Solar savings calculator

What a rooftop system would do to your bill, worked out the way the bill is actually calculated: solar used at home removes grid units and can drop your slab, exported units earn a credit at the net-billing rate, and the fixed charge stays.

Your summer figure gives the biggest saving; use an average for a fair year.

Average daily output per installed kW. Around 4 in most of Pakistan; lower in winter and in dusty or shaded sites.

Solar generates in the day; what you do not use then is exported. 30 to 50 percent is typical without a battery.

What the DISCO credits for exported units under net billing. Check the figure in your net-metering agreement.

Estimated monthly savingRs 16,182600 units generated · 240 used at home · 360 exported
Bill before solar (before taxes)Rs 27,134
Bill after using 240 solar units at homeRs 14,912
Saving on the billRs 12,222
Credit for 360 exported unitsRs 3,960

Using solar at home drops you from the 501–600 units slab to 301–400 units, which reprices every remaining grid unit. That is most of the saving.

Every assumption above is editable and the result is only as good as them. Export credit is valued at the rate you entered; bill savings use NEPRA's notified domestic rates and this month's adjustments, before taxes.

Before you sign with an installer

  • Ask for the export rate in writing. Net billing pays far less for exported units than net metering did, and the difference changes the payback by years. Our guide to net metering and net billing in 2026 explains the rules.
  • Size for daytime use, not for the whole bill. A system that exports most of its output is earning the low rate on most of its output.
  • Check your slab first. A household at 350 units saves more per panel than one at 700, because the first panels take it across a slab boundary. The bill calculator shows the slabs.
  • The application is through your DISCO. See how to apply for net metering for the documents and the steps.

Frequently asked questions

Why is the saving mostly from the slab drop, not the exported units?
Grid units are charged at the rate of the slab the whole month reaches, and solar used at home cuts the grid units. Falling from 600 units to 300 reprices everything left at a lower rate. Exported units are credited at a much lower rate, so they matter less than installers' brochures suggest.
What export rate should I use?
The rate in your net-metering or net-billing agreement with your DISCO. For new connections in 2026 the press reported a rate around Rs 11 per unit under the net-billing rules, far below the retail rate; older agreements may differ. The field is editable for exactly this reason.
How many units does a 5 kW system make?
Around 4 units per kW per day on average across the year in most of Pakistan, so roughly 600 a month for 5 kW, with summer above and winter below that. Shade, dust and panel orientation all reduce it.
Does solar remove the fixed charge?
No. The fixed charge is on your sanctioned load and slab, and the DISCO bills it whether or not you generate. Only the units change.
Is the payback figure reliable?
It is a simple division of the system cost by the first-year saving. It ignores panel degradation, inverter replacement, tariff changes and any financing cost, so treat it as a ceiling on how good the deal is, not a forecast.