We are often asked what the payback period is for a solar system.

To find out we looked at 5 Newfield customers with similar systems – Newfield Flex with 6 solar panels, a 5kW inverter, a 5kWh hour Li ion battery and an efficient ceramic geyser element. The data presented is actual metered data.

These systems do not feed back to the utility grid and use solar power to keep the battery charged – the battery is used for some night time consumption and during power outages. The systems power all lights, most plug circuits and the energy efficient geysers.

The price of the systems as installed ranged from R100,000 to R120,000. 

We have used the City of Cape Town Home User tariff in our calculations. This is a 2 tier tariff where the costs are related to usage.

Using the above tariffs we calculated the following based on data for the year January 2025 to December 2025. This is actual data extracted from monitoring systems. An annual saving of R 19,798 is calculated. What is important to note is that the more expensive tier 2 above 600 kWh has been eliminated completely. The service charge is included in the calculations.

Annual generation data 2025

  

The payback period will continue to decrease with each tariff increase. The systems have the ability to feed back to the utility grid, which could increase savings and reduce the payback period even further. 

Capital repayment term