Question re output of Home Solar

Emmit

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Can I ask a question.

We are about to have solar bolted onto the roof of Chez Emmit.

I understand that there will be 4800 Watts on the roof which faces due South.

I know that starting at dawn the panels will produce Bu&&er all but through the day, given brightness, the amps will flow.

Can anyone give me a 'ball park' figure on how much can be expected to flow off the roof.

We are anticipating having a simple 'No battery' system.
Thank you in advance.
 
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We have averaged 3300kW per year over the last 10 years - mostly in the summer.

You will find it difficult to use all that you generate. We try and use washing machine, tumble dryer, dishwasher etc during sunny times, but its not always easy.
 
Can anyone give me a 'ball park' figure on how much can be expected to flow off the roof.

We are anticipating having a simple 'No battery' system.
You'll see all that expensive energy flowing into the grid, presumably you're getting nothing for it. Then you have to pay in mornings and evenings when that's when you actually want to use it. You'll soon be thinking of hooking on a battery to provide for all your background loads at least. :wondering: :giggle:

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Ballpark figure, 3kW or more in full sunlight, around 1kW on a normal cloudy day, on a dull winter day maybe enough to charge your phone.

Yes, that is similar to our experience with mono crystals. Poly are slightly less efficient.

We put a battery in last October. The panels have been in for several years and give an income of over £2000 a year.
 
Output will also depend on the angle of the roof. About 40 degrees is the optimum. My south facing 4Kw array has a fairly shallow pitch and has an annual output of around 4000-4300 pa.
 
Its always good to hear from those with experience of how much yield can realistically achieved from a home solar install, thanks to all that give us some answers.
I like many, did look at this solar proposition in the age of massive energy cost rises, expecting to be fairly paid for any surplus energy that was pumped back into the grid to reduce my monthly bill for Electricity.
I was shocked to see the miserly amount some energy providers were prepared to offer me back in return on their FIT (feed in tariff) I wont quote figures just now, as it would seem that unless you had set the deal up years ago, you could only expect to get a very much reduced FIT today. Some energy providers now state that they are not offering an new FIT contracts to customers with new solar installs.
Why is this current totally unfair FIT situation allowed to continue?
Yes, we would need our own storage batteries, use them to their fullest extent, or otherwise it doesn't make it an attractive proposition with the huge upfront install costs, and expected payback term. (I know with higher costs the payback term will be reduced)
Better, fairer FIT contracts would entice more people to invest, and be self sufficient.
I need not mention the Carbon Footprint, CO2 emission reduction, as that's what we as a nation/world are trying to address, but we need to be treated more fairly, as the current offering is not attractive enough, so many will either put off having it installed, or delay until there is a better deal on the table.
LES
 
We are south facing and have 4kWh panels which currently start to produce enough to cover base load @ 08:00. Over the past three months the lowest daily yield was 5 kWh and the most was 22kWh. We tend to use 6-10 kWh per day. I was going to add another 1.5kWh, but its pointless as we tend to export half of what we produce. We have 16kWh batteries which keep us going at night and we can also top up at 7.5p overnight if needed. If you install a battery as part of the install it will be VAT free, it wont be if you do it later.
We are paid 24p per kW generated on the FIT scheme.
 
We’re just in process of getting some. 4kw of panels estimated to give 3600kw per annum.

Neighbour had just had them fitted so he’s watchn app like a hawk.

We’ve gone for having panels hooked up to a domestic hot water tank so any excess power not being used heats water first then returns excess to grid. Will cut down on oil useage as well.

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I checked it out and unless I am prepared to stay in my home for a considerable number of years it did not seem worth it to me. I used the calculator on the energy savigns trust site https://www.pvfitcalculator.energysavingtrust.org.uk/

If I added batteries it might be better but then the cost of them just lenghtens the break even period. Seems to me there are too many uncertainties at the mo.

Also if you are using your motorhome a lot you are home for less time and the break even point gets even further away.
 
From our victron web, we have 20 panels about 5KW, we are 59 degrees north (about Orkney Islands)


Screenshot 2022-09-07 at 18.59.23.png
 

These calculations assume a 25 year life of the solar panel. It is highly unlikely that I shall be in this house for the next 25 years so not worth it for me and I am buggered if I am going to let someone else benfit from my investment.

Your results​

For more information, please read the calculator assumptions.


Potential annual benefit£465

Potential CO2 saving718 kg / year
Potential fuel bill saving £394 / year
Potential payments from SEG
(at 4.1 p/kWh) £70 year

Potential lifetime benefit £11,259

Potential lifetime CO2 saving 16,872 kg
Potential lifetime fuel bill saving £9,664
Potential lifetime payments from SEG
(at 4.1 p/kWh) £1,595

Estimated installation costs £5,942

Estimated lifetime maintenance costs £1,450

Potential lifetime net benefit £3,867
 
Why is this current totally unfair FIT situation allowed to continue?
Wait till they get you on the spanish system whereby you supply all the infrastructure & pay for it & they just charge you less per hour for what you use than the peasants are paying; at the moment.? Battery is far better.

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Our West facing array gives about 3Mw a year give or take a bit. Fortunately we got in just before FIT was made defunct so with judicious use of appliances during export periods it will take about 8-9 years to pay for itself depending on how much our normal bill goes up when our fix runs out..
Why they don't re-introduce FIT defeats me but even more silly, why aren't they insisting on PVs on every new-build? The cost is insignificant to a developer.
 
Can I ask a question.

We are about to have solar bolted onto the roof of Chez Emmit.

I understand that there will be 4800 Watts on the roof which faces due South.

I know that starting at dawn the panels will produce Bu&&er all but through the day, given brightness, the amps will flow.

Can anyone give me a 'ball park' figure on how much can be expected to flow off the roof.

We are anticipating having a simple 'No battery' system.
Thank you in advance.
Our roof faces SSW at an angle of 43 degrees

We had a 4.38kW system fitted on 06/12/21 limited to max 3.68kW output (which it doesn't maintain for very long when it reaches it). Since then we have produced 4.24MWh. I think this year has been sunnier than average since our predicted yearly production was 3.574MWh.

You'll see all that expensive energy flowing into the grid, presumably you're getting nothing for it. Then you have to pay in mornings and evenings when that's when you actually want to use it. You'll soon be thinking of hooking on a battery to provide for all your background loads at least. :wondering: :giggle:
You are spot on with this! Less than a year on and we have just booked to have a battery fitted. It is galling to have to buy back what I've exported at 7 times the price I get paid for it.
 
why aren't they insisting on PVs on every new-build? The cost is insignificant to a developer.
they do ; but only for any social housing that the developer has to build. Those paying full price get sweet fa.
 

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