One major question every homeowner asks, when they are considering buying solar panels, is how big of a system will I need? The exact size you will need varies widely from family to family and house to house. Often, the climate you live in will dramatically affect the size of the system required.  Fortunately, the size of the solar system you will need is easy to calculate if you know how much energy you use.

To help homeowners looking to buy solar panels, we have created this simple guide.

What can a 1 kW solar panel power?

To start with it is a good idea to know what exactly 1 kW of electricity from a solar panel will power. 1 kW will be able to power:

• 60 low energy light bulbs

• 2 32” Plasma TVs

• 1 small pool pump

• Half of the power requirements of a small air conditioner

This sounds like it could be a lot, but the thing with solar is that it only hits peak power output for a few hours. This means that this 1kW system will only power this amount for 1 or two hours. So, this means you need to take into consideration how much power you will need to use at off peak times. While all solar systems are backed up by the grid, you will still want to run on your solar from time to time. You should consider this in your search.

What can determine the solar system size I need?

Different families living in different cities will have different needs out of their solar system. The climate of the are you live can have a big impact on your energy usage, especially across multiple seasons. For example, in Brisbane, a family would likely use a lot of energy from their solar panels in powering their air conditioning, and if they have a pool, a pool pump, due to the hot climate. The amount of sun your home gets will also be a major factor. It is important to look at what your solar panels will need to power, and the amount of sun your home receives before purchasing a system.

A good solar panel installer will ask for details on your energy usage in order to determine the correct size you need. This advice is paramount to ensuring you receive the best results from your solar panels, reducing your reliance on the grid.

How can I calculate the system size I will need?

It is very easy to calculate an estimate for the system size you may need. All you need to do is follow these 4 steps.

1.       Have a look at your recent electricity bill. Look at how many kWh’s you have used in the previous 4 quarters. This information will be found on your energy bill. Add up the last 4 quarters of energy usage. Now you have how many kWh’s you use per year.

2.       Now divide your annual kWh’s by 365. This will give you your daily kWh energy usage.

3.       The information below shows how many kWh’s you can expect per installed kW of solar panels based on location:

Adelaide: 4.2kWh
Alice Springs: 5.0 kWh
Brisbane: 4.2 kWh
Cairns: 4.2 kWh
Canberra: 4.3 kWh
Darwin: 4.4 kWh
Hobart: 3.5 kWh
Melbourne 3.6 kWh
Perth: 4.4 kWh
Sydney: 3.9 kWh

Now find the nearest city to you on this list and divide your daily kWh’s by this number.

4.       The number you get from that equation is the system size you need in kW.

Generally, this will give you a good estimate as to the size system you need. However, this does not mean it is the most economical solution. You may in fact need more or less depending on your home and budget.

Conclusion

The easiest way to understand what size solar system you need is to simply ask an expert. A qualified professional will be able to find you the optimal system for your home. Ensure that you do solid research on whichever solar company you choose, and make sure they are both resellers and installers. Being vigilant will help you avoid getting ripped off.