With our abundant Aussie sunshine, big rooftops and rapidly decreasing cost of solar power systems, 10kW can be an ideal size solar system for Australian homeowners looking to maximise their electricity bill savings.
The big question is – exactly how much can you save off your electricity bills with a 10kW solar system?
The quick answer is around $2,000 to $3,000 a year, with the exact amount depending on four main factors:
- How much power your solar system generates
- How much solar power you use in your home
- What you pay for grid electricity
- How much you get paid for the solar feed-in tariff
In this article, we’ll tackle each of these topics in turn and, in the process, demystify the way in which solar electricity bill savings are calculated!
How much power your solar system generates
As a rough rule of thumb, each kilowatt of solar panels installed on your roof generates 4 kilowatt hours of electricity on average throughout the year. That means that a 10kW solar panel system will generate around 40 kilowatt hours of solar electricity on average each day.
But….this is just a general guide. The exact amount of electricity your solar panels generate depends on:
- Your geographic location
- Orientation and tilt of your solar panels
- Efficiency of your solar panels and solar inverter
- Whether there’s any shading on your panels
Geographic location
The table below shows the average daily amount of solar energy a 10kW solar system generates in Australia’s major cities, throughout the year.
Melbourne | 36 kWh |
Sydney | 39 kWh |
Adelaide | 42 kWh |
Brisbane | 42 kWh |
Canberra | 41 kWh |
Newcastle | 41 kWh |
Perth | 44 kWh |
Darwin | 46 kWh |
Hobart | 33 kWh |
It’s important to remember that this is an average. In summer you’ll be getting more than the average – and in winter you’ll get less.
It’s a good idea to get a handle on how your electricity usage varies by season; you can see this on your electricity bills. Alternatively get in touch and we can work it out for you.
Orientation and tilt of your solar panels
The direction your solar panels face can make a difference to the amount of power generated. Whilst north facing can be best, this isn’t set on stone. Matching when your household uses electricity with the direction the panels face will result in higher self-consumption of your solar power. This is the best way to save most on your electricity bills.
The tilt angle of your panels in relation to the roof is also important. The tilt should be optimised for your location and take into account any constraints posed by your roof line.
Working out the optimal panel layout and tilt for your solar system is a specialist task – every home is different. Get in touch with a Solar Run expert today for the best solar advice for your home.
Efficiency of your solar panels and solar inverter
One of the most important quality measures is solar panel efficiency –the rate at which panels convert sunlight into electricity. The best solar panels like Risen, Jinko and Sunpower all perform at the top end of the ladder at 20 per cent plus efficiency.
The same goes for the best solar inverters. You want a solar inverter that’s got a good rating for the efficiency – i.e. the rate the inverter converts DC power (direct current) to AC power (alternating current) which can be used in your home.
Solar Run only stocks leading brand solar panels and solar inverters. We can advise on the best solar panels and inverters to optimise your power generation and fit your budget.
Solar panel shading
Whilst shading will reduce the efficiency of your solar panel system, the effects of shading can be minimised with clever solar technology – like half-cut solar panels and power optimisers which maximise power generation at panel-level.
A bit of shading doesn’t mean solar is out of the question. Find out about the best solar systems to address your shading issues.
How much solar power you use in your home
The way to save the most off your electricity bill with solar is to maximise the amount of solar power you use during the daytime. You’ll get the biggest electricity bill savings if you consume most – if not all – of the solar power your 10kW solar system generates at the time when it’s being generated.
The trick is to maximise solar self-consumption and minimise the amount of solar electricity you export to the grid. Getting a good solar monitoring system will help you achieve that goal.
What you pay for grid electricity
The more you pay for grid electricity, the greater your potential bill savings with solar. That’s because when you use your own self-generated solar power in your home, you don’t need to buy the expensive electricity from the grid.
On average, Australian households pay 25-30 cent per kilowatt hour for grid electricity but this can vary widely from state to state and between retailers.
How much you get paid for the solar feed-in tariff
Solar feed-in tariffs are now worth around 7 cent per kilowatt on average in Australia. If you shop around, you may be able to do a better. But watch out that an enticing looking feed-in tariff isn’t a ploy to get you to pay more for the daily supply charge or grid power.
Generally speaking, the amount you pay for grid electricity is around 4x what you’re paid for your solar exports. Solar exports only contribute a small amount to your total bill savings. Whilst trying to get a higher feed-in rate is not a bad idea, it’s not the main way to save on your electricity bill – maximising consumption of your solar power is where it’s at!
Again, that’s where a good solar monitoring system can help.
Electricity bill savings
Here’s a worked example of the electricity bill savings you could get with a 10kW solar power system based on the following assumptions:
- Standard rate for grid electricity: 27 cents per kilowatt hour
- Solar feed-in tariff: 7 cents per kilowatt hour
- Average daily solar production based on geographic location
The bill savings are modelled for two different usage profiles:
- Household 1: uses 60% of the solar power generated in the home and exports the rest to the grid for the feed-in tariff
- Household 2: uses 40% of the solar power generated and exports the rest to the grid for the feed-in tariff
Electricity bill savings with solar – Melbourne and Sydney
Estimated total annual bill savings in year 1 | ||
Melbourne | Sydney | |
Household 1: uses 60% of solar power in their home – exports rest to the grid | $2,566 | $2,913 |
Household 2: uses 40% of solar power in their home – exports rest to grid | $2,026 | $2,300 |
This table emphasises the message that the more solar power you use during the daytime, the bigger your bill savings. It also shows that even at the lower solar consumption level of 40 per cent, the bill savings are still worth having!
Payback on a 10kW solar system
With prices for high quality 10kW solar panel systems now more affordable than ever, many of our customers are getting a payback of between 3-5 years.
As this article has demonstrated, the best payback on a solar system is when you maximise the amount of solar power used in your home – ideally getting it to 60 per cent or higher.
Having said that, even if a 10kW solar system is a bit bigger than what you need right now it could be a smart move if you’re thinking of any of the following:
- Adding battery storage in the future
- Getting an electric vehicle in the future
- Moving more of your appliances to electric’
- Extending your home in the future
- Using more electricity in the future
Talk to the experts
A 10kW solar system may be a lot less expensive than what you think. Factor in the bill savings and the future benefits and the sums may well stack up for you. Solar Run can help you with this process and we offer interest free options
Get in touch. We’ll work out whether 10kW is feasible for your roof – and accurately model the bill savings and payback of a 10kW solar system for your home.