Difference Between On-Grid, Off-Grid and Hybrid Solar Systems

Quick answer: an on-grid (grid-tied) system has no batteries, costs the least and cuts your electricity bill, but switches off during a power cut. An off-grid system runs entirely on solar and batteries with no connection to Eskom or the municipality, so it costs the most and suits remote properties. A hybrid system combines solar, batteries and the grid, so it lowers your bill and keeps the lights on during outages. For most homes in Durban and other South African cities, a hybrid system is the best all-round choice.

The three types of solar system explained

Every home solar system uses the same core parts: solar panels that turn sunlight into direct current (DC) electricity, and an inverter that converts it into the alternating current (AC) your home uses (see how solar panels work). What makes the three types different is whether they are connected to the grid and whether they store energy in batteries.

What is an on-grid (grid-tied) solar system?

An on-grid solar system, also called a grid-tied system, is connected to your Eskom or municipal supply and has no batteries. Your home uses solar power first and draws from the grid whenever the panels are not producing enough.

How an on-grid system works

1.     Solar panels generate DC electricity during the day.

2.     A grid-tied inverter converts it to AC power for your home.

3.     Your appliances use the solar power first.

4.     Any surplus can be exported to the grid, where your municipality allows it and your system is registered.

5.     At night and on cloudy days, your home draws power from the grid as normal.

Why on-grid systems switch off during power cuts

Grid-tied inverters have a safety feature called anti-islanding. When the grid goes down, the inverter shuts off immediately so it cannot send electricity into lines that technicians may be working on. This means an on-grid system gives you no power during loadshedding or an outage, even when the sun is shining.

Pros and cons of on-grid solar

Best for: homeowners and businesses who mainly want to reduce their electricity bill and are comfortable without backup power, or who use most of their electricity during the day.

What is an off-grid solar system?

An off-grid solar system has no connection to Eskom or the municipality at all. Solar panels charge a battery bank, and the batteries power your property day and night.

How an off-grid system works

1.     Solar panels generate electricity during the day.

2.     An off-grid inverter and charge controller charge the battery bank.

3.     The inverter supplies your home from the panels and batteries.

4.     When the batteries run low, a backup generator is often used, because there is no grid to fall back on.

Sizing an off-grid system properly

Because there is no grid backup, an off-grid system must be designed for the worst case: several cloudy days in a row in winter, when the sun is lowest and days are shortest. That usually means more panels and a much larger battery bank than a hybrid system, and careful management of heavy loads such as geysers, ovens and pool pumps. Many off-grid homes switch these to gas or solar water heating.

Pros and cons of off-grid solar

Best for: farms, holiday homes and rural properties where connecting to the grid is not possible or would cost more than the system itself. In Durban and other cities, going fully off-grid is rarely the most cost-effective option.

What is a hybrid solar system?

A hybrid solar system combines solar panels, batteries and a grid connection. A hybrid inverter manages all three, deciding moment by moment whether to use solar power, charge or draw from the batteries, or use the grid.

How a hybrid system works

1.     During the day, solar panels power your home.

2.     Surplus solar energy charges the batteries.

3.     In the evening, your home runs on stored battery power.

4.     During a power cut, the system switches to batteries automatically, usually within milliseconds.

5.     If the batteries run low and the grid is available, the system tops up from the grid.

Backup loads versus whole-home backup

Many hybrid systems are designed to back up essential circuits only, such as lights, plugs, Wi-Fi, TVs, the fridge and the gate motor, while high-demand appliances like the geyser, stove and pool pump run on solar and the grid. This keeps the battery size, and the cost, down. Your installer should explain exactly which circuits will stay on during an outage. Lithium batteries are now the standard choice; our gel vs lithium-ion battery guide explains why.

Pros and cons of hybrid solar

Best for: most homes and small businesses in South Africa that want both lower bills and protection from outages. See a real example in our Hillcrest hybrid solar case study, and read whether solar battery storage is worth the cost.

How much does each system cost in South Africa?

The biggest difference in price between the three system types is the battery. Typical installed prices in 2026 for a 10 kW home system are:

Source: EnergyBee, 10 kW solar system price in South Africa (2026). A 10 kW system needs roughly 38 to 52 m² of roof space. If your home has a three-phase supply, budget an extra R15,000 to R30,000. Final prices depend on equipment brands, battery size, roof type and access. See our solar packages or ask us for a quote based on your home.

