Relying on the power grid at all times is convenient and easy. Until it isn’t. If you’ve been in an extended power outage you’ll know how hard it is to go without power. With increasing severe weather and an energy crisis on the east coast, more and more Australian’s are considering backup power to the family home. So, ‘Can a generator power a whole house?’ Here are the answers you need to know.
Can a generator power a whole house?
The answer is yes a generator can power a whole house! But it depends on the size of your household power requirements and the wattage of your generator. In this blog post, we’ll give you a breakdown of how much power a typical Australian home uses and what size generator and type of generator you’ll need to power it. So, if you’re looking for backup power during a blackout for your entire house, read on for all the information you need!
Why consider a home generator
In Australia, we mostly get our power from large power plants that might be using black and brown coal, natural gas powered generation or renewable energy like solar power, hydro or wind. When our power systems are operating (which is most of the time) they generate electricity and provide it to our homes and we don’t have to worry about a thing!
But Australia’s electricity supply is more and more often disrupted by extreme weather events and natural disasters. Just ask the national electricity market operator, whose job it is to restore our power systems when large scale blackouts occur. They’re already looking into ways to make our power grid more resilient to increasing natural disasters.
With a future of more intense and frequent weather events, Australian’s are increasingly thinking about adding a backup power supply to power appliances at their home, in case of emergencies.
Using a home generator for backup power
A home generator can take on electricity generation and run the electrical circuits in your house in case of a power failure, so that things like refrigerators and freezers, phones or pumps are kept going until the power is restored.
Generators come in a wide array of different configurations, sizes and types, with capacities ranging in from around 2kW (portable generators) to 20kW or larger (standby generators).
Many Australians have a diesel generator installed as a backup energy source when the grid goes down. You can also get a gas home generator to power your home.
How can a generator power a whole house?
A right sized generator is one that meets your household power needs.
If a home generator is too small, it will not be able to handle the load of the entire house. Additionally, if the home uses more power than the generator can provide, then the generator will not be able to power the whole house.
But the good news is, a generator can power a whole house if it is big enough to provide the amount of power that your home uses! To answer this question for your own home, there are two things to work out:
- How much peak (kW) and running (kWh) power your house uses
- What size home generator you need to provide power that meets your whole house needs
We’re going to look at these down below.
How much power does a typical Australian home use?
A typical Australian home uses a considerable amount of power. A typical home might use between 9 and 10 kilowatts of power demand daily.
9 to 10kW of power demand is the home’s ‘peak demand’ for energy at any point during the day. It’s when a typical home needs the most power at any one time, because of the different types of appliances the home is running all at once.
It’s not the total energy the home uses each day to power everything all day.
‘Peak demand’ kilowatts can stack up easily. 10kW is reached by just running 5 appliances all a once – a fridge (0.8kW), a TV (0.4kW), an electric hot water system (4.5kW), a cooktop (1.5kW) and an aircon/heat pump (3.6kW).
But some larger households can use up to 20kW if they are running multiple appliances with high energy requirements (like a hot water system or air conditioner), all at once.
You may also find smaller households only really need 5kW to 7kW of power to run their whole house.
Purchasing a home generator that is right for you
Before you purchase a home generator you need to know:
- What size generator you need
- What fuel source you need
- What type of generator you need (knowing the size you need will help you here)
Let’s look at each of these.
What size home generator will power your appliances?
To work this out, lets look at your daily peak demand for power, as well as your daily power usage.
Why peak power requirements are important
Your daily peak power requirement is important to determine your generator size, if you’re powering a whole house.
At the same time as providing power supply to run your appliances, your generator needs sufficient ‘peak power’ to cover an initial surge in power demand when an appliance is turned on.
This initial power demand to start up the appliance is called ‘starting watts’ – you can read more about this below.
Conversely, the power an appliance needs to run continuously throughout the day is called its ‘running watts’.
Starting watts are higher than running watts in some appliances!
Starting watts contribute heavily to your peak power requirements – the largest amount of power you use at any one time of the day.
If you want to run a whole house, you need to a generator size (‘peak power’ output) that will cover your peak power requirements.
Your generator’s ‘peak power output’ should be larger than your daily ‘peak power requirements’.
You’ll find a generators peak output rating in the technical specs for the unit.
How to work out your household ‘starting watts’ and ‘peak demand’
Let’s start with writing down a list of all of the appliances in your home (including lights), as well as their starting watts and their running watts. Don’t forget mobile devices and plug in equipment!
Think about everything on that list that you will run at the one time.
Then, for these items, add up their running watts. If an appliance has a starting watts number, write it down too.
Total up all of your running watts. Add to this the highest starting watt number on your list.
Now you know (in watts) your peak power requirement for everything in your house that you plan to operate at the one time!
You can use this information to choose a home generator with a peak power output (capacity) that is big enough to meet your peak power requirement.
Your total running watts will tell you the ‘rated output’ you need from a home generator, to power your home continuously.
If you want to know more about where to find and how to calculate your starting and running watts, read our Generator sizing guide. And check out our Generator sizing calculator, which comes with a wattage guide for household appliances. It’s free!
Always oversize your generator a little in terms of it’s peak output and rated output. This will give you more flexibility to operate things like heating and cooling. These types of appliances have large starting wattages and require a lot more peak capacity from your generator to start them up.
What type of fuel should your home generator run on?
