Our first year solar PV stats are now in

celerity

I now have a full year of solar stats.

Location: Cambridge, UK
System: 3.91kWp / Sunnyboy 4000 inverter
Azimuth: approx -15

Our installer estimated 3354kWh for the first year, and this was the figure I based my decision on. Subsequent knowledge of PVGIS gives me a figure more like 3190kWh, but this is possibly because I have input some figures incorrectly, so I'm still using 3354kWh as my target.

Our actual generation was 4403kWh, which I'm treating as about 31% above predicted levels.

Obviously, we are very chuffed indeed. It will be interesting to see if future years come in below estimated levels to average out our generation.

Given system degradation, I'm expecting this past year to be a record .

/\dam

Cardew

No wonder a drought has been declared for your region!

Given there is a finite sum for FITs, if your results - about £500 more in FIT than predicted - are replicated across the UK, I wonder what effect that will have on the rate-setting of future FITs?

celerity

Actually I think we are in a tiny oasis of non-hosepipe-ban territory.

I'd imagine overperforming systems will reduce the rate - but surely that is showing that the FiT has built in flexibility?

As an aside, I don't see many people on here posting that their panels are underperforming to predicted levels (ignoring shading issues), in fact, quite the contrary. So either the past 18 months or so has been unusually good for solar PV, or minimum stated efficiencies of panels are somewhat pessimistic nowadays. If the latter is the case then that makes the argument for solar PV in the UK more compelling.

I'd like to make it clear that I'm not jumping to any firm conclusions based on one year of stats though.

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Cardew

celerity wrote: »

So either the past 18 months or so has been unusually good for solar PV, or minimum stated efficiencies of panels are somewhat pessimistic nowadays. If the latter is the case then that makes the argument for solar PV in the UK more compelling.

Conversely that the level of FIT was, and is, set far too high.

Martyn1981

celerity wrote: »

I now have a full year of solar stats.

Location: Cambridge, UK
System: 3.91kWp / Sunnyboy 4000 inverter
Azimuth: approx -15

Our installer estimated 3354kWh for the first year, and this was the figure I based my decision on. Subsequent knowledge of PVGIS gives me a figure more like 3190kWh, but this is possibly because I have input some figures incorrectly, so I'm still using 3354kWh as my target.

Our actual generation was 4403kWh, which I'm treating as about 31% above predicted levels.

/\dam

Bet you're chuffed Adam.

Checking PVGIS, I get about 3,200 on classic, but 3,600 using climate, so either way some big generation. Using Cardiff, purely for comparison, I see 3,350 and 3,550, so a smaller variance.

Can't really back this up, too many numbers bouncing around in my head from this years posts, but I'm getting a gut feeling from all the north of London posters, that it's possibly a favourable place to be for PV. Less clouds on average, or pure statistical luck?

Have fun.

Mart.

celerity

Cardew wrote: »

Conversely that the level of FIT was, and is, set far too high.

I don't agree I'm afraid. I personally wouldn't have invested in my system if the FiT had been much lower and if enough people felt the same as me, the solar PV economy in the UK wouldn't have been kickstarted in the way that it has.

This is all speculation of course. I'm sure you will maintain that the current price drops of PV systems would have still been seen without the FiT. For my part I don't think they would have.

No real way of changing the other person's mind though .

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celerity

Martyn1981 wrote: »

Can't really back this up, too many numbers bouncing around in my head from this years posts, but I'm getting a gut feeling from all the north of London posters, that it's possibly a favourable place to be for PV. Less clouds on average, or pure statistical luck?

Yeah, it's going to be interesting to revisit this in say, five years time. There will be a huge amount of statistical data from the FiT which will make the efficiency of PV in the UK much clearer.

And without wishing to tempt fate, at some point we are going to start seeing a flurry of "My inverter had failed!" posts on these forums...

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rogerblack

celerity wrote: »

And without wishing to tempt fate, at some point we are going to start seeing a flurry of "My inverter had failed!" posts on these forums...

As inverter technology matures, costs will come down.

There are already driver chips appearing to do most of the work in an inverter, and greatly simplify its design.
While it's probably not unrealistic to say a fair number of inverters will be failing in 10 years time - it's probably also fair to say they're going to be a lot cheaper.

celerity

rogerblack wrote: »

While it's probably not unrealistic to say a fair number of inverters will be failing in 10 years time - it's probably also fair to say they're going to be a lot cheaper.

They'd work out even cheaper if they could somehow harness the schadenfreude that would be generated by solar PV detractors in the face of mass inverter failures .

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The_Green_Hornet

rogerblack wrote: »

While it's probably not unrealistic to say a fair number of inverters will be failing in 10 years time - it's probably also fair to say they're going to be a lot cheaper.

I would say that it is very unrealistic unless you believe that a fair number of inverters are going to break down irrevocably the day after the guarantee runs out.

Inverters (SMA ones anyway) are designed to last for over 20 years.

rogerblack

The_Green_Hornet wrote: »

I would say that it is very unrealistic unless you believe that a fair number of inverters are going to break down irrevocably the day after the guarantee runs out.

Inverters (SMA ones anyway) are designed to last for over 20 years.

I hesitate to have much faith in 20 year guarantees where essentially every component in the device is a new design in the last 5 years or so.

Especially where such devices are often in hot environments, and connected to the dirty spiky mains handling power.