Are you thinking about getting a generator? This is what you need to know

With load shedding top of mind (although we wish it was out of mind), more and more consumers will be looking at alternative methods of power. One of these is a generator, and we turned to an expert in generator installation to provide us with clarity when it comes to making this purchase.

Q. What is the difference between a generator and an inverter?

A generator runs on diesel or petrol and an inverter runs on battery power.

Q. What are volts?

The standard unit used to measure how strongly an electrical current is sent around an electrical system.

Q. What is kVA? How much kVA is required to run a household?

KVA stands for kilo volt ampere and is a unit of apparent power which is electrical power (unit 1 kilovolt ampere = 1 000 volt ampere). You need a minimum of 7.5 kVA to run a three-bedroom house excluding the geysers; including one geyser requires 10 kVA and two geysers require 15 kVA.

7.5 kVA air-cooled key start generator mounted on castors with handles

Q. What is three phase and is every generator three phase?

Single-phase is a single alternating current through a single wire, whereas a three-phase system is a three-wire system carrying an alternating current with a definitive time offset in-between the voltage waves.

Q. Is there a difference between diesel and petrol generators?

For home use, petrol generators are more cost-effective and more silent than diesel generators but you get better fuel efficiency from your diesel generator.

Q. What would you recommend based on the following?

• A small budget: A 5 to 7.5 kVA single-phase petrol generator with the estimated cost of plug and play R12 500; installed with a manual changeover R19 500 with a running time of four to five hours on a 24 litre tank.
• Complex living: You could use a battery inverter of 2400 watt (2.4kVA) which includes two light DSTVs, fibre and TV running time of four to five hours at a cost of R13 500 (all prices excl. VAT).
• Noise and air pollution concerns: Air-cooled engines are generally quite noisy and the best way to dampen the noise is a wooden box but it must be ventilated in the front, back and top. Petrol and diesel generators that are noisy emit carbon dioxide into the atmosphere but can run continuously as long as the tank is full, whereas an inverter is completely silent but will only run for the four-to-five hour period if the battery is fully charged. Batteries generally need to be replaced every three years. 

Q. How do the sizes of generators work?

They are measured in kVA or Kilowatts.

Q. What size is best to run an entire household, inside and out?

A 15 kVA will comfortably run a three-bedroom household with one geyser, but this is excluding the swimming pool pump R34 385 installation with a 12-metre cable and manual change overestimated at R14 500 subject to site inspection (prices incl. VAT).

Q. What size is best to run just the lights, gates, TVs, fridges and simple appliances things like bottle warmers and toasters?

Definitely no appliances with an element, but a 7.5 kVA is sufficient at R13 500 for installation subject to site inspection.

Q. Is it easy for a woman to start a generator while holding a baby in the other arm?

There is an option between a key start which is manual and an automatic changeover switch which will start the generator up automatically. As long as it’s a key start generator or has been professionally installed with a safety manual changeover switch, you will manage.

Q. Are lots of smoke and noise produced, and do I need an open space or can it be installed in my garage?

Open-air is preferable as it does need ventilation. If it is to be placed in a garage, we can provide an exhaust extension that can be installed to expel the fumes.

Q. What can you do to reduce or mask the fumes?

We can provide a customised exhaust with a muffler, but it won’t reduce the fumes.

Q. My neighbours complain about the noise of generators in the area. Is there a bylaw that limits generator installation and noise?

Only 55 dBA (decibel chart) is allowed for residential use.

Q. How do you get one of those really big generators into a property? Do I have to breakdown my wall or can we use a crane?

This would be a water-cooled diesel generator in a sound-attenuated canopy (20 to 25 kVA weighs about 450 kg) and is placed on site with a crane truck.

“Only 55 dBA (decibel chart) is allowed for residential use.”

Q. What is the lifespan of a home generator and how often must it be serviced?

Air-cooled must be serviced every 50 hours. Water-cooled generators must have their first service at 50 hours and thereafter every 200 to 250 hours, or annually.

Q. Can you programme your generator from an app on your phone?

Yes. A have a water-cooled diesel generator with a suitable controller can be used off your mobile.

Q. Does it need lots of cables and how can these be protected or prevented from becoming a hazard?

Cabling is laid under the ground with white sand filling or cable racks are utilised for vertical cable installation.

Q. Does a generator have a cage around it – can I put one?

That is an option for safety, but it’s not a standard feature.

Q. Are there slots and grooves where children can insert their fingers or toys, making it a safety hazard?

It is a hazard for children and it is marked with caution stickers. I would recommend a cage to be installed if you have young children.

Generator installed in a cage

Q. Do they come with safety precautions for customers?

Part of our commissioning process includes safety precautions.

Q. Can generators be covered under household insurance?

Absolutely, and when installed by an electrician a certificate of compliance is issued.