40 flats, one roof, zero solar: apartment buildings cannot split a shared system's billing
Our building committee in Gulshan-e-Iqbal has been trying to install rooftop solar for two years. The roof space is there, the money is collectible, the savings are obvious. What kills it every time is the split: one K-Electric connection per flat, one net metering license per connection, and no legal or technical way to distribute a shared system's output across 40 meters. Every solution proposed turns into either one person owning it (nobody trusts that) or 40 separate tiny systems (absurd on a shared roof). Buildings across Karachi, Lahore, and Islamabad are stuck at exactly this point. Whoever builds the metering hardware plus the legal template plus the billing software for shared residential solar unlocks thousands of rooftops in one move. The demand is literally organized into committees already — they just need something to buy.
A high-conviction problem with strong founder-market fit signals. The combination of severe price asymmetry, accessible demographics, and existing infrastructure makes this buildable within 9 months by a small team.
Solutions · 2
One commercial meter + submetering hardware + a WAPDA-blessed allocation agreement template
The workable structure: the building association takes one commercial net-metering connection for the shared system, submeters each flat's consumption with certified meters, and allocates credits through a standard legal agreement the association signs — the missing piece is that agreement template plus billing software, not hardware. I have done two buildings semi-formally in Faisalabad. A company productizing this (survey, install, legal pack, monthly billing service) could clear the backlog of stuck committees within a year. DISCO buy-in is achievable because it reduces their per-flat paperwork.
Billing engine for shared solar: signal each flat's share from smart submeters, settle in the maintenance bill
The software side is buildable this month: pull readings from LoRa submeters, compute each flat's solar share by an agreed formula (equal, by area, or by usage), and generate a line item in the monthly maintenance bill with settlement tracking. Committees fight about fairness — the fix is transparent math everyone sees in an app. Happy to build the MVP free for one building as a portfolio project if a hardware partner handles meters.
Discussion
I have designed three buildings where the roof was structurally prepared for solar that never came, for exactly this billing reason. The hardware is waiting on paperwork.
Mirpur has entire towers owned by overseas families who would fund shared solar sight unseen. The allocation agreement template is the unlock for diaspora money too.
I have done two of these semi-formally. The engineering takes a week; the committee negotiations took five months each. Whoever productizes the legal pack wins this market.