System outperforms SAP by 19%

[dansk]

Good news today for a change! just been reported by one of my customers that the first years generation came in at 3155 versus SAP of 2552 - im please and so are they, thats an extra £261 in FiT!

Caymax 200w mono modules and Ever Solar inverter.

 

[Gavin A]

SAP really is utterly useless at predicting PV performance in most situations tbf.

good news though, and should hopefully have that customer out there spreading the word for you.

 

[FB.]

SAP really is utterly useless at predicting PV performance in most situations tbf.

good news though, and should hopefully have that customer out there spreading the word for you.

Yes, SAP compared to reality can be very much influenced by local micro climate. Coastal areas, Southern and Eastern areas, and low-lying areas often benefit from more-than-expected sun.

Not wanting to sound ungrateful, but it seems that nowadays that the SAP is a bare minimum acceptable generation target. If an installation isn't meeting SAP, there's either something wrong with the installation or design, or badly miscalculated by the salesman in the suit and posh car, or you've been very unlucky with the weather.

I reckon that SAP+10% is a more realistic "average" generation estimate.

Met Office mapped cimate averages here:
http://www.metoffice.gov.uk/climate/uk/averages/ukmapavge.html

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[dansk]

good news though, and should hopefully have that customer out there spreading the word for you.

I know SAP is lame, but it was nice to get the call after a quite week. And its more proof for the people sitting on the fence, the more good news we can generate the better it is.

 

[SolarCity]

Not wanting to sound ungrateful, but it seems that nowadays that the SAP is a bare minimum acceptable generation target. If an installation isn't meeting SAP, there's either something wrong with the installation or design, or badly miscalculated by the salesman in the suit and posh car, or you've been very unlucky with the weather.

I reckon that SAP+10% is a more realistic "average" generation estimate.

Met Office mapped cimate averages here:
Met Office: UK mapped climate averages

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Actually there are other factors. You could be off-south, yet closer to south than SE. You could have shading - yet not enough to warrant an 0.8 factor applied.

Just because the last couple of years have been good climate-wise, doesn't mean that we won't have a 800Wh per kWp next year - or less.

 

[FB.]

Actually there are other factors. You could be off-south, yet closer to south than SE. You could have shading - yet not enough to warrant an 0.8 factor applied.

Just because the last couple of years have been good climate-wise, doesn't mean that we won't have a 800Wh per kWp next year - or less.

Yes, I'm closest to SE, but actually between ESE and SE.

Regarding weather; I'd say that where I am, it has been unusually cool and dull since June last year (my trees dropped their leaves when temperatures plunged in mid-August! and we also - uniquely for this region - do not have an official drought and have seen the most bitterly cold winter in my lifetime).
So it seems as if my local area has, unusually, missed out on much of the sun in the region, due to getting more than our fair share of the region's rain.

I'm running at SAP+16% at the moment (adjusted for difference between E, ESE and SE) and I'd say that the recent weather has more or less brought the local climate back to a more normal amount of sunshine for the last several months.

 

[FB.]

Regarding the one-in-a-lifetime nasty winter here in Cambs......for several days in February, Cambridge weather records show that it was about 15'C colder than Edinburgh - both day and night!
Normally, the area just North of Cambridge is one of the warmest, sunniest and driest parts of the UK.

 

[Glen Powell]

Cooler weather, does that not give better perfomance? Spring has been very strange this year with cold morning temperatures with excellent sunshine, I think this is where the generation lies with ambient temperatures (in my area) not creeping above 17 degrees however the sun is blazing as no clouds in the sky.

 

[Eco Deal]

Had a a call this week from a old customer he submited his last quarter for FITS payments to E-on and his results where 25% higher than expected they arranged for sombody to read the meter to confirm this reading was correct !!! he had 4kwp south facing yingli and soalr edge

 

[FB.]

Cooler weather, does that not give better perfomance?

Yes, it does.
But here, we went from 19th February to 26th of March before seeing a dawn-to-dusk day of sunshine - and even when we got it, it was very hazy sunshine and my 3.75kWp panels only managed 18kWh of generation for the whole day.
In that several week period, we experienced the most fog, mist and thick cloud cover I've ever known - along with quite a lot of rain. The weather is not at all like this usually.

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[Glen Powell]

Yes, it does.
But here, we went from 19th February to 26th of March before seeing a dawn-to-dusk day of sunshine - and even when we got it, it was very hazy sunshine and my 3.75kWp panels only managed 18kWh of generation for the whole day.
In that several week period, we experienced the most fog, mist and thick cloud cover I've ever known - along with quite a lot of rain. The weather is not at all like this usually.

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Or you are only taking more notice of the weather due to the investment it holds maybe ?

 

[FB.]

Or you are only taking more notice of the weather due to the investment it holds maybe ?

No, I am very much an outdoor person - walking, cycling, gardening and growing my own organic fruit and veg. I'm well aware of what the weather is usually like as I have to judge planting of fruit and veg according to expected weather patterns which they prefer or need to avoid.
The weather data on the Met Office link also shows that East Anglia is normally hot, dry and sunny:
Met Office: UK mapped climate averages

In fact - and you'll laugh at this - we have a micro-climate.
The soil is shallow and dry. It gets very warm very quickly. It then sets up hot air currents and sucks in lots of air at ground level, causing quite a breeze - probably why we are windmill country.
This upwards airflow is enjoyed by a reasonable population of buzzards, which spend hours soaring on the hot air currents.
Even more interesting, is that these air currents have the power to push clouds aside (or cause them to fold-over or under themselves and then split sideways) as if the clouds had hit a massive glass tube; I've seen it many times, and it is normal for us to be in a sunny hole in the cloud, while areas just a few miles away get rain. Long ago my wife and I nicknamed this area "the doughnut" or "the desert" because of its unique dry/sunny/hot combination. We can easily ripen greenhouse grapes and figs outdoors, and we actually find that plants which do well in places like California or the Mediteranean also tend to do very well for us.