Load shedding is not simply an inconvenience for South African businesses. It is a recurring physical stress event for every piece of active network equipment on your premises. Repeated power interruptions degrade batteries, accelerate capacitor wear, and expose sensitive electronics to the voltage transients that occur on grid restoration. Understanding these failure mechanisms is the first step to preventing them.
Even though South Africa experienced a significant reduction in load shedding frequency in 2024 and into 2025, the underlying grid infrastructure remains under strain and unplanned outages continue. A protection strategy built during calmer periods is worth far more than emergency repairs during peak shedding seasons.
The Scale of Load Shedding Damage to Telecoms
The numbers behind South Africa's 2023 load shedding season make the case for infrastructure protection better than any theoretical argument. According to CSIR analysis, South Africa experienced load shedding across 287 days in 2023, shedding a total of 6,950 hours of power and 25,000 gigawatt-hours of electricity from the national grid. That figure represented the worst load shedding year on record at the time.
The economic consequences were severe at every scale. The SA Reserve Bank estimated GDP losses of up to R899 million per day during peak Stage 6 load shedding events. Engineering News reported that the year was described by industry observers as an "annus horribilis" for infrastructure-dependent sectors, with telecommunications operators bearing a disproportionate share of the damage.
In response, South African telecoms operators collectively invested R3.5 billion in backup power systems in 2023 alone. That capital went primarily into diesel generators, lithium-iron-phosphate (LiFePO4) battery banks, and remote monitoring systems for base stations and exchange facilities. The investment reflected a hard-learned lesson: connectivity infrastructure that is not actively protected against power interruption will fail.
For individual businesses, the lesson is the same at a smaller scale. The cost of a UPS and surge protection kit is measured in hundreds to a few thousand rand. The cost of a failed Optical Network Terminal (ONT), damaged switch, or corrupted router configuration is measured in days of downtime and replacement hardware costs.
How Power Outages Damage Network Equipment
Load shedding causes three distinct types of hardware damage, and each requires a different protection approach.
Voltage spikes on power restoration. When Eskom restores grid power after a shedding cycle, the reconnection event introduces a voltage transient onto the supply line. This spike, which can exceed 1,500 volts in differential mode under the IEC 60664-1 standard, lasts only microseconds but carries enough energy to destroy the switching power supplies inside routers, ONTs, and managed switches. Equipment that survives one or two events may accumulate incremental damage that causes premature failure months later.
Battery degradation from frequent cycling. UPS units and any equipment with internal rechargeable batteries suffer accelerated degradation when charge-discharge cycles occur multiple times per day. A standard valve-regulated lead-acid (VRLA) battery rated for 200 cycles at full depth of discharge will exhaust that rating in under four months during Stage 4 load shedding conditions. LiFePO4 chemistry handles deep cycling significantly better, with cycle ratings above 2,000 for quality cells.
Surge damage to ONTs and switches. Optical Network Terminals are particularly vulnerable because they sit at the interface between the fiber network (which carries no electrical current) and the powered internal network. The ONT's power supply and Ethernet interfaces are exposed to any transient that enters via the mains supply. Unprotected ONTs are among the most commonly replaced items following storm events and grid restoration incidents across South Africa.
SANS 61643-11, the South African national standard governing surge protective devices (SPDs) for low-voltage power installations, provides the technical framework for protecting equipment from exactly these transients. Compliance with this standard is the benchmark CT Communications uses when specifying protection for any customer installation.
UPS Solutions for Fiber ONT and Router Equipment
Selecting the right UPS for home office or small business fiber equipment starts with understanding the actual power draw. A typical fiber ONT consuming 8 to 12 watts combined with a mid-range Wi-Fi router drawing 10 to 18 watts places total equipment demand at under 30 watts in most residential and small office configurations. This is a modest load that even entry-level UPS units handle comfortably.
