Discussion
AW10 said:
Time for my periodic post… it’s not ROI; it’s the payback period.
It would be great if some of the people that installed systems a year or more ago would post their data collected over a year of real world use so that folks considering installing a system have some real world figures to evaluate. Calculators and predictors and sales bumph are all good and fine but bring data!
What do you want to know? We had solar installed in May 2022 and the Tesla Powerwall 2 was installed on 17/03/2023. I have just over 12 months of real data on both.It would be great if some of the people that installed systems a year or more ago would post their data collected over a year of real world use so that folks considering installing a system have some real world figures to evaluate. Calculators and predictors and sales bumph are all good and fine but bring data!
AW10 said:
Time for my periodic post… it’s not ROI; it’s the payback period.
It would be great if some of the people that installed systems a year or more ago would post their data collected over a year of real world use so that folks considering installing a system have some real world figures to evaluate. Calculators and predictors and sales bumph are all good and fine but bring data!
Some very quick maths show me, I spent £460.35 this year on electric. The last full year, without solar, was £1300ish. This though, was before we bought an electric car. So the current years figures include charging the car, which wouldn't have been on the £1300 figure. It would be great if some of the people that installed systems a year or more ago would post their data collected over a year of real world use so that folks considering installing a system have some real world figures to evaluate. Calculators and predictors and sales bumph are all good and fine but bring data!
What I would like to know , does anyone have a system that covers all there yearly electric use? I have been quoted a system that they say will ?.
I see here that the consensus is its over priced so will look at getting other quotes but I want to get a system that covers my yearly spend?
My post below page 110
I have just had a quote from Project Solar 12 panels ground mounted 5.46kW output with a 5.8kW Battery £14500. I have no idea if this is good or not as it's the first quote I have had. Oh and I know nothing about SPs. . annual consumption is around 5013kWhs
I see here that the consensus is its over priced so will look at getting other quotes but I want to get a system that covers my yearly spend?
My post below page 110
I have just had a quote from Project Solar 12 panels ground mounted 5.46kW output with a 5.8kW Battery £14500. I have no idea if this is good or not as it's the first quote I have had. Oh and I know nothing about SPs. . annual consumption is around 5013kWhs
We moved in to a house two years back that has 12 Panels on the roof that were installed 20 years back by one of the companies that leased your roof space and installed for free.
So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
Aprisa said:
We moved in to a house two years back that has 12 Panels on the roof that were installed 20 years back by one of the companies that leased your roof space and installed for free.
So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
Are you able to see how efficient the panels are now, compared to a few years ago?So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
Presumably panels have two failure modes - loss of efficiency or just stopping completely ?
KTF said:
I agree that the financial side is hard to history with such low usage. An EV is in the pipeline through work which should then make it more useful to have as that will bump the consumption figures up.
As an EV user, I would suggest that using one would make things worse rather than better.I only need to charge mine when it is cheap - or even like today when it is free - so you are likely to be filling it with either expensive flux electricity or solar electricity which could have been exported to the grid for a higher price than you would otherwise have paid if you hadn't had solar.
KTF said:
Yes. That is the dilemma.
On tracker you can, for example, import at 18 and export at 15.
So if you export lots then every import costs you 3p as it balances out.
At least that’s what my man maths tells me
Just out of interest have you worked out your export £ return based on what the DNO have said you can export or what the max is for the system?On tracker you can, for example, import at 18 and export at 15.
So if you export lots then every import costs you 3p as it balances out.
At least that’s what my man maths tells me
MaxFromage said:
I'm a broken record (and we've recently had the discussion), but the inverter is too small, even for East/West. The professionals championing smaller inverters (science is questionable IMO) would say so too at less than 60%.
In this case, I'd say you're right as the the DC power limit of that inverter is only 7.5KW, and my understanding is that going over the max oversize could void the warranty.Fitting a more powerful inverter would prevent some loss of generation from clipping, but often it's all about cost.
