Zero feed-in: what it means when the grid will not take your surplus

Clients who have read about solar in Europe or North America often assume a system exports what it does not use, and that the meter runs backwards. In Uganda it does not work that way for commercial and industrial users, and that difference shapes how every system gets sized.

No net metering, so no export

Uganda has no net metering, the arrangement where the utility credits you for power you send back, for commercial and industrial connections. Systems are therefore configured for zero export, which means the inverter actively limits output so that nothing flows back into the utility network. Everything the panels produce is used on site, or it is not produced at all.

This also keeps the relationship with the utility simple. Backfeed, meaning power flowing back into the network, is what utilities care about, and with export limiting set correctly the system never creates it, so having solar on site is not in itself a reason for disconnection.

Why it drives the sizing

If surplus has nowhere to go, any capacity above the daytime load is curtailed, which means it is held back unused. An array sized 30 percent above what the site consumes in daylight does not produce 30 percent more value, because it produces the same value at a higher cost.

So the sizing question becomes a question about your load: what the site actually draws between roughly nine in the morning and four in the afternoon, on a working day and on a quiet day, and how much of that is steady enough to design against. This is why we ask for consumption data, or install logging equipment, before quoting anything above a small system.

Where storage changes the answer

Storage is what converts curtailed surplus back into value, by moving midday production into the evening or into an outage. That makes a battery worth its cost on a site with meaningful evening load or a real reliability problem. On a site whose consumption is purely daytime, the same money usually does more in additional panels.

The approvals side

For grid-tied systems we prepare the applications for the utility and the regulator, set the system for zero export and manage the approval process. The work is procedural more than difficult, and it belongs with whoever builds the system.