Running costs matter too. An on-grid system has the fastest payback on bill savings alone, because there is no battery to pay off. A hybrid system costs more, but also cuts your evening electricity use and protects you from outages. An off-grid system removes your electricity bill entirely, but the battery bank will need replacing during the system’s life.

Rules for grid-connected solar in Durban (eThekwini)

If your on-grid or hybrid system is connected to the grid in Durban, it must comply with eThekwini Municipality’s rules for small-scale embedded generation (SSEG):

•       Registration: systems that can export power to the grid must be registered with eThekwini Electricity, with an application submitted before connection.

•       Approved inverter: the inverter must meet the NRS 097 grid-connection standard and carry the relevant certificate.

•       Certificate of Compliance: every installation, including off-grid and non-exporting systems, needs an electrical CoC from a registered electrician.

•       Export credit: with an approved bi-directional meter, power you export can be credited to your municipal account.

•       Export limits: eThekwini caps exports by connection size, and some areas may be limited further, so an export limiter is often recommended.

Fully off-grid systems that never connect to the grid don’t need SSEG registration, but still need a CoC. A good installer will handle the paperwork for you. (Source: SurgePV, eThekwini solar compliance)

How to choose the right system for your property

Three questions decide it for most people.

1. Is a grid connection available and reliable?

If your property has no grid connection, or connecting would be very expensive, off-grid is the practical answer. If you are on the grid, an on-grid or hybrid system will almost always cost less than going fully off-grid.

2. Do you need power during outages?

If you work from home, run a business, rely on medical equipment, or simply want the lights, Wi-Fi and gate motor to keep working during a power cut, you need batteries, which means a hybrid system. If outages don’t affect you much, on-grid is the cheaper route.

3. When do you use the most electricity?

If most of your usage is during the day, an on-grid system can cover a large share of it. If your usage peaks in the evening, as it does in most family homes, a hybrid system lets you store daytime solar power and use it after sunset.

Quick decision guide

Tip: if budget is tight, ask your installer about a hybrid-ready inverter. You can start with panels only, then add batteries later without replacing the inverter.

Frequently asked questions

What is the main difference between on-grid and off-grid solar?

An on-grid system is connected to the electricity grid and has no batteries, while an off-grid system has no grid connection and relies entirely on solar panels and batteries.

Does a grid-tied solar system work during loadshedding?

No. Grid-tied inverters shut down automatically when the grid goes down, for safety. To keep power during outages, you need batteries, which means a hybrid or off-grid system.

Is a hybrid system better than on-grid?

It depends on what you want. A hybrid system costs more but gives you backup power and lets you use solar energy at night. An on-grid system is cheaper and pays back faster if bill savings are your only goal.

Can I add batteries to an on-grid system later?

Usually, yes, but a standard grid-tied inverter often has to be replaced with a hybrid inverter. If you think you may want batteries later, choose a hybrid-ready inverter from the start.

Can a hybrid system run without the grid?

Yes, during outages it runs on solar and batteries. For extended periods it is limited by battery size, and most hybrid systems are not designed to run a whole home indefinitely without the grid.

Do I need to register my solar system in Durban?

Yes, if it is connected to the grid and can export power. eThekwini requires SSEG registration, an approved inverter and a Certificate of Compliance. Fully off-grid systems don’t need SSEG registration but still need a CoC.

Can I sell electricity back to the grid?

In eThekwini, a registered system with an approved bi-directional meter can receive credit for exported power on its municipal account. The credit rate is lower than what you pay for grid electricity, so using your own solar power is usually worth more than exporting it.

Which solar system is best for a home in Durban?

For most Durban homes, a hybrid system offers the best balance of lower bills and backup power. On-grid suits homes focused purely on savings, and off-grid is best kept for properties without a grid connection.

Get expert advice from EagleEyeSolutions

Choosing between on-grid, off-grid and hybrid solar comes down to your usage, your budget and how much backup you need. EagleEyeSolutions designs and installs all three types for homes and businesses across Durban, Ballito and the Upper Highway, from our base in Kloof.

We visit your property, review your electricity usage, and recommend the system that fits your needs and budget, with a fully itemised quote and all compliance paperwork handled for you.

•       Phone: 031 764 7087 or 082 443 0230

•       Email: mark@eagleeyesolutions.co.za

•       Online: book a site assessment

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