I just run some stats test on our weekly grid variation, If you look at demand and compare it to hours of daylight and temperature there is no significant difference, shame you cant get the effects of 2GB of PV out of the data.

Was looking at the demand variations over the last three years to see if grid supplied was significantly down in the summer. Trouble is that demand is down just because it is warmer. And down because we have greater hours of daylight. And we are in a recession. Also at 1 twentieth of our summer demand it is on the limit of significance testing. Shame as it would be useful to know as we could work out a useful price for solar then.

Yes, and I was just interested to see if there was a difference in grid demand because of the extra distributed generation, but the NG 5 minute data is too crude. May be possible at the lowest level to spot a difference, but probably not at the town level. I suspect that there is not much demand shifting in houses with PV fitted this time of year. Every house I went to when I worked for a PV company tended to use electricity during the day anyway. One customer even told me how 'useless' and expensive E7 was. I pointed out that she had her 300lt hot water cylinder on all the time and she was using separate electric showers instead of using the hot water she had already paid for. She also did her washing in the mornings so she could 'get it on the line before noon to get the afternoon sun'.
Would be interesting to see how many people have demand shifted and stuck to it. Not everyone is like us.

Not such a silly way to test it. Shall have a look, think it is a while off for the UK.

9:30 on the 20th March 2015 (close to equinox) will be the day, shall we take a punt on the weather

See you there, I usually use a wielding mask

Alright, had my lenses changed for nice clear acrylic ones with no UV filtering, can see all sorts of things now.
I used the black glass one that I used for arc wielding, probably why I needed my cataracts done, along with growing up in the tropics, working with sunbeds and then a UV curing plastic.

https://www.gov.uk/government/statistical-data-sets/weekly-solar-pv-installation-and-capacity-based-on-registration-date

Total installed capacity 451,476 kWp

Said it before I think, the trends look too similar for my liking.

Still looks dodgy to me

The thing that worries me about the DECC data is that there seems to be a very linear relationship between both the number of installation or the installed capacity of installation.
If I run a Student T-Test on their numbers with the hypothesis that the numbers are right, with the null hypothesis that they are wrong (fudged if you like) then you get a p-Values of between 0.0000015922 and 0.0000000002. As this is less than 0.05 for all 3 installations sizes, then I conclude that the numbers are wrong (fudged).
It is possible clearer if charted, looks like a mirror image and a bit of y-axis translation.

Well it show that for every MW of 0-4 kWp installed there is a close relationship to the other two banding. They hardly vary at all.
About 50-65:1 a year ago and now 47-57:1

The Student T-Test is all about checking means and how much a mean can vary within bounds (so is quite good for this sort of analysis).

Somehow I just don't think that for say every 1MW of domestic PV there is somewhere between 0.016 and 0.02 MW of commercial.
I would have expected a non linear relationship with the domestic de-accelerating and the commercial accelerating. There is a slight acceleration on the bigger stuff, but not statistically significant.
Tempted to e-mail them to get clarification.

The point I am making is that, and you can see it on the charts, for any given week the fraction of 4-10 kW and 10-50 kW when compared to the 0-4kW is consistent. So if domestic installs go up, then the other 2 do, if domestic installs go down, the others go down.
Does that not strike you as odd?
Why should these very different markets be linked in this way?
Is there any reason why sales/installs in the domestic market should have any influence on the smaller commercial market.
I know that some domestic installers can fit a 4 kW system in half a day, but I don't know of any 50 kW systems fitted as quick.
Just seems a bit odd that all systems installed and all installed capacity tracks each other so well.

The tarrif change causing a spike is not that much of a surprise on the domestic side, but on the larger stuff I find it is. Not as if a 50 kW project is sold and fitted in a few days. These are much longer projects usually and the FITs review is done at short notice (though at least we now know when it is).

Conegy have gone into receivership. That should help stabilise prices. Going to call DECC on Monday and ask more about the figures.

The output of the Solar farm at Hoo is reported weekly, this is a 999 panel installation with a capacity of 249.75kWp. Since the project has been Crowdfunded the top weekly output was 11,082 KWh during the week 29/04/13 - 05/05/13. The last couple of weeks with extra hours and extra heat have been around 10,000 kWh - https://www.abundancegeneration.com/projects/#!/42048/updates