Thu, 25 Jun 2026 04:15:12 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164451#Comment_164451 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164451#Comment_164451 Mon, 07 Jan 2013 10:05:24 +0000 sarahhughes thanks
Sarah]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164452#Comment_164452 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164452#Comment_164452 Mon, 07 Jan 2013 10:16:39 +0000 jamesingram http://pvoutput.org/help.html#overview see what system in your local area have been up to.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164453#Comment_164453 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164453#Comment_164453 Mon, 07 Jan 2013 10:21:44 +0000 Beau I can give accurate figures in a couple of months time as that's when 2 years is up on one of the systems here but it does not look good and it's not if we had a decent year in the south west in 2011. Gut feeling is we need to be prepared for many more years like this one and be grateful if we have a long term average year. We did see the sun for a few hours on New years day but not been seen since. I looked at some local weather data and it has rained on average 3 out of 4 days here since May this does not prove it's been cloudy but it's a good indication of what it's been like.

Beau from a miserable dank and cloudy Dartmoor.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164455#Comment_164455 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164455#Comment_164455 Mon, 07 Jan 2013 11:06:20 +0000 SteamyTea Posted By: BeauBeau from a miserable dank and cloudy Dartmoor.Sun is out here, from Cornwall ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164459#Comment_164459 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164459#Comment_164459 Mon, 07 Jan 2013 12:22:15 +0000 billt
For 2012 the output is 4.6% above the PVGIS classic estimate but 6% below the PVGIS climate-SAF estimate. For us production hasn't been much lower than expected.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164464#Comment_164464 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164464#Comment_164464 Mon, 07 Jan 2013 12:52:05 +0000 Beau ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164467#Comment_164467 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164467#Comment_164467 Mon, 07 Jan 2013 12:55:26 +0000 SteamyTea Clouded over now ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164472#Comment_164472 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164472#Comment_164472 Mon, 07 Jan 2013 13:40:18 +0000 skyewright 2012 generation 3141kWh (118% of PVGIS climate-SAF with 14% system losses)

N.B. We were the corner of the UK where it was very wet while the rest was building up to a drought, then dry when if started raining everywhere else (I've had a rain gauge since the start of 2008, in 2012 March to October, inclusive, all had below average rainfall).]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164481#Comment_164481 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164481#Comment_164481 Mon, 07 Jan 2013 18:54:21 +0000 SteamyTea https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164483#Comment_164483 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164483#Comment_164483 Mon, 07 Jan 2013 19:31:09 +0000 Jeff B
Apr 2011to Dec 2011 = 2530 kWh
Apr 2012 to Dec 2012 = 2437 kWh

So, surprisingly, little difference actually (down about 100 kWh).

If I assume that the coming Jan, Feb and March figures are the same as last year, then the totals for the 2 years would be:

Apr 2011 to Mar 2012 = 2969 kWh
Apr 2012 to Mar 2013 = 2876 kWh

So again about 100 kWh down.

Now, if anyone had asked me this question, the "off the top of my head answer" without checking the figures would have been that we were significantly down on last year, not because of the rain so much (we've not had it so bad as some parts) but just the number of overcast days. When the sun appears lately it is an immediate talking point. I wouldn't be surprised to see a resurgence of rickets amongst children down in these parts (west Pembs)!

I should add that ours is a 3.9 kWp system.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164484#Comment_164484 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164484#Comment_164484 Mon, 07 Jan 2013 19:40:33 +0000 cbatjesmond
2010 generation 1243kWh
2011 generation 1326kWh
2012 generation 1234kWh