We went with a 3.68KW inverter, as a 5KW one...
...would have required DNO approval prior to install (extra cost, and delay)
...could easily have only been granted the same 3.68KW export limit
...would have required a chunkier armoured cable between house and garage
...which would have involved digging up the driveway, paving slabs, etc..
cayman-black said:
What I would like to know , does anyone have a system that covers all there yearly electric use? I have been quoted a system that they say will ?.
It will be the size of a football field, or have a very large battery, or you don't use much electricity.You need to know ...
Daily usage, both average and peak.
Latitude, shading, orientation and roof angle will tell you the average expected solar generation per day of the year assuming unbroken sunshine. Now, estimate cloud cover per day. This will tell you a more realistic generation figure. Does the worst case scenario cover a day's usage? If not, how big a battery will you need to supply you for this day AND yesterday if it were as bad, and the day before.
Worst case scenario is 21 December with unbroken cloud all day.
This was my solar generation for the period around Christmas...
| Date | kWh |
|---|---|
| 12/12/2023 | 1.00 |
| 13/12/2023 | 0.70 |
| 14/12/2023 | 2.60 |
| 15/12/2023 | 0.90 |
| 16/12/2023 | 6.80 |
| 17/12/2023 | 0.90 |
| 18/12/2023 | 0.70 |
| 19/12/2023 | 0.70 |
| 20/12/2023 | 1.30 |
| 21/12/2023 | 2.50 |
| 22/12/2023 | 0.50 |
10x490W panels, 165°orientation, 35°roof, 52.89°latitude.
My average during the period was 9.04kWh with a peak of 10.70kWh. As you can see, there is no way that my solar would cover my daily use. I would need more than 50 panels to cover my average daily for the period.
t.KTF said:
A DNO request is free. Some installers may charge for their time but there is no fee to submit the form.
Ah, thanks. I'd thought G98 was free but G99 was chargeable.KTF said:
If you max out your inverter it just clips rather than voids the warranty.
On the AC side, sure. But on the DC side?Otherwise, how does a 'maximum oversize' limit affect anything? Why would manufacturers spec this?
A g98 is auto approved up to 3.68 which is why many installers/inverters spec this.
Above this you need a g99 where you submit the design to the DNO and they can say how much you are allowed to export so the infrastructure isn’t over stressed.
The one for my area, SSEN aims to turn these round within 10 working days.
This blog explains about the oversizing aspect. Other sources are available.
https://www.solaredge.com/uk/solaredge-blog/oversi...
Above this you need a g99 where you submit the design to the DNO and they can say how much you are allowed to export so the infrastructure isn’t over stressed.
The one for my area, SSEN aims to turn these round within 10 working days.
This blog explains about the oversizing aspect. Other sources are available.
https://www.solaredge.com/uk/solaredge-blog/oversi...
pingu393 said:
What do you want to know? We had solar installed in May 2022 and the Tesla Powerwall 2 was installed on 17/03/2023. I have just over 12 months of real data on both.
In KWh - monthly total consumption plus split by panels/battery/import. Monthly export.Monthly financials. Details on the tariff.
Array size, orientation and location. Battery and inverter size. Any major out-of-the-ordinary electricity consumers such as EV, AC, hot tub, swimming pool, heat pump, etc.
Aprisa said:
We moved in to a house two years back that has 12 Panels on the roof that were installed 20 years back by one of the companies that leased your roof space and installed for free.
So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
Hope you checked the income before saying no. Paid 15k for a 2nd hand setup 10 years ago, averaging over 5k a year and contract runs until 2035So, the only benefit we get at the moment is the use of the power generated during the day by whatever we switch on assuming it uses less than the panels are producing.
When we moved in, the Company wanted around 12K for us to buy the panels which was obviously way too much, and more than a new setup with battery, however it is on a better feed in tariff for the remaing years and so we could expect some cash back.
