By the time you’re reading this, South African businesses have lived with rolling blackouts for over a decade. Most have spent something on backup power. Many spent it badly. Here’s the playbook we wish every client had read before they bought their first inverter.
The three tiers of loadshedding resilience
We sort clients into three tiers based on what they actually need to keep running during an outage. Not what they think they need — what their business actually loses when the lights go off.
Tier 1 — “Keep me on email”
Service businesses, professional practices, consultants. Email + Teams + the M365 stack must stay up. Local servers? You don’t have any. The shop is your laptop and a phone.
What works: a 1.5 kVA inverter + 2.5 kWh battery per workstation, plus an LTE failover router on a UPS. Total spend per seat: R12-R18k. That keeps a laptop, monitor, and internet alive through a full 4-hour stage 6 block with margin to spare.
Tier 2 — “Keep the office running”
Small businesses, 10-50 staff, with on-prem infrastructure that can’t move easily. Local NAS, PABX, CCTV, networked printers, point-of-sale. The office building has to stay operational for staff to work at all.
What works: a single 15-25 kVA inverter + lithium battery bank sized for 6-8 hours of office load (~30-40 kWh usable). Add a 10 kVA petrol or diesel generator for stage 6+ scenarios. Total: R350k-R800k depending on scale. Critical: get the load calculation right. The number-one mistake we see is a R200k inverter that flat-lines after 90 minutes because someone forgot the air conditioner.
Tier 3 — “We have a server room”
Mid-market with on-prem servers — typically because of legacy line-of-business apps, regulatory data-residency, or pre-cloud accounting platforms. Servers, switches, firewalls, plus cooling.
What works: the whole-building solution from tier 2, plus a properly-sized UPS feeding the rack before the inverter takes over (UPSes handle the transition cleanly; inverters often have a 20-100ms gap that crashes some hardware). Plus a load-shed plan: which servers stay up, which gracefully shut down on a battery threshold. Cooling is often the killer — a closed rack can hit 40°C in 20 minutes without forced air.
The cloud-first answer most businesses miss
For most mid-market businesses we audit, the cheapest loadshedding strategy isn’t more batteries. It’s moving the server room to the cloud.
A R600k on-prem refresh plus R400k of backup power is often replaceable with M365 Business Premium + Azure Files + a properly-configured Intune deployment, for around R1 800 per user per month. The local infrastructure that needed protecting goes away. Loadshedding becomes a connectivity problem, not a power one.
And connectivity is solved cheaply: a fibre primary + LTE failover for under R3k/month per site, with Cape Town, Durban, and Johannesburg data centres reachable in under 20ms regardless of what Eskom is doing.
What most businesses get wrong: forgetting the comms
The single most common loadshedding mistake we find on audit: backup power that keeps the servers running but ignores the network gear. The ONT (fibre terminal) is plugged into a wall socket. The firewall is on a desktop strip. The Wi-Fi APs are PoE-fed from a switch in a closet without a UPS.
The servers are technically alive. Nobody can reach them. The business may as well be off.
Rule we use: if you can’t keep email running, you can’t bill. So everything in the path between “user types email” and “the recipient receives it” must be on backup power. ONT, router, switch, Wi-Fi, modem if you still have one. Not just the servers.
A worked example
A 30-person Polokwane logistics company we audited last year. Stage 6 hit, they took a 4-hour outage during peak booking time. Lost productivity: ~120 person-hours at an average loaded cost of R280/hr = R33 600 in wages alone. Missed bookings (estimated): R45 000. Direct loss: just under R80 000 for one afternoon.
The fix we recommended cost R420k installed and amortised over 5 years works out to R7 000/month. After one bad stage in any given month, it’s already paid for itself.
If you’re not sure which tier you’re in, or whether your existing setup will actually survive a stage 6 day, book a free 60-minute IT health check. We’ll look at the load, the gear you’ve got, and tell you straight whether you need to spend more — or stop spending.