2012 went wrong for me just after I boasted on GBF about having had the best Dec2011/Jan/Feb/March2012 in three years: I then got the worst April-July which should be the bulk of the years' generation :-/]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164488#Comment_164488 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164488#Comment_164488 Mon, 07 Jan 2013 20:14:29 +0000 jamesingram https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164494#Comment_164494 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164494#Comment_164494 Mon, 07 Jan 2013 21:02:20 +0000 SteamyTea So we may have had 'less sunshine' but mean figures are pretty stable.
Probably a different story with solar thermal, anyone got figures for that?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164501#Comment_164501 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164501#Comment_164501 Mon, 07 Jan 2013 21:53:59 +0000 Beau https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164502#Comment_164502 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164502#Comment_164502 Mon, 07 Jan 2013 22:07:10 +0000 SteamyTea https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164503#Comment_164503 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164503#Comment_164503 Mon, 07 Jan 2013 22:09:38 +0000 Beau ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164504#Comment_164504 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164504#Comment_164504 Mon, 07 Jan 2013 22:23:28 +0000 SteamyTea https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164508#Comment_164508 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164508#Comment_164508 Mon, 07 Jan 2013 22:40:34 +0000 Gotanewlife ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164518#Comment_164518 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164518#Comment_164518 Tue, 08 Jan 2013 08:22:55 +0000 CWatters https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164521#Comment_164521 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164521#Comment_164521 Tue, 08 Jan 2013 09:18:23 +0000 sarahhughes https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164522#Comment_164522 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164522#Comment_164522 Tue, 08 Jan 2013 09:20:02 +0000 skyewright Posted By: SteamyTeaWas that compared to the long term average or the 2008 to 2012 average?
My own rainfall data only goes back to 2008, so it's a highly localised 2008 to 2012 average I'm commenting on.

The Met Office used to have nice charts for this sort of thing, but I can't find them on the new style website. The pages that seem to be the equivalent of what I'm after don't show data after 2010, but I could easily be missing something obvious.

Assecondary evidence that the effect applied to NW Scotland more generally, you might be interested to know that the water authority had to tanker in water to some places...]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164523#Comment_164523 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164523#Comment_164523 Tue, 08 Jan 2013 09:22:03 +0000 billt
Still, this year's going to be nice and sunny to compensate!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164604#Comment_164604 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164604#Comment_164604 Wed, 09 Jan 2013 09:30:58 +0000 Seret https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164612#Comment_164612 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164612#Comment_164612 Wed, 09 Jan 2013 10:23:11 +0000 SteamyTea https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164614#Comment_164614 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164614#Comment_164614 Wed, 09 Jan 2013 10:51:56 +0000 Mikel
For Camborne the average annual sun hours are 1638 hrs for the last 31 years and 1643 annual hours average since 2000. The sun hours for the year to October 2012 are 1385 hrs (data come from Met Office web site). So it appears we have had about 85% of the average annual sunshine in this neck of the woods.

Not surprising that the figures are on the low side.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164621#Comment_164621 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164621#Comment_164621 Wed, 09 Jan 2013 11:24:57 +0000 SteamyTea Posted By: MikelFor Camborne the average annual sun hours areIs that just hours of sunshine or clear sky?
I can't seem to track it down on the Met Office website today.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164653#Comment_164653 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164653#Comment_164653 Wed, 09 Jan 2013 16:35:36 +0000 Mikel
http://www.metoffice.gov.uk/climate/uk/stationdata/cambornedata.txt]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164774#Comment_164774 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164774#Comment_164774 Fri, 11 Jan 2013 10:49:08 +0000 Mikel
Down here, most of those sun hours were in the first half of the month. Our PV production for December was 85% of the PVGIS-Classic estimate.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164823#Comment_164823 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9966&Focus=164823#Comment_164823 Fri, 11 Jan 2013 20:35:43 +0000 Gavin_A Posted By: SteamyTeaPVGIS tends to be a bit cautious, about 5% less on the kWh, not sure now they have updated the model data.
obviously depending on what losses you use - the 14% standard figure is very conservative. We mostly use somewhere between 7-10% losses for unshaded systems depending on fairly precise inverter & cable loss figures, and it's proving remarkably accurate once you factor in solar input levels (approximated from the local met office stations sunshine hours stats).]]>