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Switching To Solar Power


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How much electricity does a solar panel produce?

Every solar panel, and solar power system, is different. So when answering questions such as how much electricity a solar panel produces, we need to consider a couple of important factors – and do a bit of quick maths. 

First things first. How do we actually work out how much electricity a solar panel produces? 

Electricity output is measured in kWh (kilowatt hours), with most panels on the market today rated to produce between around 250 to 400 watts per day. Put together, the typical capacity of a household solar system is between 1kWh and 4kWh. This means that over the course of a year, a 4 kW solar power system on an average-sized house can produce up to around 3,000 kWh of electricity per year – even taking into account sunlight hours. 

As well as the amount of sun throughout the year, the amount of electricity outputted by a solar PV system can be influenced by panel size, placement and orientation, as well as prevailing weather conditions which might impact performance on a temporary basis. 


How much electricity will my solar panels produce? 

Because there are so many differences between solar panels, we need to use a formula when working out how much electricity they will produce. Completing the calculations here will give you a rough figure for how much electricity your solar panels can produce in a day. 

To work out how much electricity your solar panels can produce: 

  • Take the square metre size of one panel, and multiply by 1,000 
  • Take the above figure and multiply it by the efficiency of your panels (as a decimal) 
  • Multiply that answer by the number of daily sunlight hours in your location 
  • Finally, divide by 1,000 

To get an estimate for the monthly total, simply do the above and multiply by 30. 

Here is an example calculation using 1.5m2 panels, with 80% efficiency and six hours of sun per day: 

1.5 x 1,000 = 1,500

1,500 x 0.8 = 300

300 x 6 = 1,800

1,800 / 1,000 = 1.8 kWh 

How much solar power do I need? 

You can work backwards from the above sums to determine what size your solar system needs to be, based on your household energy consumption. This is important to do so that you get a system capable of meeting demand. 

You don’t need to do this by yourself, though. If you’re interested in switching to solar energy, get in touch with us today, and one of our experts will help you work out the right size of system for your needs, as well as answering any questions you have about the technology and what it takes to get started.