Mbona Solar Proposal

Just an idea to make our water pumps run greener and cheaper in the long run.
Project Overview
• System: 15kW hybrid inverter + 15kWp solar (18 × 590W panels) + up to 20kWh batteries
• Location: Pump house, Howick, KwaZulu-Natal
• Baseline Consumption: ~23,600 kWh/year (from pump meter invoices)
• Current Eskom Cost: ~R8,600/month (~R103,800/year)
Key Benefits
• Immediate savings on Eskom bills (~R100k/year).
• Payback in under 3 years (Option 3).
• Resilient backup during loadshedding.
• Scalable, future-proof design.
• Long-term savings exceeding R1.5 million (10 years, with tariff increases).
H48_ralf Fri 29 Aug 2025 8:42AM
Thanks for taking initiative in this regard Nick! Can you share the calcs? A few thoughts: a) Let us compare solutions with and without battery because that is the highest capital cost item and we may get sufficient pumping out of sunshine hours alone without having to invest in batteries - these could always be added at a later stage if beneficial. b) Solar will only offset the Eskom energy charge but we still have to pay the capacity/basic charge which is substantial - did you take this into account?

Nick Costaras Fri 29 Aug 2025 10:11AM
Im adding a pdf with all the calculations and options. Option 1 is no batteries.
Julie · Fri 29 Aug 2025 7:25AM
Very interesting!