The practical decision points are runtime, battery chemistry, and the quality of the surge protection circuit built into the unit. The table below covers the three tiers most commonly installed in South African homes and small offices.
| UPS Tier | Typical Price (ZAR) | Battery | Rated Runtime at 30W | Best For |
|---|---|---|---|---|
| Entry-level (sealed lead-acid, 600VA) | R700 to R1,000 | VRLA 7Ah | 2 to 3 hours | Stage 2 to 4, occasional cycling |
| Mid-range (LiFePO4, 8,800 to 12,000 mAh) | R1,600 to R2,200 | LiFePO4 | 4 to 6 hours | Daily cycling, Stage 4 to 6 |
| Rack-mount (LiFePO4, 100Ah+) | R8,000 to R20,000 | LiFePO4 | 24 hours and above | Server rooms, multi-device racks |
Entry-level units from under R1,000 are sufficient for a single ONT and router combination through a standard two-hour load shedding block. However, their VRLA batteries are not designed for the multiple daily cycles that extended shedding seasons demand. Replacement battery costs (typically R250 to R400 every 12 to 18 months under heavy cycling) should be factored into the total cost of ownership.
Mid-range LiFePO4 units in the R1,900 range, such as the 8,800mAh to 12,000mAh units available from local electronics retailers, offer significantly longer cycle life and handle four to six hours of runtime at the typical ONT-plus-router load. For most South African households and small offices, this tier represents the best balance between cost and durability.
For installations protecting network switches, IP cameras, VoIP adapters, and multiple access points in addition to the ONT and router, calculate total connected load before specifying a UPS. As a rule of thumb, select a unit rated for at least twice your calculated load to allow for startup surge current and to preserve battery longevity by avoiding full discharge on every cycle.
Surge Protection Standards for South African Installations
Surge protection for telecoms equipment in South Africa is governed by three primary standards that work together to define what adequate protection looks like.
SANS 61643-11 (equivalent to IEC 61643-11) covers surge protective devices connected to low-voltage power distribution systems. It defines test waveforms, protection levels, and installation requirements. Type 1 SPDs are installed at the main distribution board to handle direct and indirect lightning surges. Type 2 SPDs are fitted at sub-distribution boards or socket outlets to provide secondary protection for connected equipment. Most quality surge-protected power strips sold in South Africa are Type 3 devices providing equipment-level protection. A compliant installation typically uses Type 1 and Type 2 devices in combination, with Type 3 strip-level protection as the final layer.
SANS 10142-1, the South African Wiring Code, requires that all new electrical installations include surge protection at the main distribution board. Properties built or rewired after the relevant edition came into force should already have this first layer of protection in place, but older commercial buildings frequently do not.
IEC 60664-1 establishes insulation coordination requirements for equipment in low-voltage systems, including the 1,500-volt differential mode surge level that equipment power supplies must be able to withstand. When a power supply is not rated to this level and no external SPD is installed, grid restoration transients can exceed the equipment's design limits.
One practical point for any installer specifying metal-oxide varistor (MOV) based SPDs: SANS 61643-11 requires that MOV devices include a thermal fuse or thermal disconnection mechanism. An MOV without this protection can overheat and catch fire when it absorbs a large surge. Always verify that any SPD carries a thermal fuse notation before installation.
What Changed in 2024 and 2025
After the record-breaking 2023 load shedding season, South Africa experienced a dramatic reversal. Load shedding occurred on only 69 days in 2024, almost entirely concentrated in the January to March window. From April 2024 onward, the country entered a ten-month period free of scheduled load shedding, driven by improved Eskom plant availability and increased contributions from independent power producers.
Load shedding returned briefly in January 2025, though at lower stages than the 2023 peaks. Eskom's published projections, reported by the Daily Investor among others, indicated no planned load shedding through to March 2026, pointing to continued improvement in generation capacity.
The reduced frequency of outages does not, however, reduce the case for infrastructure protection. Several points are worth keeping in mind. First, the improvement is in planned load shedding frequency, not in the underlying grid stability. Unplanned outages, fault trips, and weather-related interruptions continue regardless of the load shedding schedule. Second, a single voltage spike on power restoration can destroy unprotected equipment regardless of how infrequent the outage that caused it.
