What would export credits be worth to you?

Two answers give a first figure, and they decide most of it: how many panels you have, and when your batteries are full on a sunny day. The panels set how much power you make. The batteries decide how much of it is left over, because they fill before anything goes to the grid. If you don't know your panel count, your inverter's size will do, with a wider range.

Four optional questions narrow the range: how powerful each panel is, what runs in the day (a geyser on a solar timer can take a quarter of a summer day's surplus, and more in winter), whether your supply is single- or three-phase, and which way the panels face. A fifth, how you pay for electricity, changes the verdict rather than the credit.

We model a cloudy, a mixed and a clear day for every month of the year, from twelve years of satellite data for Cape Town (the European Commission's PVGIS), for panels like yours. Your home uses what it needs first, your batteries fill next, and the rest goes to the grid, up to the limit the City sets for your supply: 3.45 kW at a time on a typical single-phase supply, 10.4 kW on three-phase. Most export happens between October and March. In winter the days are short and the batteries take most of what is made.

How much the battery answer matters, for a typical home with 13 panels (about 5.9 kW):

• By 10am: about R410 a month
• By midday: about R350 a month
• In the afternoon: about R180 a month
• Rarely or never: about R10 a month
• No batteries: about R500 a month

Each exported kWh is credited at the City's 2026/27 residential rate of R1.3298 (excluding VAT), which includes a R0.25/kWh incentive that Council reviews every year. The City's R6.80 monthly AMI meter fee comes off. The credit is set against your whole municipal account, not just electricity.

The AMI meter puts you on the City's Home User tariff. On a monthly bill, or with a home valued at R1 million or more, you are on it already and nothing changes. On prepaid with a home valued under R1 million, it adds roughly R90–R260 a month, and the estimate allows for that when you tell us.

No two homes use power the same way, so you get a range as well as a figure. The figure is the typical home with your answers; four in five such homes land inside the range. We tested that against an hour-by-hour simulation of 45,000 Cape Town solar homes on the same weather data, and the range held the real figure for about four in five of them, whether they answered two questions or all of them.

With only the first two answers, the range runs to about half either side of the figure. With every answer it is closer to a third, and tighter still for homes whose batteries are full early. The accuracy label on your result says which you have, rough, fair or good, and which question would narrow it most.

A standard export activation costs R11,651.90 once-off: our fee of R5,000 and the City's AMI meter at R6,651.90. Your result sets that against your credit and shows how long the credit takes to pay it back.

It also asks whether the same money would do more in your bond. Paid in at prime (10.75%), R11,651.90 would save you about R252 a month over 5 years. Export is worth doing when your credit beats that. If it doesn't, the estimator says so plainly, and if your range straddles that mark, it says the call is close. We also check it without the incentive.

Some homes need building work at the supply before the City will meter export. That adds cost, and the free check gives your exact price before you pay anything. For the City's full process, read getting export credits on a home.