Inverter vs Generator vs Solar: Which Backup Power Is Right for You?
Updated 2026-07-11
Choosing backup power comes down to three main options: an inverter with batteries, a generator, or a full solar system. None is "best" in the abstract — the right one depends on how long the outages are, what you need to keep running, and your budget. Here's an honest comparison.
The three options at a glance
| Inverter + battery | Generator | Solar system | |
|---|---|---|---|
| Runs during load-shedding | Yes, silently | Yes, while fuelled | Yes, and charges by day |
| Noise | Silent | Loud | Silent |
| Ongoing cost | Grid charging only | Petrol/diesel | Near zero |
| Typical installed cost | R25,000 – R120,000 | R8,000 – R70,000 | R90,000 – R280,000 |
| Cuts your electricity bill | No | No | Yes |
| Best for | Silent, hands-off backup | Cheap upfront, long outages | Long-term savings + backup |
Inverter + battery backup
An inverter charges a battery from the grid when power is on, then runs your essential circuits — lights, Wi-Fi, TV, a few plugs — silently when the grid drops. It switches over automatically, usually within milliseconds, so you barely notice load-shedding.
Good when: you want silent, automatic, maintenance-free backup and mostly need to keep lights, electronics and small appliances alive through a 2–4 hour slot.
Watch out for: it does not generate power, so during extended outages the battery can run flat if it hasn't had grid time to recharge. Sizing the battery correctly (in kWh) matters — see our sizing guide.
Generators
A generator burns petrol or diesel to make electricity on demand. Rand for rand it delivers the most backup power upfront, and it will run indefinitely as long as you keep feeding it fuel.
Good when: you face long or unpredictable outages, need to run heavy loads (geysers, pumps, workshop tools), or want the cheapest possible entry cost.
Watch out for: noise, fumes (never run one indoors or in a closed garage), refuelling, ongoing fuel cost, and manual starting unless you pay for an automatic transfer switch. Wiring a generator into your home's DB board must be done by a registered electrician with a proper changeover switch.
Solar power systems
A hybrid solar system combines panels, an inverter and a battery. It charges from the sun by day, powers your home, feeds the battery for night-time and load-shedding, and can dramatically cut your municipal bill.
Good when: you plan to stay in the home for years, want to reduce your electricity bill as well as beat load-shedding, and have suitable roof space and orientation.
Watch out for: the highest upfront cost, roof and shading constraints, and the importance of correct sizing. Payback periods typically run several years, so it's a long-term play as much as a backup one.
A simple way to decide
- Just want the lights and Wi-Fi to stay on, silently? Inverter + battery.
- Cheapest possible backup, or very long outages, and noise doesn't bother you? Generator.
- Want to cut your bill and be less dependent on the grid, and you're staying put? Solar.
Many homes end up combining approaches — for example an inverter-battery system now, with solar panels added later. Whatever you choose, get a site assessment quote rather than a phone estimate, and check the installer's credentials.