Solar: how much you paid (£) how much you have generated (kWh) and date of install.

cepheus

I was unaware that the solar panels were themselves subsidised, so you need to add a thousand quid for installations. This should feed through to solar prices next year, although I disagree this should have been applied to all energy saving products.

http://www.carbonzerorenewables.co.uk/blog/2015/06/885/thinking-of-solar-panels-act-now-to-beat-a-15-hike-in-vat

EricMears

cepheus wrote: »

I was unaware that the solar panels were themselves subsidised, so you need to add a thousand quid for installations. This should feed through to solar prices next year, although I disagree this should have been applied to all energy saving products.

http://www.carbonzerorenewables.co.uk/blog/2015/06/885/thinking-of-solar-panels-act-now-to-beat-a-15-hike-in-vat

So was I - and I still don't consider that applying a lower rate of vat counts as a 'subsidy'.

Electricity bills (along with gas, heating oil etc) are charged at 5% and that seems the appropriate rate for generating equipment. I've never heard of electricity bills being described as 'subsidised' because of that lower rate. And are we also to describe newspapers, books, most food and children's clothes (all zero rating examples) as subsidised ?

But even if the vat rate does go up, the present 'typical price' of £5000 already includes a vat charge of 5% so would only increase by £700ish and there will very likely be further reductions in price between now & then.

theboylard

cepheus wrote: »

I was unaware that the solar panels were themselves subsidised, so you need to add a thousand quid for installations. This should feed through to solar prices next year, although I disagree this should have been applied to all energy saving products.

http://www.carbonzerorenewables.co.uk/blog/2015/06/885/thinking-of-solar-panels-act-now-to-beat-a-15-hike-in-vat

[STRIKE]1. Only if the the gubment actually drop the argument with the EU.
It is likely that they'll just change the classification under which they granted the reduced VAT rate.
2. If the VAT was applied at 20% instead of 5%, I don't think the prices will go back up - more likely we won't see the big falls in costs we've seen to date so the average install of around the £5k mark for a 4kW system will remain.
[/STRIKE]

*Edit* Eric said it much better!!!

zeupater

Made a post so similar to Eric's (but more verbose!) that I deleted it ...

Z

Martyn1981

cepheus wrote: »

I was unaware that the solar panels were themselves subsidised, so you need to add a thousand quid for installations.

Then you should stop complaining about PV posts, and start reading them instead:

Martyn1981 wrote: »

Household generation and energy saving materials could lose 5% VAT status:

Domestic solar facing 15% VAT hike following EU ruling

cepheus wrote: »

This should feed through to solar prices next year,

Could you provide support for that statement?

Are you also aware (or not) that due to the ongoing PV price dispute with China, that Chinese PV in Europe has a minimum price attached to it, making it more expensive at the moment than PV in South East Asia. Would you also like to account for this potential future price drop?


More important than these theoretical issues, can I ask if you are happy with the 8.56p/kWh cost of generation that I came out at using your (rather cheeky) cost figures?

Mart.

cepheus

Martyn1981 wrote: »

Yep, I got the same 2,810kWh. So he appears to have increased the cost by 20%, decreased generation by 26%, charged £2,500 for replacement inverters, added £437 for cleaning, and another £250 for insurance ....... before concluding that the earnings don't cover costs?

[Edit: Whilst still rather extreme, shouldn't the replacement inverter costs be £1,500 not £2,500? £1k for replacement at yr10 to yr20, and half the cost of replacement at yr20 to yr25.

Something else has now occurred to me. If we use cepheus' figures, with the £1,500 inverter costs (£6k + £1.5k + £437 (cleaning) + £250 (ins)) the total is £8,187.50. Then divide that by his generation figure of 25 x 3825kWh (2.62*365*4) = 8.56p/kWh. A figure not far off my 7.3p and within my range of 7p to 9p, whilst being absolutely nowhere near his 15p figure.

I accept that I haven't included degradation, but inflation should push up the value part faster than degradation lowers the generation part. M.]

I'm not sure the 5 month wait for this information was worth it! :sad:

Mart.

I haven't increased anything. I've just averaged the results of the kWh actually generated. These are real results from the source you gave me. Can't you see the formula in the spreadsheet?

Yes obviously if everyone had a 4 kW system in ideal conditions you would generate more electricity, in which case they may be exporting more to the grid at the lower price. Some people may not have the roof space, or shading or could use enough electricity during the day to justify a larger system. I've left the price of a 3.13 kW system out to avoid argument.

Bear in mind also these are just those who have reported, and are presumably relatively successful, they don't include include the cases as I've included earlier to provide balance.

All the quotes are sourced and I have halved the cleaning cost.

Martyn1981

cepheus wrote: »

I haven't increased anything. I've just averaged the results of the kWh actually generated. These are real results from the source you gave me. Can't you see the formula in the spreadsheet?

[Note: I'm using your post, and your numbers.]

You stated quite clearly a kWh/kWp figure of 956.3 :-

cepheus wrote: »

Thats reasonably consistent with the few people who have supplied data on here. The average return is around 2.62 Kwh/day/Kw.

However, your stated income figure, at an average of 10p is:

cepheus wrote: »

The return from saved plus exported electricity is £7026 over 25 years

£7026 divided by 10p = 70,260kWh which is 2,810kWh pa, or 702.6kWh/kWp. So as I stated, you've reduced the generation by 26.5%.

