5kW Solar Power Systems
For an average Australian family home a 5kW solar power system is a relatively large system and should easily supply enough electricity. If you have a 5kW system and its not big enough then your home is using way above the Australian average kWh domestic consumption rate.
If you are looking at installing a solar power system with deep cycle batteries, or wish to add batteries at some point in the future then a 5kW system is the minimum size you should choose.
How many solar panels in a 5kW system?
At 250W per solar panel a 5kW system will need 20 solar panels. At 1.6m x 1m for each solar panel a minimum of 32m² of roof or mounting area will be needed. The image below can give an idea of the relative area of a 5kW solar array:
Below is what a 5kW solar panel array looks like mounted on a tin roof.
How much power can a 5kW solar power system produce?
The expected output from a 5kW solar PV system is about 20kWh per day, on average an Australian home uses 16-18kWh every day. However most residents are out during the day when the sun is shining and solar energy is being produced by the system, so installing a 5kW system does not automatically mean you will never pay for power again. If your a night shift worker then it maybe a different story. This is the current conundrum with solar PV systems and one of the main drivers behind the recent innovations, hype and tech race in the home energy storage market.
How much money can I save with a 5kW solar power system?
The price paid to grid connect solar system owners for exporting power into the grid in most parts of Australia is about 8c per kWh, to buy power from the grid the cost is close to 30c per kWh. So its not just about how much power you generate Vs how much you use, when you use it will effect the outcome of the solar saving equation, see possible outcomes below:
1. When the sun is shining and your panels are producing electricity you use 100% of that power and don't export any, this is unlikely however not impossible. If that were the case you would save $2,150 in the first 12 months and $67,100 over the next 20 years with inflation at 5%.
2. You export half of the power from your solar system and use the other half yourself, you would then save $1,400 in the first 12 months.
3. You sell back to the grid 100% of the power from your system, this would give a saving of $700 in the first year.
How much does a 5kW solar power system cost?
In today's money you are looking at $10,000 before STC's. The STC (or solar rebate) will give you about $3,500 so that's a total of $6,500 total system cost.
How long for a 5kW solar power system to pay for itself?
If you use all the power from the system instead of buying it from the grid, a 5kW system should pay for itself in 5 years. If you get finance for the system and the amount you save on your monthly power bill is more that the monthly payment of the loan then your in front from day one! just make sure the solar panels don't blow away in a storm uninsured.
Best advice with buying and installing a 5kW solar system:
1. Use a good Solar Payback Calculator to help you find a system kW size that's right for you and what you expect from solar.
2. Get at least 3 Solar Quotes from accredited solar panel installers.