What You Need for an Off-Grid Solar System in South Africa

If you need power in a remote area or have simply had enough of South Africa’s fractured national grid, an off-grid solar system is what you need.

South Africans who want to produce their own power can use solar panels to generate electricity and a lithium-ion battery for solar to store it.

We explain how to get the best off-grid solar system South Africa has to offer. In this article, we discuss:

• the costs of going off grid
• factors that affect the design
• the equipment you’ll need
• the best off-grid batteries.

What it costs in South Africa to get off the grid

Off-grid systems are not connected to the local electricity network. If you want to be completely independent of Eskom, it does require quite a large initial investment.

While there has been a trend of decreasing prices for self-powering energy solutions in the past few years, global factors have reversed this in the short term.

Factors include higher prices for commodities to make system components, the increased cost of solar panels due to constrained supply, higher international shipping costs and a general shortage of semi-conductors for electronic equipment.

Despite this, the ever-increasing cost of energy in South Africa now makes it economically viable to go off grid and get the capital costs back with a return inside the life of the equipment. According to GreenCape, the cost of a solar system can be repaid within just five years.

So, what’s a realistic off-grid solar system price in South Africa? The range you can expect to pay to take your home completely off grid is between R150,000 and R350,000.

If you have a four-person, three-bedroom, two-bathroom home using around 25 kWh per day, the cost of an off-grid solar system with battery storage is about R200,000 to R250,000, including installation.

A smaller household could pay as little as R150,000. A premium system with complete autonomy could cost more than R650,000. And you can pay more than R1 million.

Factors affecting off-grid solar system design

There is, of course, not a one-size-fits-all off-grid solar system design. The solution, and therefore the cost, will depend on various factors.

Before you consider a system design, you should first perform an energy-efficient audit. The goal is to achieve maximum energy efficiency in your home before designing an off-grid solar system.

If you make energy-efficient changes in your home, you’ll reduce the capacity needed. This will reduce the cost of your off-grid solar system.

Many off-grid homes use a combination of energy sources, not just one in isolation.

Start by changing the most power-hungry appliances to alternative power supplies. Convert your hob and stove to gas and your hot-water geyser to solar.

Replace old appliances (fridge, freezer, washing machine, dishwasher) with new, energy-efficient models. Switch all lights to LED options.

Once you’ve done this, factors affecting the off-grid solar system design include:

• system size – power and capacity
• roof details – size and pitch of roof with sun exposure
• autonomy – how long the system must provide power during periods of low generation
• budget – how much you can spend.

What equipment you need for an off-grid solar system

Every off-grid solar system needs similar components to start with. Here are the essential pieces of equipment you’ll need and what they do.

Solar (PV) panels

The solar photovoltaic (PV) panels are the most obvious part of an off-grid solar system. They convert solar energy to electrical energy, which is then stored in a battery.

Solar cells (small squares) make up a panel. The most cost-effective panels contain between 60 and 72 cells. The more cells, the larger the panel. A typical 60-cell panel will output 300 to 375 watts.

In South Africa, solar panels are typically mounted on a north-facing pitched roof to maximise exposure to the sun’s rays. Today’s panels last between 25 and 40 years.

Charger control

The DC power the solar panels produce is wired through the charger control before it goes to the battery bank where it’s stored.

The charge control’s function is to manage the flow of energy from the solar panels to the batteries.

It’s a critical component because it determines the efficiency of the entire solar system. It makes sure the batteries are charged properly and protects them from being over-charged. This is important for the longevity of the battery bank.

The charger control also eliminates any reverse current flow from the batteries back to the solar modules at night.

Inverter

The function of the inverter is to convert the DC current from the solar panels into AC current, which most household appliances use.

Modern inverters are efficient and very effective. The conversion takes place in real time. Good quality inverters produce pure, stable electricity without dips and surges. This results in appliances working better.

Inverters come in various sizes, which can accommodate smaller or larger loads, depending on what’s required.

Some inverters are all-in-one units, combining charge controllers, battery management, seamless switchover from different power sources and computerised operation.

You can expect a good inverter to last for 10 to 15 years.

Battery bank

The last, most important – and most expensive – component in an off-grid solar system is the battery bank.

Excess energy during the day is stored in battery banks in order to provide electricity when there’s no sunlight, in the evening and at night.

In the solar power industry, the two most commonly used battery types are lithium and lead acid. Lithium iron phosphate (LiFePO₄) is the chemistry makeup of most lithium batteries used in the solar power industry.

There’s no doubt that a lithium-ion battery for solar has many advantages over lead-acid batteries and is the best choice for off-grid applications. In comparison, the many benefits include:

• safer chemistry and no toxic acid
• no gas emitted
• stored without ventilation
• lighter and requires less space
• maintenance free
• doesn’t need to be fully charged
• charges faster
• greater depth of discharge
• higher capacity
• longer lifespan
• easy to scale existing battery bank
• 10-year warranty.

What we offer at REVOV: the best batteries for going off grid

At REVOV, we offer a selection of the best batteries for an off-grid solar system for your home or office.

REVOV offers LiFe and 2nd LiFe lithium solar batteries. They’re the ideal batteries for an off-grid solar system in South Africa due to their high efficiency, compact design and long lifespan.

Our LiFe and 2nd LiFe batteries are lithium-iron phosphate batteries (LiFePO₄) – the best lithium batteries for solar systems.

Our 2nd LiFe batteries, which were previously used in electrical vehicles, are significantly cheaper than traditional lithium batteries, are safer and less toxic, offer exceptional performance and durability, and come with 10-year warranties.

We also offer 2nd LiFe all-in-one units, the Cube. They’re compact, fully-integrated units that are ideal for solar energy storage for smaller offices and homes.

If you’re an installer looking for solar batteries for an off-grid solar system, contact us to find out more about our LiFe and 2nd LiFe batteries. We’ll be happy to help.