Commercial Solar ROI Calculator (South Africa)
Analyze the financial return of your commercial solar investment using SA tax codes.
Project Inputs
Total Gross System Cost (R)
[?]
Total cost of the solar system before any incentives. Include panels, inverters, racking, labor, permits, etc.
System Size (kW)
[?]
The total power output of your solar panel system in kilowatts (kW).
Section 12B Tax Allowance (%)
[?]
The Section 12B tax incentive allows for an accelerated depreciation on renewable assets. A temporary 125% allowance is available from 1 March 2023 - 28 Feb 2025.
Corporate Tax Rate (%)
[?]
Your business's corporate income tax rate. The standard rate in South Africa is currently 27%.
Annual Energy Production (kWh)
[?]
Estimated total kilowatt-hours the system will produce in one year. A common estimate for SA is 1,600 - 1,800 kWh per kW of system size.
Avg. Electricity Rate (R/kWh)
[?]
The average blended rate you pay for electricity from the utility (e.g., Eskom or your municipality).
Utility Rate Escalation (%/yr)
[?]
The expected average annual increase in electricity prices from the utility. NERSA approved increases have been significant.
Annual O&M Cost (R)
[?]
Annual Operations & Maintenance costs. Includes cleaning, inspections, and potential inverter replacement.
Panel Degradation Rate (%/yr)
[?]
Solar panels lose a small amount of efficiency each year. A typical rate is 0.5%.
System Lifespan (Years)
[?]
The analysis period. Most solar systems are warrantied for 25 years.
Calculate ROI
Financial Analysis
Payback Period
- years
Net Profit (25 yr)
R -
Internal Rate of Return (IRR)
- %
Net System Cost (After Tax Incentive)
R -
Cumulative Cash Flow Over Time
Total Lifetime Savings
R -