Third, and most practically: protection equipment installed during a quieter period does not go to waste. A LiFePO4 UPS installed today provides value as backup power, as surge protection, and as a safeguard against the unplanned outages that occur on every grid, not only South Africa's. The question is not whether to install protection, but when.
Building a Resilient Telecoms Infrastructure
A complete protection strategy for business network equipment combines three elements: backup power for all active devices, surge protection on every entry point, and contingency planning for extended outages beyond UPS battery capacity.
- Install a correctly rated UPS on every active network device, including the ONT, router, managed switches, and any VoIP adapters
- Fit Type 1 and Type 2 compliant SPDs at the distribution board to intercept large transients before they reach equipment
- Add Type 3 surge-protected power strips at the equipment level as a final protection layer
- For facilities that cannot afford even brief outages, integrate a generator with an automatic transfer switch rated for continuous operation
- Schedule annual inspection of UPS battery condition and SPD thermal fuse integrity
CT Communications provides power resilience assessments for commercial properties across Gauteng. Our engineering team evaluates your current installation against SANS 61643-11 and SANS 10142-1 requirements, identifies unprotected equipment, and specifies the most cost-effective combination of UPS and surge protection for your load profile.
"The most expensive load shedding protection is the replacement hardware you buy after the first unprotected outage. A correctly specified UPS and SPD combination costs a fraction of a single ONT or managed switch replacement."
Frequently Asked Questions
Will a standard surge-protected power strip protect my router from load shedding damage?
A surge-protected power strip provides Type 3 SPD protection at the equipment level, which is the final layer of a compliant three-tier installation. It will reduce damage from moderate voltage transients but is not designed to absorb large surges from direct or nearby lightning strikes. For full SANS 61643-11 compliance, Type 1 protection at the main distribution board and Type 2 protection at the sub-board are required in addition to the strip-level device.
How long will a mid-range UPS keep my fiber internet running during a two-hour load shedding block?
A mid-range LiFePO4 UPS with a capacity of 8,800 to 12,000 mAh can power a typical ONT and router combination drawing under 30 watts for four to six hours. Most two-hour Stage 4 blocks fall well within this capacity. Runtime is reduced if you add additional devices such as IP phones, network switches, or security cameras to the same UPS, so calculate your total connected load before purchasing.
Is load shedding less of a risk in 2025 and 2026 compared to 2023?
Scheduled load shedding was significantly less frequent in 2024 and into 2025, with Eskom projecting no planned shedding through March 2026. However, unplanned outages from fault trips and network faults continue, and the voltage transients generated on power restoration are identical regardless of whether the outage was planned or not. Protection equipment remains relevant and cost-effective regardless of the current load shedding stage.
Need a Power Resilience Assessment?
CT Communications evaluates your network infrastructure against SANS 61643-11 requirements and specifies the right UPS and surge protection combination for your premises. Contact our engineering team for a no-obligation consultation.
Sources and References
- CSIR, Load Shedding Statistics, Council for Scientific and Industrial Research. csir.co.za
- Engineering News, "Graphics confirm 2023 as loadshedding's annus horribilis," November 2023. engineeringnews.co.za
- Engineering News, "Telcos feeling pressure of sustained levels of loadshedding," February 2023. engineeringnews.co.za
- ISS Africa, "Communication blackout: impact of power grid collapse on ICT." issafrica.org
- Daily Investor, "Eskom's load shedding miracle shown in one graph." dailyinvestor.com
- Atomic ISP, "Fibre during load shedding." atomic.co.za
- Fibre Tiger, "Internet load shedding options: buy this, not that." fibretiger.co.za
- News24, "The cheapest and easiest way to keep your internet up during load shedding," March 2023. news24.com
- SAFEhouse Association, Surge Protection Guide. safehousesa.co.za
- Lightning King, "Understanding SANS standards: lightning protection standards in South Africa." lightningking.co.za
- LSP Global, "Are surge protection devices mandatory?" lsp.global
- Wikipedia, "South African energy crisis." wikipedia.org
