My solar PV first year payback calculation

Cardew

Mcfi5dhc wrote: »

Hello

The wife doesn't work, so she is in a lot of the time in the day. We have 2 toddlers as well. Mashing machine, dishwasher etc are all on in daylight.

The only electric task we do at night that could reasonably be shifted to the daytime is ironing, but we choose not to cos of the danger of kids running about and tripping on the wires etc (we do team ironing at night though, 2 boards, 2 irons and generally 2 large drinks!)

Back to your point though, if we had a bigger system, we are still going to use roughly the same amount of power in the daytime, so our export amount would rise dramatically. For a 3.700kwp system, we would probably export around 85% (back of a fag packet calcs)

Here is my calc, based on for example "A Shade Greener" set up:
3.7kwp system
12 month generated units = 3200 (North Wales)
I would use 466 units still
I would export 2734
I could estimate 50% of my production and get 3p a unit on this, and get £48
Or, I could use the calcs above and get £82

Thanks.

Your answer is exactly what I had surmised; and for people at work all day it will be even harder to use the electricity during the day.

Somebody posted their output for their A Shade Greener system(which incidentally is 3.3kWp) and the majority of output comes in around midday - even in June as low as 150w in the morning and approaching 3kW at midday.

My point is that I suspect the majority of people with large systems will be exporting far more than the 50% for which they are paid - unless they have an export meter.

That of course also means that they will be using far less than the 50% in the house on which many base their saving calculations.

Cardew

John_Pierpoint wrote: »

How do you heat your water?
( I have sort of searched to see if you answered this question further back:o)

Was it this thread that discussed a gizmo that could turn on something else, such as an immersion heater or a freezer, as the voltage started to rise above the mains, to prevent the export of electricity (worth only 3p a unit) and make sure it is used for something useful on site?

Were you one of the lucky early adopters who qualified for the FiT last April?

Good luck,

John.

McFi's system was installed before the FIT deadline.

The 'Gizmo' was discussed in another thread I believe, but it is very expensive - several hundred pounds I believe.

It is very difficult to think of ways to 'match' consumption in a house to the PV panel output.

Much of the power consumed by washing machines, dishwashers, dryers is by 3kW heaters with which the panels will not cope although putting them on at midday will maximise utilization.

Similarly you could put freezers to 'fast freeze'(if you have that facility) and the compressor will run constantly until switched off. I probably wont come on again during the night.

Mcfi5dhc

John_Pierpoint wrote: »

How do you heat your water?
( I have sort of searched to see if you answered this question further back:o)

Was it this thread that discussed a gizmo that could turn on something else, such as an immersion heater or a freezer, as the voltage started to rise above the mains, to prevent the export of electricity (worth only 3p a unit) and make sure it is used for something useful on site?

Were you one of the lucky early adopters who qualified for the FiT last April?

Good luck,

John.

Thanks for your reply

I heat my water the cheapest, best way possible - gas!

I was the one who raised the possiblility of using EMMA to divert electricty due to be exported to another source (e.g. hot water tank). Another guy worked out it wasn't worthwhile at current prices (which I agree with), though i think the calculation may be different for ASG customers

I was one of the unlucky really early adopters who got a grant (yippeee) but only get 9p a unit (boo)

John_Pierpoint

ASG Customers - sorry I'm not very good at TLA's; can you explain?

Cardew

John_Pierpoint wrote: »

ASG Customers - sorry I'm not very good at TLA's; can you explain?

ASG = A Shade Greener - see this long thread:

https://forums.moneysavingexpert.com/discussion/2072787

A firm in the Yorkshire area that fit a large system for free - but they get the FIT's.

SD-253

I have read somewhere you can have it fitted free and make a bit of money. It says you should go for duel fuel. Firstly I am not on the gas mains and it is never going to be available to me. I presently use LPG and a wood burner. My electricity cost is £22 a month which is a couple of quid above my real costs. I am as you can see relatively frugal I use economy 7 even though I gain little out of it IE I only use about 20% overnight but I believe in it as I think huge amounts of electric are wasted overnight. Obviously wood is a renewable resource and I use LPG for the remainder. Now is it worth me going the solar route I believe you should take it account the cost to the environment of making/building solar power and am always suspicious of anything which is considerably more expensive than the alternative. Can anyone give there opinion on this AND the internet site to go to to look at this........that is the one with the grants and I supposes any other but I particularly like the one where you just get free electric and pay nothing for the panels. I am pretty certain that my GARAGE roof is south facing ALSO my electric meter is in the garage. Anyway hoping to hear from you all with some useful info JB

SD-253

I have read somewhere you can have it fitted free and make a bit of money. It says you should go for duel fuel. Firstly I am not on the gas mains and it is never going to be available to me. I presently use LPG and a wood burner. My electricity cost is £22 a month which is a couple of quid above my real costs. I am as you can see relatively frugal I use economy 7 even though I gain little out of it IE I only use about 20% overnight but I believe in it as I think huge amounts of electric are wasted overnight. Obviously wood is a renewable resource and I use LPG for the remainder. Now is it worth me going the solar route I believe you should take it account the cost to the environment of making/building solar power and am always suspicious of anything which is considerably more expensive than the alternative. Can anyone give there opinion on this AND the internet site to go to to look at this........that is the one with the grants and I supposes any other but I particularly like the one where you just get free electric and pay nothing for the panels. I am pretty certain that my GARAGE roof is south facing ALSO my electric meter is in the garage. Anyway hoping to hear from you all with some useful info JB

John_Pierpoint

Try this thread for the 3 "free" companies involved.
https://forums.moneysavingexpert.com/discussion/2637431

By the way if you click < Edit > on your posting you can delete the duplicate.

cepheus

Why doesn't everyone doing this type their figures into a consistent online calculator, with agreed figures for inflation, interest and price increase?

http://www.reuk.co.uk/REUK-Feed-In-Tariff-Calculator.htm

and state clearly what the solar insolation is in the part of the UK they are using them?




This may also be of some interest

http://re.jrc.ec.europa.eu/pvgis/apps3/pvest.php

cepheus

For a matter of interest what prevents you from producing the electricity you actually use from a Diesel generator and pumping everything from Photovoltaics out and claiming 30 odd pence per kW?

What prevents you from buying a barn in Cornwall and doing this?