Fri, 07 Aug 2026 20:27:22 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=41426#Comment_41426 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=41426#Comment_41426 Sun, 21 Dec 2008 15:17:14 +0000 GBP-Keith
hotelrefurber,
1. I cannot give averges other than what you can see in this thread:
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=2342&page=1#Item_9

until a year has elapsed.

2. To replace my batteries with secondhand forklift batteries (the most common choice for offgridders) would probably cost about £4000. However, i believe that providing i can keep my generation higher than my demand my batteries will have an almost unlimited lifespan. batteries seem to die when they constantly kept close to discharged. I expect mine to just act as buffers.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=45934#Comment_45934 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=45934#Comment_45934 Tue, 03 Feb 2009 17:19:16 +0000 GBP-Keith https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=45935#Comment_45935 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=45935#Comment_45935 Tue, 03 Feb 2009 17:23:16 +0000 GBP-Keith https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=56373#Comment_56373 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=56373#Comment_56373 Tue, 23 Jun 2009 15:14:29 +0100 GBP-Keith

Yields are explained quite well here: http://lightbucket.wordpress.com/2009/03/10/rooftop-solar-power-in-the-uk-–-real-world-data/

"The “yield” of a photovoltaic system is the amount of energy it produces in a year divided by the rated peak capacity. The units of yield are usually kilowatt-hours per kilowatt-peak. This quantity is just another way of expressing the ratio of mean power-to-peak power.

Yields on the domestic PV systems in the field trial varied from below 400 kWh/kWp to over 900 kWh/kWp, but the largest number of sites was in the yield range 701–800 kWh/kWp. This range of yields is equivalent to a mean power-to-peak power ratio of 8.0%–9.1%, about what you’d expect for UK insolation levels."]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60028#Comment_60028 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60028#Comment_60028 Wed, 12 Aug 2009 08:00:20 +0100 SimonH
Have you got any upadted figures for this lovely "summer" we're having? I was wondering if it means outputs are 10%, 50% or 90% lower than usual!

I'm currently putting together a proposal for a series of community owned PV plants, so would like to get some min/max figures dependent on weather. Currently using an assumed 750kWh/year per peak KW.

Cheers,

Simon.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60035#Comment_60035 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60035#Comment_60035 Wed, 12 Aug 2009 09:17:10 +0100 billt http://re.jrc.ec.europa.eu/pvgis/.

That should to give you a good idea of the output of your proposed system.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60056#Comment_60056 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60056#Comment_60056 Wed, 12 Aug 2009 12:09:31 +0100 stephendv 1 with a mechanical tracker AND an MPPT charge controller
1 with a static array and a non-MPPT charge controller

There is a third option, that many people go for, and which is quite cost effective, which is static array with MPPT charge controller.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60062#Comment_60062 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60062#Comment_60062 Wed, 12 Aug 2009 13:12:32 +0100 GBP-Keith
stwephendv's point is partly valid though. no one should install a system without mppt.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60101#Comment_60101 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60101#Comment_60101 Wed, 12 Aug 2009 21:50:37 +0100 scott especially with uk limited sun conditions and short number of hours
as used in most all big solar parks
expensive to buy though
can get them as small as to 300watts to take 1x300Wp modules or 2x150Wp]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60145#Comment_60145 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60145#Comment_60145 Thu, 13 Aug 2009 14:57:52 +0100 stephendv The vast majority of solar parks are static, not tracked.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60196#Comment_60196 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60196#Comment_60196 Thu, 13 Aug 2009 22:42:40 +0100 Terry https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60223#Comment_60223 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60223#Comment_60223 Fri, 14 Aug 2009 10:07:01 +0100 fostertom http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4420&page=1#Item_23 there's discussion about exactly why we should try to turn glass-fronted solar panels, PV or wet, perp to the sun's rays - there 2 separate reasons as far as I can see - and how much tolerance there is in that, for practical purposes.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60253#Comment_60253 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60253#Comment_60253 Fri, 14 Aug 2009 16:13:38 +0100 stephendv https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60344#Comment_60344 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=60344#Comment_60344 Sun, 16 Aug 2009 18:23:00 +0100 GBP-Keith https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=137615#Comment_137615 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=137615#Comment_137615 Thu, 01 Mar 2012 12:15:34 +0000 SteveZ
These are the results from the first full month (Feb 2012) of operation of my 4kWp PV array. It is arranged on two orientations. 3kW (12 panels) due East and 1kW (4 panels) due South, located just East of Bodmin Moor in Cornwall. I am interested to see how it compares with any similar 'conventional' inverter array as I have a system using on-panel Max Power Point Tracking, rather than that being done by the Inverter. In theory , it could give better power production, although there are slightly bigger losses in the circuitry.

Is a total of 166kWh good, bad or indifferent for this array in the South West UK?

BTW the difference in performance between the East and South sections is very marked at this time of year. As an example from one sunny day, East produced 2.1Kwh per 1kWp and the South 3.7Kwh per 1Kwp. I hope the sunrise moving towards the NE as the year progresses will bring the performance of the East section back to the theoretical 85% of a due South array.

Date Energy (Wh)
01/02/12 7880
02/02/12 9473
03/02/12 9480
04/02/12 1034
05/02/12 5654
06/02/12 2664
07/02/12 9419
08/02/12 9973
09/02/12 8983
10/02/12 841
11/02/12 8057
12/02/12 3354
13/02/12 4076
14/02/12 4781
15/02/12 2926
16/02/12 5045
17/02/12 4425
18/02/12 3784
19/02/12 8068
20/02/12 7983
21/02/12 5432
22/02/12 1889
23/02/12 4895
24/02/12 3149
25/02/12 5781
26/02/12 10664
27/02/12 3589
28/02/12 2866
29/02/12 10291
Total Wh 166454
Total kWh 166]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140396#Comment_140396 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140396#Comment_140396 Thu, 22 Mar 2012 14:12:44 +0000 Triassic
If I were to construct my own system how easy would it be? Doing a Google suggest that there is loads of kit available, but which is the best and most robust?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140435#Comment_140435 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140435#Comment_140435 Thu, 22 Mar 2012 18:39:40 +0000 cbatjesmond Posted By: SteveZIs a total of 166kWh good, bad or indifferent for this array in the South West UK?
Can plug www.bdpv.com again? They provide a way of sharing PV production data and seeing others' production. The nearest site to you appears to be http://bdpv.com/fiche_utilisateur_en.php?util=iain

When you compare two systems it automatically scales to kWh/kWp, which is v.convenient.

To provide a direct answer: 166kWh seems good to me, but my 1.72kWp system only produced 68kWh in February ... at 55N.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140444#Comment_140444 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1672&Focus=140444#Comment_140444 Thu, 22 Mar 2012 19:32:46 +0000 SteamyTea ]]>