How much you will pay to cancel Eskom and go off-grid
Load-shedding has once again become a daily reality in South Africa, and experts predict that South Africans should brace for many more years of rotational blackouts in the country.
The CSIR recently published a presentation which said South Africans should expect load-shedding to get significantly worse over the next three years.
Energy expert Ted Blom agreed with the CSIR’s findings and added that his own projections extend to load-shedding for at least the next five years after Eskom signed on the opening of new coal mines to feed its current coal fleet.
Blom said that the predictions could change if Eskom decided to start importing extra power from power barges or new power islands.
To manage the disruptive impact of load-shedding, South Africans with the means are looking for ways to break their dependence on Eskom for electricity.
Whether through using backup generators or batteries and solar power, many people are searching for ways to beat the blackouts.
This raises the question: how much would it cost to go completely off-grid and not have to rely on Eskom at all?
Building a solar power plant for your home is expensive
Greg Blandford, the director at Rubicon Renewables, said that the issue is a complex one.
“There are so many factors to consider, but ultimately it will require a lifestyle change for the client to live off the grid – or close to that – without being ridiculously expensive,” Blandford explained.
He added that there are general ways to tackle the problem:
Add solar and energy storage to cover current power usage as-is.
Perform an energy efficiency audit prior to installing solar power and batteries.
Blandford said that trying to cover your existing power usage without an energy efficiency audit is unwise unless money truly is no object.
“We have seen customers follow this route and invest in multiple battery packs and solar totalling many hundreds of thousands or millions of rands.”
The wiser option is to consider the cost of energy storage.
“Even though lithium battery technology, and other higher-end energy storage, continue to fall in price the overall cost of the system can be mitigated if energy efficiency measures are implemented first,” stated Blandford.
This includes replacing electric stoves and hobs with gas appliances, replacing all older lighting systems with LED lighting products, and replacing standard hot water geysers with solar geysers or heat pumps.
A final step to consider is to replace appliances such as fridges, freezers, and washing machines with energy-efficient variants that have an A+++ rating or more.
“The A rating of an appliance such, as A+++, means it is 30% more energy-efficient than a standard A-rated appliance,” Blandford said.
To illustrate these basic principles, Blandford provided two examples of off-grid installations for three-bedroom suburban homes in Johannesburg to highlight the difference in price.
He emphasised that the costs he gave are indicative only, as each off-grid system will be slightly different.
“There are many product options to suit various budgets, so this is a median of some of those options. Every solution will be bespoke to the client, so these are budgetary values.”
No energy efficiency audit – R350,000
For the first scenario, Blandford considered a family home in Johannesburg with no grid feedback allowed:
Standard appliances (no gas)
This installation assumes an average monthly power usage of 1,200kWh per month or 40kWh per day, with most usage of power during sunlight hours (25-30kWh) and 10kWh after sunset.
Blandford said that such a home would require a solar panel array of approximately 8kWp and a battery system of at least 15kWh.
The solar would produce on average 40kWh per day over the year if the power produced was fully utilised and any excess energy then stored in the battery for night-time consumption.
A solution of this size would cost in the region of R300,000 to R350,000, which includes installation.
The package would include around 20× solar panels of 400Wp each, a standard solar grid-tied inverter, Tesla Powerwall, and balance of system components to install the kit.
With energy efficiency audit – R240,000
For the second scenario, Blandford considered a similar home:
1 geyser (solar or heat pump)
A small pool with a 1kW pump
This installation assumes an average monthly power usage of 700kWh per month, or 23kwh per day, with most usage of power during sunlight hours (15kWh) and 8kWh after sunset.
Blandford said that such an installation would require a solar panel array of approximately 5kWp and a battery system of at least 7kWh.
The solar panels would produce on average 25kWh per day over the year if the power produced was fully utilised and any excess energy then stored in the battery for night-time consumption.
A solution of this size would cost in the region of R215k to R240K, including installation.
The package would include around 12× solar panels of 400Wp each, a full hybrid 5kWp inverter, a 7kWh lithium battery pack, and the balance of system items to install the kit.
“In a nutshell, there are many products and solutions available in South Africa from the very basic backup for a few thousand rands for a TV, light, and Wi-Fi, to super high-end systems for multi-million rand homes,” Blandford said.
“It all depends on the need of the customer and budget requirements.”