Solar vs Generator — Full Comparison 2026
Enter your details to see a personalised side-by-side comparison. Real costs, real numbers, for your situation.
Your Details
Verdict: For Your Situation
Solar saves you R1,165,823 over 10 years compared to a generator. Solar pays for itself in 8 years — after that, your electricity is essentially free.
Solar Upfront
R150,000 — R240,000
Generator Upfront
R10,000 — R22,000
Solar Monthly Cost
R0
Generator Monthly Cost
R7,644
| Solar (5 kW) | Generator (5 kVA Petrol) | |
|---|---|---|
| Upfront cost | R150,000 — R240,000 | R10,000 — R22,000 |
| Monthly running cost | R0 | R7,644 |
| Monthly Eskom saving | -R1,500 | R0 |
| Payback period | 8 years | Never |
| Noise | Silent | 75 dB (noisy) |
| Maintenance | Clean panels 2x/year | Oil, filters, spark plugs |
| Emissions | Zero | CO2 + noise pollution |
| Lifespan | 25+ years (panels), 10-15 (battery) | 5-10 years |
| Works when grid is on? | Yes — saves money 24/7 | No — sits idle |
| Resale value | Increases property value 3-5% | Depreciates to near-zero |
Total Cost Over Time
Solar costs go negative (you're making money) once it pays for itself. Generator costs only go up.
| Year | Solar Net Cost | Generator Total Cost | You Save With Solar |
|---|---|---|---|
| 1 | R177,000 | R107,728 | R-69,272 |
| 3 | R134,261 | R313,786 | R179,525 |
| 5 | R80,649 | R554,132 | R473,483 |
| 7 | R13,398 | R850,471 | R837,073 |
| 10 | -R120,877 | R1,360,823 | R1,481,700 |
| 15 | -R476,035 | R2,538,609 | R3,014,644 |
| 20 | -R1,101,944 | R4,245,653 | R5,347,597 |
| 25 | -R2,205,010 | R6,769,862 | R8,974,872 |
* Solar savings assume 12% annual Eskom tariff increase. Generator fuel assumes 8% annual fuel price increase. Generator replaced every 7 years.
When Does a Generator Make Sense?
Choose Solar If:
- You own your home (renters can't install)
- You can afford the upfront cost (or solar finance)
- You plan to stay in the property 3+ years
- You want to reduce your Eskom bill permanently
- Noise and fumes matter (neighbours, body corporate)
Choose a Generator If:
- You rent and can't install solar
- You need backup TODAY (solar takes 1-4 weeks to install)
- Your budget is under R10,000
- You only need backup for occasional outages
- You're in a temporary location
Solar vs Generator: The Bottom Line
For most South African homeowners, solar is cheaper over 5-10 years. The upfront cost is higher, but zero running costs and 25+ year lifespan mean solar pays for itself — and then keeps saving you money for decades.
Generators make sense for short-term, temporary, or budget-constrained situations. If you rent, need backup this week, or have less than R10,000 to spend, a generator is the practical choice.
The worst financial decision? Running a generator long-term. At Stage 4 load shedding, a 5kVA generator costs R3,000-R5,500/month in fuel. Over 5 years, that's R180,000-R330,000 — more than a solar system that would have paid for itself.