are on a time-of-use tariff, where electricity costs more during evening peak hours and less during off-peak hours. On such bills the import units are split into peak and off-peak registers, each charged at its own rate. If your bill shows no peak split, you are on a flat-rate tariff and this section does not apply to you.

Why is my solar bill higher in winter even though my usage did not change?

Winter days are shorter, the sun sits lower, and fog blocks sunlight, so your panels export far fewer units while your home still imports at night. The export credit shrinks and the payable amount rises. Judge your system over a full year, not by a single winter month.