Question for you experts is:- should we think of buying them as the terms comes to and end as the sliding scale will make them cost about 5K next year coming down by a couple of K to when they have 2 years to go. Will the panels be pretty much dead at the end of 25 Years and will be able to use any of the infrastructure or controls afterwards if we were to look at fitting new panels?
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
Aprisa said:
Bit vague I'm afraid but we don't have access to any figures for what is being produced as we don't own the setup. Thanks
So how does the company know what is being produced?There should (legally) be a generation meter. And usually you have to provide the reading to the owner of the system. Then usually on a FiT it's assumed that 50% is exported.
The issue is also that replacing the system will probably need to be from scratch to qualify for a SEG deal following on. Panels sizes have changed and sparkys hate putting their name to someone else's wiring.
I expect it's going to be a growing headache for the first gen systems.
AW10 said:
pingu393 said:
What do you want to know? We had solar installed in May 2022 and the Tesla Powerwall 2 was installed on 17/03/2023. I have just over 12 months of real data on both.
In KWh - monthly total consumption plus split by panels/battery/import. Monthly export.Monthly financials. Details on the tariff.
Array size, orientation and location. Battery and inverter size. Any major out-of-the-ordinary electricity consumers such as EV, AC, hot tub, swimming pool, heat pump, etc.
No out-of-the-ordinary electricity consumables. Gas C/H. Gas cooker. No dishwasher.
Octopus Tracker (average between 11/02/2023 and 15/03/2024 = 17.8ppkWh inc VAT)
Octopus Export (15ppkWh inc VAT)
| Month | Consumption | Panels | Battery | Import | Export |
|---|---|---|---|---|---|
| Jan 2024 | 290.7 | 124.6 | 78.6 | 182.2 | 0.0 |
| Feb 2024 | 278.7 | 137.8 | 62.7 | 155.3 | 0.0 |
| Mar 23 / 24 (**) | 293.8 | 202.0 | 125.7 | 94.4 | 1.9 |
| Apr 2023 | 262.8 | 404.4 | 149.0 | 9.9 | 116.8 |
| May 2023 | 286.5 | 496.0 | 154.9 | 0.8 | 194.3 |
| Jun 2023 | 261.2 | 539.7 | 130.3 | 3.2 | 250.2 |
| Jul 2023 | 285.6 | 425.2 | 150.8 | 19.1 (x) | 139.3 |
| Aug 2023 | 297.4 | 432.4 | 167.2 | 1.2 | 108.0 |
| Sep 2023 | 277.3 | 341.0 | 142.0 | 57.6 (x) | 98.1 |
| Oct 2023 | 286.9 | 204.4 | 107.2 | 131.4 | 36.6 |
| Nov 2023 | 260.1 | 150.7 | 91.3 | 127.6 | 0.2 |
| Dec 2023 | 287.5 | 62.9 | 39.9 | 239.9 | 3.8 |
(x) There were two days where the export rate was higher than the import rate, so I imported, just to export
(*) I thought my panels were 490W, but they are actually 370W
(**) 01/03/2024-16/03/22024 and 17/03/2023-31/03/2023
I think that's it.
cayman-black said:
What I would like to know , does anyone have a system that covers all there yearly electric use? I have been quoted a system that they say will ?.
I see here that the consensus is its over priced so will look at getting other quotes but I want to get a system that covers my yearly spend?
My post below page 110
I have just had a quote from Project Solar 12 panels ground mounted 5.46kW output with a 5.8kW Battery £14500. I have no idea if this is good or not as it's the first quote I have had. Oh and I know nothing about SPs. . annual consumption is around 5013kWhs
Do a search online for project solar. They do not have the best reputation.I see here that the consensus is its over priced so will look at getting other quotes but I want to get a system that covers my yearly spend?
My post below page 110
I have just had a quote from Project Solar 12 panels ground mounted 5.46kW output with a 5.8kW Battery £14500. I have no idea if this is good or not as it's the first quote I have had. Oh and I know nothing about SPs. . annual consumption is around 5013kWhs
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