My solar PV first year payback calculation

albyota

from Sanyo's component website....guarantee

http://www.sanyo-solar.eu/uploads/media/080604_Guarantee_conditions_HDE1_EN.pdf

BFG_2

Albyota

These are power output guarantees, not installation guarantees.

I suspect that what they mean is that the 'PV' bit of the set-up is 'guaranteed to give 90/80% of max output for 10/20 yrs, NOT the full set up ie the other bots are not guaranteed.

To be valid you'll need to clean etc.

Bit like a car mfg co guaranteeing their gearbox [fairly reliable item anyway] for 25 years ...provided you have the car fully serviced by them every 6 months. They know full well that the car body will wear out in 10 yrs so the gearbox warrant is 'surplus'.

Perhaps a better analogy is a computer compnay giving a guarantee that it's 'processor' will always run at 90% of stated....but the rest of the box will break way ahead of time.

I might be wrong [it wouldn't be the first time, lol]....but i tend to be a bit cynical wrt these 'guarantees' [btw how would you know the PV was down on output??]

Cardew

BFG wrote: »

Albyota

These are power output guarantees, not installation guarantees.

I suspect that what they mean is that the 'PV' bit of the set-up is 'guaranteed to give 90/80% of max output for 10/20 yrs, NOT the full set up ie the other bots are not guaranteed.

To be valid you'll need to clean etc.

That is exactly what it means. That the power output will not fall below 90% and 80%.

In any case how on earth would a domestic customer claim against that guarantee. Try submitting a claim that your system that gave an output of 1,000kWh in 2010 and only 850kWh in 2020.

"Have you cleaned the panels Sir,

Any trees grown near the panels Sir

2010 was an exceptional year for bright clear days Sir,

2020 was an exceptional year for dull cloudy days Sir

Remove the panels from the roof and send them to us for testing in the lab Sir!;)

The system guarantee is for 2 years. It is the cables, connections, mountings, electronics etc.

stevehead

Cardew wrote: »

Steve,
Solar PV is nothing to do with your ASHP system, so to state that Solar will heat your house is totally misleading.(or confusing to those without any technical knowledge)

Your ASHP consumes xxkWh pa and your hope is that a PV array will also generate the same xxkWh pa.

If the 2 totals are the same, then you will be exporting a lot of electricity to the grid, and drawing a lot of electricity from the grid.

So your ASHP is irrelevant to the discussion on the financial viability of solar PV.

Well obviously it's not as simple as just connecting your PV Array to a bar fire, but as an annualised system it does stack up.
The 2 systems are intrinsically linked by my objective, which is to eliminate space heating running costs in a sustainable manner.
If you roll back to my pre ASHP days, when my old GSH was costing me around 700 quid a year, then the heat pump plus PV Array as a system replacement with a net annual heating bill of zero looks quite attractive.

stevehead

[QUOTE=Cardew;25650103
Also everyone seems to ignore the maintenance/cleaning costs for solar panels. Does anyone think a system involving cables, connections and electronics isn't going to give trouble at some point in its life?
[/QUOTE]

Why can't the window cleaners just give them a going over with their fancy long reach equipment they use these days? I have 10 sq m of Water Solar Panels, and I give them a wash down twice a year.
There is no heating system that requires no maintenance at all and never wears out. Your old gas boiler - simple and robust as it is - must have had a few parts replaced and a service cleanout every now and again? Unless the inverters are prone to failure, there's not much else to worry about.
Mmmmm... Perhaps I would worry about that Chinese inverter cooking itself and bursting into flames!

albyota

however much you payed for your car, it only has a 2 - 5 yr conditional warranty. an average mid range family car from new is what.....£9K - £13K?
Whatever you mortgage a house for £xxx,xxx IT only has a TEN year NHBC or similar warranty from new.......almost worthless if you have ever tried to claim....
White goods and TV's are only just starting to offer more than 2 yr warranty's
I think if solar PV is something you want and there is the slight chance of it reducing your energy bills or even generating some income, then what's wrong with that?
some 'property ladder' types bought houses spending large amounts of cash in the hope to increase the price of sale and make them a fat load of money...and a lot of people are actually in negative equity at the moment!, that was a much greater risk that £10k on solar PV.

Cardew

stevehead wrote: »

Why can't the window cleaners just give them a going over with their fancy long reach equipment they use these days? I have 10 sq m of Water Solar Panels, and I give them a wash down twice a year.
There is no heating system that requires no maintenance at all and never wears out. Your old gas boiler - simple and robust as it is - must have had a few parts replaced and a service cleanout every now and again? Unless the inverters are prone to failure, there's not much else to worry about.
Mmmmm... Perhaps I would worry about that Chinese inverter cooking itself and bursting into flames!

Steve,
You have not read the 'exam question' properly.;)

The bills for repair/maintenance of any CH system is not a factor here - doesn't matter if it costs zero or £thousands to maintain.

The 'exam question' is the comparison of projected savings from solar PV over the lifetime of the system, against the capital expenditure/ loss of interest.

I am merely stating that in the lifetime of a solar PV system there will inevitably be a requirement for repairs/maintenance and the cost of those must be offset against savings.

As I said in an earlier post, the financial viability of solar PV has no connection with any CH system(be it ASHP or not). It will save £xx pa and it doesn't matter if you have no CH system at all - solar PV will save £xx pa.

albyota

Other than the panels which have a 2 - 5 yr guarantee or more, the only other bit to be concerned with is the inverter, 'Fronius', and 'Sunny Boy' inverters, I have been looking around the web and there are inverter systems with 5 and 10 year warranty's, the cables and plug and sockets do not perish or fail, the PVC T+E cables in your house will last in excess of 25 years, the isolators will not fail or perish, and the 2 way meter is supplied and is the responsibility of the energy supplier. What else can fail? Yes you may have to factor in a periodic check at a cost of £100 or so every 3/5 years.

The ‘Sunmaster’ is a grid connected solar inverter, used for
the feed back into the utility grid of power generated by
photovoltaic modules.
GUARANTEE SPECIFICATIONS
Mastervolt assures the product guarantee of the
Sunmaster during five years after your purchase, on the
condition that all instructions and warnings given in this
manual are taken into account during installation and
operation.
Among other things, this means that installation is carried
out by a qualified electrician, that installation and
maintenance are executed according to the stated
instructions and correct working sequence and that no
changes or repairs may have been performed on the
Sunmaster other than by Mastervolt.
The warranty is limited to the costs of repair and/or
replacement of the product by Mastervolt only.

stevehead

Cardew wrote: »

Steve,
You have not read the 'exam question' properly.;)

As I said in an earlier post, the financial viability of solar PV has no connection with any CH system(be it ASHP or not). It will save £xx pa and it doesn't matter if you have no CH system at all - solar PV will save £xx pa.

Yep Cardew... granted.
As the PV install is in addition, replacing nothing, then the service costs must be counted and added.

OK then; spending £xx on solar PV will generate KWhxxx and save £xx pa and oohhh, that figure just happens to coincide with my heating requirements.

stevehead

albyota wrote: »

What else can fail?

As long as the panels are insured against storm damage. (extra cost?)
And the seals on the panel casings don't perish
And I've never seen anything electronic last 20 years. Especially if it's on 24/7 and the guts are Chinese.