My solar PV first year payback calculation

stevehead

OK... from my figures above, I spend £230 a year on heating @10p / KWh.

Say I have a choice: £6,000 to blow on a PV array, or stick it in the bank at 5% interest rate.
Lets pretend that Electricity is going to go up by 10% per KWh per year, and I can always get 5% at the bank.

If I bank it, after 11 years my £6,000 will have become £10,262. But I will have spent £4,262 on electricity in those 11 years so the net balance is still £6,000.

If I buy the PV Array, all I have to do is put the £230 + 10% I would have spent on the electricity into the bank every year. This will become £5,106 after 11 years.

So even without credits, rebates, subsidies etc the payback period is going to be around the 12 year mark.

BFG_2

Stevehead.......so what's your conclusion???

P__G

I say they are worth it and in the long term the price hike is likely to be high for fuel and electricity unless governments are prepared to subsibise it for us (which they probably can't afford to do)

BFG_2

P__G wrote: »

I say they are worth it and in the long term the price hike is likely to be high for fuel and electricity unless governments are prepared to subsibise it for us (which they probably can't afford to do)

Ah, yet another well-evidenced statement.

Just because you 'say they are worth it'...does that somehow bend the laws of mathematics??

You're due a Nobel prize for beng able to change the laws of simple arithmetic.

Try saying 'I will win the lottery tonight', and let me know how you get on.

Honestly, people nowadays can't even do simple maths........[chunters on for several hours]

stevehead

BFG wrote: »

Stevehead.......so what's your conclusion???

My conclusion is that using a PV array to heat your home is a good idea.

BFG_2

stevehead wrote: »

My conclusion is that using a PV array to heat your home is a good idea.

Do you mean a good idea ...
financially???
green???
or 'not being affected by energy strikes???

These are pretty much the only 3 possible reasons [that even come close to being valid]..and even here these have been shown time and time again to be fallacies [search the tyhread/forum for details]

So I'm not sure why you consider it a good idea to invest your money in a system that is neither financially sensible nor particularly green...do pls tell us your logic.

stevehead

Financially
One of the most common arguments I see repeatedly against PV is that you'd be better off just sticking the capital outlay into the bank. What's tactfully overlooked is that you have the money you would have spent on energy available to invest. This adds up to a considerable sum.
That is without Utility Buy-backs, ROC rebates, interest free loans, tax breaks, grants; all these will skew the economics in PV's favour.

Green
I once read that a PV Panel takes more energy to manufacture than it will ever produce in it's lifetime. FALSE
The embedded energy in a PV Panel - the 'old' type - is offset in 8-10 years. This falls considerably as better manufacturing techniques come online.
(Ref: http://www.ecotopia.com/apollo2/pvepbtoz.htm)

The main things that will stop me investing in a PV system are:
Installation industry has a BAD reputation
Grant & Rebate system in a state of flux
Cheaper technology always 'just around the corner'
Priorities - sort out consumption first.

Cardew

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.

The main things that will stop me investing in a PV system are:
Installation industry has a BAD reputation
Grant & Rebate system in a state of flux
Cheaper technology always 'just around the corner'
Priorities - sort out consumption first.

Agree with the above, especially that the solar installation industry has a very bad reputation.
Bearing in mind that you will only get the grants if you use an accredited installer, I fear it will be licence to kill.

I think that systems will cost considerably more than most people anticipate.

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?

Makes you wonder why they only offer a 2 year warranty on the system.

albyota

just found this....
All our products come with a manufacturer’s power output Guarantee for a minimum of 20 years.

In addition to the manufacturer’s backed guarantee, which covers the equipment, you will receive a guarantee for the installation from REIGA (Renewable Energy Installation Guarantee Agency). This will be applied for on your behalf and sent to you direct from REIGA. It can take up to 8 weeks from installation to be delivered.
REIGA is an independent non-profit guarantee agency. Its only function is to stand as guarantor for the promises set out in the guarantee. It has all the resources to meet the promises made in the guarantee.
For further information see www.reiga.org.uk

n 2 year product guarantee

n 10 year performance guarantee for a 90% power output

n min. 20 year performance guarantee for a 80% power output

albyota

and from another site...

25 year Power Warranty: Power output for the KC series of mobiles is guaranteed to be not less than 90% of minimum rated power for a period of 12 years from the date of purchase AND not less than 80% of minimum rated power for a period of 25 years from the date of purchase.