Net metering · Faisalabad, Lahore, Punjab

How long does solar take to pay for itself under net billing?

Short answer

It depends mostly on how much of your solar you use yourself. Each unit you use saves your full slab tariff; each unit you export earns only the buyback rate. The more you self-consume, the faster the payback.

That is why systems sized to your own daytime load, with a battery for the evening, pay back faster under net billing than oversized export systems. We calculate it from your bills rather than quoting a general number.

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The simple calculation

Payback = system cost ÷ yearly saving. Yearly saving = units you use yourself × your tariff + units you export × the buyback rate.

Diagram

Same solar unit, two values

Buyback rate

Used yourself: saves full tariffExported: earns buyback

Faster payback

High daytime useBattery for eveningsRight-sized array

Slower payback

Mostly night useOversized to exportElectric heating

Illustration, not to scale. Tariffs differ between FESCO, LESCO and other DISCOs, and the buyback rate is revised periodically.

What speeds it up

High daytime use: ACs, pumps, machinery or an office running in daylight.
A battery that moves spare solar to the evening.
Right-sized array: no paying for panels that mostly export.
Clean, unshaded panels.

What slows it down

Most use at night with no battery.
Oversizing to export.
Heavy winter heating on electricity.

Worked out from your FESCO or LESCO bill

Send a FESCO or LESCO bill to our Faisalabad or Lahore office and we will show the payback with and without a battery.