Load shedding and your jumping castle: powering the blower

A jumping castle needs constant power — the blower runs the entire time it’s up. Cut the power and the castle sags within a minute, kids and all. In load-shedding South Africa, that makes backup power part of the job. Here’s how to keep bouncing.

Why it matters

The moment the blower stops, the castle starts deflating. That’s both a safety issue — you need to get children off before the walls go soft — and a party-ruiner. For a rental operator, a booking cut short by load shedding is a refund and a bad review.

Step one: know the schedule

Before every booking, check the load-shedding schedule for the venue’s area (not yours) and the stage for that day. If a slot falls during the party, either plan around it or bring backup power. Never assume — schedules and stages change.

Sizing a generator (the important bit)

The mistake everyone makes is sizing a generator off the blower’s running watts. You must size off starting watts — the surge when the motor kicks on, which is two to three times the running figure.

• A 1.1 kW blower draws about 1 100 running watts but roughly 2 000–2 200 starting watts.
• Rule of thumb: allow about 2.0–2.4 kVA per blower — that covers the surge plus headroom so the voltage doesn’t sag.
• So a single-blower castle wants a ~2.5 kVA generator minimum; two blowers (big units) want around 4–5 kVA.
• A petrol inverter generator is quieter and cleaner for a party — and carry enough fuel for the whole hire.

Not sure of your blower’s rating? Our blower guide covers the kW/HP for each castle size.

Generator safety

• Run it outdoors, well away from people — never in a garage, tent or enclosed space (carbon monoxide is deadly and invisible).
• Keep fuel sealed and away from children and the generator’s hot exhaust.
• Protect the extension lead and keep it clear of running feet and water.

What about a battery or home inverter?

Most home inverters and UPS units can’t handle a blower’s continuous draw plus its start-up surge for the length of a party — they’re built for lights and electronics, not a motor running for hours. For reliable castle power, a correctly sized generator is the practical answer.

If the power goes and you have no backup

Stay calm, get every child off while the castle is still firm, then switch off at the wall so the blower doesn’t surge back on unexpectedly when power returns. Wait it out or pack up.