South Africa’s current power crisis is expected to last a while, with high chances of load-shedding throughout 2023.
However, several cost-effective backup power solutions are available to help South Africans overcome the country’s rotational power cuts.
Companies such as Mecer, Lalela, RCT, and Ellies produce portable inverter and battery trolleys that South Africans can hook up to their appliances and devices to keep them on during load-shedding.
They are commonly available from retailers including Takealot, Incredible Connection, Leroy Merlin, Builders Warehouse, and GeeWiz.
MyBroadband found some of the cheapest inverter trolleys available in South Africa. We created two separate lists — one for lead-acid and gel batteries, and another for pricier lithium-ion options.
Buyers must research their load-shedding power needs before making a decision, as there are several factors to consider when choosing between lead-acid and lithium-ion batteries.
While lead-acid and gel batteries are significantly cheaper than their lithium-ion counterparts, they can become expensive over time if load-shedding occurs continuously — as it did in 2022.
This is because lead-acid batteries lose capacity relatively quickly each time their charge depletes.
According to GeeWiz, lead-acid and gel battery variations are well-suited for occasional stage 1 and 2 load-shedding as they typically last 150-200 cycles.
It notes, however, that continuous load-shedding and higher stages of power cuts can cause the batteries to deplete within a few months. Most manufacturer warranties are also void after 150 charge cycles.
“During stage 4 to stage 6, we highly recommend turning off the power switch on the inverter itself, when the need for power is not crucial. This will preserve the longevity of the batteries,” GeeWiz advises.
Lithium-ion batteries, while significantly more expensive than lead-acid and gel options, offer over 2,000 cycles before reaching their end-of-life, depending on their depth of discharge.
In addition, lead-acid packs could shed cycles faster if you allow their battery levels to fall below 50%.
Lithium-ion units, on the other hand, could be discharged up to 80-100% of their capacity without any impact on their overall lifespan.
Therefore, even with similarly rated capacities, lithium-ion batteries give almost double the usable energy storage offered by lead-acid cells.
However, it is important to note that discharging to greater depths will still reduce the lifespan of the lithium-ion battery.
Calculating your usage
Determining the power draw of the appliances and devices you want to power through load-shedding bouts is a crucial step to take before buying a backup power solution.
This will determine the battery capacity you require, or the amount of time your backup power solution will last.
For reference, we have provided two different power demand scenarios to consider before buying an inverter trolley.
Scenario 1 — The streamer: About 150W
- 1 x 65-inch LCD TV — 120W
- 1 x smart TV box/decoder — 8W
- 1 x Wi-Fi router — 15W
- 1 x lamp with LED bulb — 8W
Scenario 2 — The gamer: About 300W
- 1 x 32-inch gaming monitor — 70W
- 1 x gaming laptop/console — 200W
- 1 x Wi-Fi router — 15W
- 2 x lamps with LED bulbs— 16W
With double the power draw, the gamer scenario’s backup battery power will last approximately half the time of the streamer.
Calculating the amount of battery capacity required is relatively straightforward and can be done by multiplying your total power draw by the number of hours you need power.
The streamer (stage 2): 150W x 2.5 hours = 375Wh
The gamer (stage 2): 300W x 2.5 hours = 750Wh
Several retailers and manufacturers often don’t specify the watt-hour capacities of their backup power systems.
Fortunately, this calculation is also relatively straightforward. Most retailers and manufacturers specify the capacity in terms of amp-hours (Ah), which can be converted to watt-hours by multiplying the Ah capacity by the battery’s voltage.
It is important to consider the depth of discharge. For lead-acid, we used 50%, and for lithium-ion, we chose 90%.
For example, the capacity of a 100Ah battery rated for 12V is calculated as follows.
For lead-acid: (100Ah x 12V) x 50% = 600Wh
For lithium-ion: (100ah x 12V) x 90% = 1,080Wh
Below, we have listed some of the cheapest inverter trolley systems and portable power stations. Lithium-ion inverter trolleys are listed below the lead-acid and gel options.