Monday, 4 June 2012

One Year Anniversary of Solar Power.

It wasn't just her Majesty celebrating her anniversary this weekend. There were no street parties or Thames Flotillas but, our installation had it's 1st birthday. 

Just like the crowds waving their flags, I had hoped for a sunnier day, perhaps for different reasons....Nevertheless, it has proved to be a wonderful year for sunlight and green energy. 

How did the system perform?
We were predicted to produce 2,185kWh based on the government formulae used by all installers to give potential purchasers an idea on what they could earn.
I reality we achieved 2,503kWh, that's an above 14%  improvement on our expectations. 

What about fuel savings?
My wife and I finished work at approximately the same time as our system was installed in June 2011. 
I mention this as it's difficult to compare energy usage figures for 2010-11 & 2011-12 as our life style has changed completely. Previously we left the house early and returned in the evening having enjoyed our employers heating and lighting. We're now at home significantly more, which has the benefit of being able to choose the best time to use electrical appliances, but we incur additional costs to keep ourselves warm.

Total units of electricity used for 12 months 2010-11.=3,618kWh
Cost @.0918p kWh = £332.13
Total units of electricity used for 12 months 2011-12. =2,536kWh
Cost @ .112p kWh = £284.03

As you can see we've virtually generated the same amount of electricity as we've used. Wouldn't it be fantastic if technology could enable us to store that electricity and be truly self sufficient?
Despite the fact we've had lights on and heated our lounge with a low wattage electric fire during the winter months, we've actually used 30% less electricity. As one of the major reasons for installing PV panels was to try and insulate ourselves from inevitable energy price inflation, this is a huge bonus for us. We now need to try and maximise that saving by utilising our "free electricity" in the most efficient way in the future.

How green is the system?
One of the most disturbing factors of my solar experience relates to our PV panels preventing 750kg of CO2 being pumped into the atmosphere. 
Google tells me there are 25 million houses in the UK, if each of those houses saved a similar amount of CO2 then there would be 1.785 billion kg's less pollution. 
You realise the size of the problem when you consider how many cars, lorries, planes and industrial plants there are which presumably dwarf the 1.8billion kg's generated by householders....

What would I have done differently?
Hindsight is a wonderful thing. I knew even less about the component parts of a solar installation than I know now when we signed on the dotted line for our system. 
  1. I suspect the "sweet spot" for installations occurred in November/December 2011, as householders enjoyed reduced costs for PV panels whilst still benefiting from the 43.3p FiT rate.
  2. My choice of 190W panels meant that my roof space restricted me to a 2.66kWh system. Technology has improved the efficiency rates enabling recent installations to get much closer to the 4kWh limit imposed by the government.
  3. The SMA Sunny Beam monitor has generated nearly as much frustration as the system has generated electricity. I wish I hadn't listed to their technical team telling me to wipe date from the memory.
Apart from those three points I've been delighted with the whole experience.  
When I look back on the last 12 months one of the best parts has been the response from many of the visitors to the site. 
My feeble attempts to pass on my enthusiasm for the technology and experiences has been limited by the sharp learning curve of creating this site and researching subjects which relate to our mutual interests. It's kept me amused and I hope some of you have found it informative. I will try harder in the 2nd year to keep you aware of what's happening and how it may affect you.

Predicted 2011-12 income from PV panels.    £980.00
Actual 2011-12 income from PV panels.      £1,133.00

Predicted reduction in grid electricity costs.   £142.00
Actual reduction in grid electricity costs.     £121.00

Total income from installation.                   £1,254.00

Cost of installation.  £10,000.00

Return on investment.                                12.54%

I'm pleased with my results. How are you doing?

Twitter: (@solaricarus)


  1. Icarus,

    Belated conrats on your system's first birthday. May there be many such celebrations.

    I must however disagree with your comment that "I suspect the "sweet spot" for installations occurred in November/December 2011".

    IMHO the sweet spot was as close as possible to the 43.3p FiT rate deadline i.e. commissioned by the end of March 2012. That way you would have maximised your chances of benefitting from constantly reducing installation costs.

    I assessed the government's chances of winning their supreme court appeal to lower FITs and got my pv system commissioned in mid February 2012. Basically I couldn't have timed it better.

    Interestingly, it now transpires the government knew full well that their supreme court appeal stood no chance but reasoned it would would cause enough uncertainty to put a lot of people off pv installs. The sneaky b*st*rds!

  2. Hi Drambo. I agree with you 100% on your comments.
    My November/December sweet spot was based on my chronic inability to gamble. I'm a nerd.....I analyse the options endlessly. Is this going to work? Are there any obvious catches? Am I doing the right thing? All of these options were crystal clear in late 2011. I agree with you that waiting those extra months was an act of genius. However, there was SOME risk involved. The government has shown itself capable of multiple U-turns and I (in your place) wouldn't have had the bottle to play my cards that close to my chest.
    You were right and in hindsight you quite rightly will reap the rewards.
    "Viva Los Vegas"