Credit: Businesstech.co.za Staff Writer15 August 2022
South Africa imported solar PV panels worth nearly R2.2 billion in the first five months of this year alone, a Reuters analysis of customs data has found.
That amounts to over 500 megawatts of peak generating capacity, analysts say. Once installed, the panels will increase the 2.1 gigawatts of estimated existing small-scale solar generating capacity by some 24%, surpassing what the government has managed to procure in a decade of its utility-scale solar strategy, Reuters said.
“It’s completely unrecognised by the government as to how big an industry it’s become,” said Frank Spencer, spokesman for the South African Photovoltaic Industry Association. “It’s a silent revolution.”
The ongoing decline in Eskom, leading to more frequent blackouts in 2022, has increased the urgency of finding alternatives among those who can afford it.
“Over the past, I’d say 24 months, we’ve seen a continuous increase, month on month in demand,” he said. “We’re seeing interest across the board,” said Tabi Tabi of Granville Energy.
In July, president Cyril Ramaphosa announced an ‘energy action plan’ to tackle the country’s power crisis.
“The shortage of electricity is a huge constraint on our economic growth and job creation,” Ramaphosa said in his speech. “It deters investment, it reduces our economy’s competitiveness. What the most recent load shedding has made clear is that the actions we have taken, and the actions that we continue to take, are not enough.”
Ramaphosa said Eskom will establish a pricing structure to allow those with solar panels to sell electricity they do not need back to the utility, Reuters reported. However, most systems are not registered and feed nothing back onto the grid.
In Johannesburg alone, it is estimated that there are more than 20,000 unregistered solar systems, most of them residential, and despite a legal requirement to have them registered.
Gregor Kuepper, managing director of SolarWorld Africa, says there has been a marked uptake in renewable energy solutions.
“Solar used to be only a solution for large-scale businesses or those with adequate space to house enough panels to support electricity consumption. Fortunately, and thanks to innovation in this space, homes and small businesses now have several options available to either provide temporary support when there is a power cut, and potentially, long-term relief as the preferred ongoing power source.”
He pointed to different types of energy systems: on-grid (grid-tied), off-grid, and on-grid with backup.
“Grid-tied solar PV systems are most common in South Africa, as these are the most affordable and have the best business case. However, this does not necessarily ensure that you will be able to enjoy that cup of coffee during load shedding. Grid-tied solar PV systems will generally be programmed to switch off during load shedding,” said Kuepper.
He highlighted the various offerings around solar right now
Solution 1 – Grid-tied Photovoltaic (PV) system
A photovoltaic system, also PV system or solar power system, is an electric power system designed to supply usable solar power by means of photovoltaics. The two main components are PV panels (DC power) and a grid-tied PV inverter (DC to AC).
A grid-tied PV inverter converts the varying DC power, from the PV panels, into AC power and feeds it to your household equipment and possibly into the grid.
Grid-tied means the inverter synchronizes the frequency and the output voltage to its connected grid. If solar energy is insufficient, a grid-tied PV inverter switches and starts drawing power from the grid into your home. It ensures there is a seamless power supply.
“This option saves electricity in the long run, no backup is required. The pure PV inverters are grid-tied, this means they require the grid to switch on and convert the direct current (PV) into alternating current power which is required by appliances in your home.”
Solution 2 – On-Grid with Backup
- 2.1 PV and Battery
This is a backup and later self-consumption optimization (SCO) option. Self-consumption contributes to the distribution grid stability by avoiding voltage rise during peak PV generation periods such as the middle of the day and helps to reach higher shares of installed PV in the electricity mix.
“When it comes to PV and battery, this can be served by either a hybrid (meaning PV and battery) inverter or separate battery and PV inverter. Your batteries act as backup power when the grid has failed, e.g. load shedding or a power outage. During a normal day, PV can provide power in a house and charge these batteries. This stored power can then be used during the night which is what we call SCO.”
- 2.2 Battery Backup
This is purely a backup solution and is usually sized to make sure that your essential loads are up and running during load shedding/power failure. Under the banner of pure battery backup, you also have various options, such as a UPS, battery together with a charge controller and then of course battery and battery inverter. Of these, a battery with a good and reliable battery inverter is the most reliable solution.
- 2.3 Battery and hybrid inverter
This is the same as the battery and battery inverter option except consumers have an opportunity to install PV panels at a later stage and do not have to add the extra cost of a PV inverter, as it would be PV-ready.
Solution 3 – Off-grid
In the current South African energy climate, this option sounds very enticing. It does however require careful planning and sizing of your system. You would require a large enough PV array to serve your daily loads and charge the batteries for use at night.
And in turn, a large enough battery bank to serve the loads during the evenings and possibly during daytime, when there is not enough PV generation. There is of course the option to add a generator or to use the grid as backup.
