Solar Panel Output - Shortest Day Behind Us!

With the shortest day now behind us we can start to look forward to improving solar panel outputs over the next few months. After the first year with our solar panels it was obvious how much lower the electricity output from solar panels is over the winter months.


Solar Panel Output - Shortest Day Behind Us!

While you may get a solid 16 hours generation during the summer months this can drop to around 6 hours or less during winter especially on very cloudy days. Last year on an extremely cloudy day we barely generated any electricity and on one snowy day had a 0 kWh output.

Luckily even with the poor summer of 2012 we still achieved over 20kWh of electricity generation on 4 days and over 15kWh on 55 days.

In contrast December had no days over 10kWh and only 8 days when above 5kWh was produced.

You can view the full yearly & monthly solar panel output statistics here

Is Solar Panel Investment Still Worthwhile?

Are solar panels still worth buying as an investment or has the sun set on solar power?

We got our solar PV panels last year just before the FIT (Feed In Tariff) was cut from 45p to 21p. At the time it was a great investment and the speculation has been that the investment is no longer worth it. However in that time the price of solar panels has plummeted again so the investment may still be a good one.

I thought it would be useful to compare the numbers we obtained from our first years generation and run them through the calculations for a solar panels based on the new FIT rates and the current price for solar panels.

We paid £9000 for our 3kWp panels and get a FIT rate of 47p per kWh. These generated 3250kWh which produced an income of £1527

Latest panels look to be available for under £6000 for 4kWp panels and on a roof with the same direction as our 3kWp, should be expected to produce 4333kWh of electricity per year. The FIT income from this would be £693 at the 16p rate.

The payback period for our panels is just under 6 years, but the payback for a new installation at the lower FIT rate would still only be just over 8 years so in many ways still a very attractive investment.

When FIT was first introduced the price of solar panels was £16,000 or more for 4kWp so the price drop has meant that the lower FIT retains the same benefits as those at the time Feed in Tariffs were introduced.

What is Annual UK Solar Panel Output from Domestic Installation?

What is the UK Solar Panel Output per year?

We have now had our solar panels for over 12 months so are starting to get year on year comparisons of the output.

Our first year we generated 3095 kWh of electricity from our 3kWp panels (14x Sungrid 245W) but this would have been around 3250 kWh without a loss of 2 weeks generation in August 2012. This is substantially above the SAP2009 estimate of 2479kWh for a 3kWp system.

You can see this graph of Solar Panel Output in the UK which shows the peak at the middle of the day and how the output from solar panels drops towards the end of the day.


What is the UK Solar Panel Output per day?

View UK Solar Panel Output details here