How to choose a generator

From portable to standby, and all the way up to industrial, there’s a very wide range of generators available to buy. When choosing, it’s important to work out exactly how you want to use your new machine, so you can narrow down your list of potential purchases.

Size matters

Choose a generator that’s too small for your needs and you might find yourself caught short, if you want to power up bigger items, like freezers, or other essential items during an outage. 

Choose a generator that’s too big and it may end up costing you more than you bargained for. The bigger the generator, the more you’ll spend on fuel, maintenance and repairs when required. Plus, you’ll face a bigger financial outlay at the start and also be sitting on all this extra capacity that you’ll never need.

On your list make sure you have at least three generators, so that you end up buying the one that’s ‘just right’ for you.

What wattage will you need?

There’s a quick way to work out the optimum wattage for your new generator. Imagine all the different items that you would ever want to power simultaneously. Refer to each product’s operator manual or website, then add up all the running (sometimes called rated) watts for these products.

While you’re looking, also make a note of all the starting watts. Once you’ve discovered the single highest starting watts figure, from the whole list, add that number to your total running watts. You’ll need to buy a generator that can produce this many total watts, so it can start and keep powering all of your items.


Be prepared

There’s always a surge in generator purchases after a heavy storm. If you live in an area, with historical power outages, it might be worth considering buying a generator before you’re left in the dark. If it’s essential that you have continuous power, no matter what, it’s definitely worth investing in a generator before the event.

How to choose a generator

Other things to weigh up

Obviously, buying a generator is a big purchase and you’ll want to get it right first time. Some portable generators can be quite cumbersome to carry around, so it’s worth noting how much each of them weigh, to see if you need help setting them up.

It’s also worth thinking about the decibel (dBA) rating if you’ll be using the generator in residential or holiday areas. Fuel is another major consideration. If you’re powering up multiple machines, over a long period of time, look at generators with the largest fuel capacities.

Another consideration is around open and closed frame generators. Both of these types of generator provide quieter, cleaner power compared to a traditional generator, but each comes with its own pros and cons. Open frame generators are noisier but easier to access and maintain, whereas closed frame generators are quieter and have casings that protect the machinery from external factors like the elements and dirt. They are also slightly more expensive than open frame generators.

Inverter generators use an advanced AC/DC current conversion method that makes them smaller, lighter and quieter than standard generators. They also offer better fuel efficiency and improved run time per litre than petrol generators. However, conventional portable generators are cheaper than inverter generators.

New generation

If you still need help deciding on the best generator for your needs look at our wide range of generators or speak to one of our helpful team.

Health & Safety

Please make sure you use all equipment appropriately and safely when following the advice in these D.I.Y. videos. You need to be familiar with how to use equipment safely and follow the instructions that came with the equipment. If you are unsure, you may feel it is safest to consult an expert, such as the manufacturer or an expert Bunnings Team Member.

Grave health hazards are linked to asbestos, which may be in homes built up to 1990. Health hazards may result from exposure to lead-based paints in older materials and copper chromium arsenic (CCA) treated timber. For information on the dangers of asbestos, lead-based paint and CCA treated timber and tips for dealing with these materials contact your local council's Environmental Health Officer or visit our Health & Safety page. You can also use a simple test kit from Bunnings to indicate the presence of lead-based paint.
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