What is the maximum electricity my solar panels will generate?
For our panels which are virtually south facing in South East England the electricity output generated equates to around 7kWh per kWp per day. So for 3kWp of solar panels you would get a maximum of 21kWh of electricity on the best sunny days of the year and for 4kWp of solar panels you would get 28kWh.
A sunny day during winter would only generate a maximum of 7kWh of solar electricity so you can see the difference that the longer days make. Temperature has an impact and less electricity is generated from solar panels on hot days than cooler days.
The difference between the best day in winter and the best day in summer is around 3x. So in winter we would get 7kWh from our solar panels but in summer could get a maximum output of 21kWh.
Do solar panels generate only on sunny days?
No. PV Solar panels will generate on cloudy days and do not just need sun shining on them. However the amount of electricity generated on a cloudy day is a fraction of that generated in the sun. In the winter this can be as low as 5% of the amount for a sunny day. In the summer a cloudy day may generate as much as 10% and even on a day with mixed cloud and sunny spells you can get as much as 50% of the output of a clear sunny day. A day with a mix of sunshine and cloud can generate some of the biggest peaks of output as a result of the solar panels cooling down when the cloud passes over.
What output will my solar panels give?
The output of your solar panels will depend on a number of factors such as the direction they face, the angle of your roof, your location in the country and if they are affected by shading. The output is significantly higher during summer months and can be around 3x higher than the maximum obtained during winter.
What direction should my solar panels face?
In the UK the best output from solar panels will be achieved if they are south facing.
What is the difference in generation between sunny and cloudy days?
The amount of electricity generated on a cloudy day is a fraction of that generated on a sunny day. In the winter this can be as low as 5% of the amount for a sunny day. In the summer a cloudy day may generate as much as 10% and even on a day with mixed cloud and sunny spells you can get as much as 50% of the output of a clear sunny day.
How can I make the most of the electricity generated by my solar panels?
A member of MoneySavingExpert has created circuit diagrams for a device to monitor the output from PV Solar panels and to enable households to use the maximum output from their solar panels. You can view the information on Dave Fowler's website here
Solar Panel electricity generation questions and answers