What does solar actually pay back under net billing?

Questions about payback and return

What is a realistic solar payback period in Pakistan?

For an industrial or commercial site with a daytime load — a mill, a cold store, a processing plant — two to four years is realistic, and the fastest projects I have delivered sit under two. For a domestic system on an unprotected tariff with someone home during the day, three to five years. For a house that is empty until evening, longer, because most of the generation is exported at the buyback rate. Anyone quoting a blanket payback figure without asking when you use electricity is guessing.

How does net billing change the payback calculation?

It splits your generation into two streams worth very different amounts. Units you consume as you generate them save you the full retail tariff — currently in the region of PKR 50 to 60 for most commercial and unprotected domestic consumers. Units you export earn the buyback rate, which is roughly a third of that. Before February 2026 the two were near parity and the split did not matter. Now it is the single biggest driver of payback, which is why this calculator asks when you use electricity before it asks anything else.

Does this calculator assume electricity prices keep rising?

It assumes 8% a year by default, and the field is editable so you can set it to whatever you believe — including zero. Eight percent is deliberately conservative: Pakistani electricity tariffs have risen considerably faster than that over the last decade. A payback figure that flatters itself with an aggressive escalation assumption is what a salesman produces. Setting it to zero shows you the payback on today's prices alone, which is the floor rather than the expectation.

Does the model account for panel degradation and inverter replacement?

Yes to both, and a projection that omits them is a brochure rather than a model. The array is degraded 0.5% a year, which removes roughly a tenth of cumulative output over the modelled life. An inverter replacement is charged in year twelve at 12% of the original system cost, because a string inverter carries a five to ten year warranty and a real service life closer to twelve to fifteen. Annual maintenance is charged every year. All three make the payback figure longer and more honest.

Can I trust a payback figure from a company that wants to sell me solar?

Check it rather than trusting it, which is why every figure this page uses is listed with its source and the date it was verified. Also check the incentive: I take no margin on equipment and I am paid 4% only once a system is commissioned and generating. A projection that overstates the return gets a client who is disappointed with a system I am personally answering the phone about for the next decade. The honest number is the one that serves me too.

What return on investment does solar give in Pakistan?

On a well-matched industrial load, a system that pays back in three years and runs for twenty-five returns several times its cost over its life, even after inverter replacement and maintenance. But lifetime ROI is the wrong figure to decide on, because it is dominated by assumptions about tariffs twenty years out that nobody can defend. The payback period is the number worth arguing about — it depends mostly on facts you can check today.

Why does my quoted system show a worse payback here than the vendor claimed?

Usually one of three reasons. The vendor valued all generation at the retail tariff rather than splitting it between self-consumption and export, which overstates the saving on any system that exports. Or the projection assumed no degradation, no maintenance and no inverter replacement. Or the system is simply larger than your daytime load justifies, so the last increment of capacity is earning the buyback rate. Enter the capacity you were quoted above and the split will show you which.