Diesel generators are popular in Australia, but you can also purchase large generators that run your whole house using natural gas as their energy source. Let’s have a look at some pros and cons.
Diesel versus petrol generators
Diesel generators have long been the preferred choice for those in need of a reliable and powerful backup generator in Australia.
Diesel generators are typically more expensive than petrol generators, but they offer a number of advantages that make them worth the investment.
Diesel generators are more fuel-efficient than petrol generators, meaning they can run for longer periods of time without needing to be refuelled.
Diesel generators also tend to be more durable and require less maintenance than petrol generators. As a result, diesel generators are often the best choice for those who need a generator that will be used frequently or for extended periods of time.
Diesel versus natural gas generators
You can also choose natural or bottled LPG as an energy source, and buy a gas generator. If you have natural gas to your home, this may be an option.
Gas generators typically run more quietly than diesel generators. They are also smaller and less bulky or heavy than diesel units. However, their lifespan is shorter and gas is highly flammable so there is a greater fire risk with gas powered generators.
Gas generators also use more fuel to operate, so are less fuel efficient than diesel generators and will cost in gas more to run. Gas generators will generally cost more to maintain too, due to the use of spark plugs and wires in the design of the unit.
Solar generators
Solar generators are growing in popularity fast in Australia. A solar generator is a solar PV system connected to a battery storage system.
Solar generators are free to run (the sun is your fuel source), but generally more expensive to buy.
One of the main hurdles to purchasing a solar battery generator is the price. But with the cost of battery production reducing, prices are coming down and the popularity of this option is increasing.
The benefits of solar generators is that they don’t make any noise, generator clean power, don’t require lots of maintenance, and have minimal running costs. You do need to make sure the battery is charged when you need it. And the life of the battery is around 10 years for a Lithium Ion model.
What type of generator you need
Portable generators versus standby generators
Portable generators are not generally wired into your home. Instead, you locate them outside your home and use power cords to plug devices directly into the generator. This means that portable generators are generally not used to run equipment that is hard wired into your power board. For example, your oven, hot water system, or lighting circuits. You could plug your fridge or lamps directly into a portable generator however.
Portable generators are a great option for people who need temporary power. Because they are not wired in to your power board, they are easy to set up and can be used for a variety of purposes, from powering tools to providing emergency backup power. However, portable generators have limitations.
They are typically less powerful than standby generators, and they require regular maintenance. In addition, portable generators must be more regularly refilled with fuel.
Standby generators are a more permanent solution for people who need backup power. They are permanently installed and connect directly to your home’s electrical system. They can power anything in your home, depending on how you have them wired by an electrician.
Standby generators are more expensive than portable generators, but they offer a longer-term solution and larger power capability (to run more appliances). They may be a good option if you experience extended power outages due to extreme weather events or poor grid reliability in your area.
If you are looking to power your whole house, a standby generator is probably your most likely option.
You can find portable generators and standby generators that use different fuel types – from diesel, to gas, to lithium ion batteries.
Inverter generators – clean power
The kind of generator you need for your home may vary according to the type of electrical appliances that you use.
Generators can provide power that is sometimes called ‘dirty power’. Dirty power is power that has lower reliability. It can fluctuate as it runs.
Several electronic devices like TV’s, computers or phones can be affected by fluctuating energy supply. If you’re using a generator for these devices, you need to use the most efficient and clean kind without power surges or spikes, so it will not damage the machine.
There are two options.
You can use an inverter generator to power your house with clean power.
Or you can add an automatic voltage regulator to a larger standby generator, to clean up its power output. An automatic voltage regulator is a device that your license electrician can install along with your generator.
When choosing your generator, look at the price difference between these options and see what’s best for you.
If you want to know more on this topic, have a read of our epic post about what type of generator you need to run a house.
Using a generator
Home generators are a great way to provide backup power in the event of a power outage. However, it is important to follow some basic safety precautions when using a home generator. One of the most important things to do is to install a transfer switch.
A transfer switch is installed between your home’s electrical panel and the main power supply. It allows you to safely connect your home generator to your power board.
When the generator is running, the transfer switch will direct power from the generator to your home’s electrical panel. This will provide power to your home’s circuits, keeping your lights on and appliances running.
But when the generator is turned off, the transfer switch will disconnect the generator from your home’s electrical system. It works in reverse when the power grid is down. This ‘switching’ prevents backfeeding, which can damage your home’s electrical panel and pose a fire hazard.
So if you want to use a home generator, be sure to have a transfer switch installed first.
When using your home generator, always make sure to keep it in a well-ventilated area to avoid carbon monoxide buildup, and never operate it indoors. Due to electrical shocks and electrocution, a generator requires proper maintenance to ensure the proper operation of your equipment.
Following these simple tips will help you safely enjoy the benefits of having a home generator.
Installing a generator
Generators, voltage regulators and transfer switches must be installed by a qualified electrician, and instructions can also be found in the home generator’s manual. Once the transfer switch is installed, you should test it regularly to make sure it is working properly.
Conclusion
In this post, we’ve answer the question ‘Can a generator power a whole house?‘ The answer is yes, a generator can power a whole house. In Australia, a small house might need a generator that provide around 7,000 watts (7.5kW) of power. A typical Australian household might need something that can provide 10,000 watts (10kW) of power. A large house may need a generator that is 20kW or more. Generators go up in prices as they do in size so running a whole house will be expensive. For a more affordable option, it’s best to customise your generator size to run only those appliances you really need in a black out.