You also stated a price of £6k

cepheus wrote: »

so I've assumed the PV panels add 4% (£6000 of a 150k rebuild)

So as I stated you've increased the price by 20% compared to what people can pay now.

Your cleaning bill is a joke.

You also overstate the cost of the inverters:

cepheus wrote: »

I've entered the default cost of inverters as £1000 per ten years,

&

The return from saved plus exported electricity is £7026 over 25 years, just enough to cover the cost of the panels. However, if the cost of inverters, cleaning and insurance is allowed for the return is £3839 over this period.

£7026 - £3,839 = £3,187

If your cleaning costs are £35 x 12.5 times = £437.50

Your insurance costs are £10 x 25 = £250

£3,187 - (£437 + £250) = £2,500

That means you've added £2.5k for replacement inverters. However, if you replaced one at year 10, and applied half the cost of the replacement at yr 20, then the real figure should be £1.5k.

So you've overstated the costs massively.


As I've shown, using your numbers (which I believe are still too high in costs, and too low in generation, when looking for the first domestic systems to go subsidy free) the cost of a kWh of leccy is 8.56p.

8.56p is close to the numbers I've been giving you for months, but is simply miles away from your unsupported 15p/kWh figure.

Mart.

zeupater

cepheus wrote: »

I haven't increased anything. I've just averaged the results of the kWh actually generated. These are real results from the source you gave me. Can't you see the formula in the spreadsheet?

Yes obviously if everyone had a 4 kW system in ideal conditions you would generate more electricity, in which case they may be exporting more to the grid at the lower price. Some people may not have the roof space, or shading or could use enough electricity during the day to justify a larger system. I've left the price of a 3.13 kW system out to avoid argument.

Bear in mind also these are just those who have reported, and are presumably relatively successful, they don't include include the cases as I've included earlier to provide balance.

All the quotes are sourced and I have halved the cleaning cost.

Hi

Then there's no need to calculate the figures based on the generation of a system considerably smaller than 4kWp, whilst applying the price of a system which is considerably greater than what you'd expect to pay for a 4kWp system ....

What needs to be considered is that you are attempting to convey what the position would be for anyone looking to make a decision, in which the only relevant data is what's currently available and normally done. Although you've used older systems in order to account for any degradation, you seem to have fallen into the inevitable 'investment trap' ... five/six years ago a 4kWp system cost around £20k and therefore the average install capacity was, in many cases, limited more by investment than roof-space .... This is well supported by looking at the effect of the smaller systems in the data sub-set which you've used, which includes a high proportion of small systems down to just over 1kWp (TGH, a member has a 1.13kWp system which is probably in the data subset) .... The average size of UK installations on the site from which your data was sourced is 4.146kWp ( http://pvoutput.org/country.jsp ) which suggests that using 4kWp isn't unreasonable .... alternatively you could analyse the average size of recent installations from the DECC FiT statistics which are continually being published ( https://www.gov.uk/government/collections/feed-in-tariff-statistics#monthly ) ...

Regarding ... "Bear in mind also these are just those who have reported, and are presumably relatively successful, they don't include include the cases as I've included earlier to provide balance." ... I really don't understand the logic behind what you're trying to say here ... Simply looking at the systems on the PvOutput database shows the range of performance which is being reported. The figure (kWh/kWp/day) you have calculated and used is actually higher than the average which the entire UK data subset suggests, so sub-optimal reporting is definitely already included ... also, when someone starts to monitor their own system against that of others, how would they know that their systems are 'relatively successful' or not ... then there's the 'cases' which you've included which are purely related to 'rip' off prices, which is irrelevant when simply looking at the generation cost ....

As it stands, you seem to have discredited your own original claim related to the cost/kWh discussions and, even though employing tactics to massage data, are now providing figures which are broadly in-line with what (almost) everyone else has been pointing out for a considerable time, whilst employing alternative presentation formats which so-obviously attempt to disguise the error in that assumption ....

Over the years I've come to find that 'smoke and mirrors' only tend to work well when no-one's asking the basic questions - 'how?' & 'why?' ...

HTH
Z

silverwhistle

zeupater wrote: »

Over the years I've come to find that 'smoke and mirrors' only tend to work well when no-one's asking the basic questions - 'how?' & 'why?' ...

In the case of this poster the main question that occurs to me is "why/".

Martyn1981

silverwhistle wrote: »

In the case of this poster the main question that occurs to me is "why/".

The answer to that is beyond me, but there is some good news. At least cepheus' absurd 15pkWh is a vast improvement on his 25p claim only 10 months ago.

cepheus wrote: »

Unfortunately, British households have become confused into believing the overall cost of small scale photovoltaics are becoming competitive in the UK. This is profoundly untrue as can be seen from this recent study of LEVELISED costs. Go to paragrapgh 102 and page 42. small scale solar such as domestic rooftop is around 250 £/MWh verses around half that for larger solar farms. CCGT (Gas) is around 75 £/MWh in comparison. The bottom line is that it isn't sunny in northern Europe. However, Scotland has one of the finest renewable resources in the world, wind.

It took me 16hrs to get to the bottom of that one.

If we are now down to 8.6p or even 10p for super generous rounding, we are certainly making progress fast. 25 - 15 - 10 ...... should be at 7.5 soon, and that'll be game, set and match!

Mart.