Solar Panels?

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Discussion

gazapc

1,322 posts

162 months

Sunday 27th March 2022
quotequote all
essayer said:
So if those 260 panels were mounted at the perfect angle at peak summer they would each supply just over 1A at 240v? Or is it not that simple?
The operating voltage of the individual panels is more like 35V and perhaps 8 amps.

You daisy chain them together in series to make a string of a few hundred volts.

The power is put through an inverter to convert to AC power and a usable voltage.

Edit: in the UK its actually possible to get them to produce more than 260 Watts, particularly if it is cold and sunny.


For playing around with these repurposed panels are OK but there is a reason why the company will be getting rid of them after a storm. So don't be surprised if power output is lower or declines quicker in the long run.

Edited by gazapc on Sunday 27th March 13:26

Gareth79

7,730 posts

248 months

Sunday 27th March 2022
quotequote all
gazapc said:
For playing around with these repurposed panels are OK but there is a reason why the company will be getting rid of them after a storm. So don't be surprised if power output is lower or declines quicker in the long run.
Looking at the photos, if any bank of panels had any damage it'd need completely stripping down, and by the time you've taken them down it's probably better to simply rebuild using more modern ones rather than having a mix:

https://www.gazettelive.co.uk/news/teesside-news/f...

edit: I was messing around with ideas for mounting them to my patio polycarbonate roof today, it's a regular triple-wall thing. I want to keep it completely free of the roof itself (otherwise it will get messy, so I'm thinking 2x 34mm steel tubes horizontally, and then 1x tube running down the centre of the roof from the wall (bolted) and then attached to the front of a rafter, to support the middle. The other option is to make an S-shaped bracket to slip under the panels and bolt to a rafter, which I think would be a better option even though it risks making the roof a bit leaky there.

Edited by Gareth79 on Sunday 27th March 20:59

g40steve

931 posts

164 months

Saturday 2nd April 2022
quotequote all
Had the site survey done & Vat now 0 so quote is 5% cheaper.
Just need a date so they can get it fitted but demand has exploded frown

Enut

764 posts

75 months

Saturday 2nd April 2022
quotequote all
Bit of a thread hijack but I had a quote agreed via a local scheme with Solar Together back in October 2010, but it still hasn't been fitted!

I phoned them again last week and was told they still didn't have a fitting date for me, 'because they're really busy', well I doubt if they are going to get less busy now with the zero VAT deal!

Anyway does anyone have any good Solar company recommendations in the South East (East Sussex) as it looks like I might have to look elsewhere.

Chris Type R

8,070 posts

251 months

Saturday 2nd April 2022
quotequote all
Enut said:
Bit of a thread hijack but I had a quote agreed via a local scheme with Solar Together back in October 2010, but it still hasn't been fitted!
You've been extremely patient....

NMNeil

5,860 posts

52 months

Saturday 2nd April 2022
quotequote all
gazapc said:
The operating voltage of the individual panels is more like 35V and perhaps 8 amps.

You daisy chain them together in series to make a string of a few hundred volts.

The power is put through an inverter to convert to AC power and a usable voltage.

Edit: in the UK its actually possible to get them to produce more than 260 Watts, particularly if it is cold and sunny.


For playing around with these repurposed panels are OK but there is a reason why the company will be getting rid of them after a storm. So don't be surprised if power output is lower or declines quicker in the long run.

Edited by gazapc on Sunday 27th March 13:26
Most, if not all solar panels, have a spec sheet on the back, like this.


GT89

383 posts

115 months

Sunday 3rd April 2022
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Using this as a sounding board, in my loft I have a large megaflow hot water tank with back up Immersion heaters incase of boiler failure.

I also have a hot water tanker in my garage that serves hot water to the annex above it, this setup is purely electric.

The house does have a South facing roof but I have multiple south west facing ones too.
In my dad's loft is a divirter he had installed for a short period of time before he has a new combi boiler fitted, it currently resides in the loft disconnected.

Would there be potential worth to me getting said divirter and a small system on the roof to purely heat the hot water or would I just be wasting time and effort ?

AW10

4,444 posts

251 months

Sunday 3rd April 2022
quotequote all
Payback time is probably 10 years or so - best payback would be to further insulate the tanks to prevent heat loss regardless of where the energy to heat them is coming from.

Those diverters are all good and fine but of little practical value unless you can time your hot water consumption to after they’ve heated the tank. So not much use for morning showers/baths unless the tank is very well insulated and has hot water from the day before; see my point above.

Lily the Pink

5,783 posts

172 months

Sunday 3rd April 2022
quotequote all
A word of warning - don't be misled by kWh (energy) figures, when it is actually kW (power) that is more important. If you don't use the power when it's being generated then you need to either export, store or waste it. This graph shows how much I imported, averaged across all days in March. The small peak around 8-8:30 is probably showers and kettle going on before much solar is generated, while the large peak around 19:00 will be cooking the evening meal. The peaks from 11:30-13:00 reflect just one overcast day when I needed to charge my car for the evening. Otherwise I used virtually nothing from mid morning through the afternoon, and would have had plenty to store or sell if I had a battery or export MPAN, both of which are being considered. If I had a 10kWh battery, I think I probably would have lasted the whole month without taking anything from the grid.

mrmistoffelees

287 posts

71 months

Sunday 3rd April 2022
quotequote all
Lily the Pink said:
A word of warning - don't be misled by kWh (energy) figures, when it is actually kW (power) that is more important. If you don't use the power when it's being generated then you need to either export, store or waste it. This graph shows how much I imported, averaged across all days in March. The small peak around 8-8:30 is probably showers and kettle going on before much solar is generated, while the large peak around 19:00 will be cooking the evening meal. The peaks from 11:30-13:00 reflect just one overcast day when I needed to charge my car for the evening. Otherwise I used virtually nothing from mid morning through the afternoon, and would have had plenty to store or sell if I had a battery or export MPAN, both of which are being considered. If I had a 10kWh battery, I think I probably would have lasted the whole month without taking anything from the grid.
What's your array size and rough orientation?

Lily the Pink

5,783 posts

172 months

Sunday 3rd April 2022
quotequote all
mrmistoffelees said:
What's your array size and rough orientation?
12.775kWp (probably about 10kWp after PVGIS), azimuth about 165, slope about 15 degrees.

Jambo85

3,330 posts

90 months

Sunday 3rd April 2022
quotequote all
AW10 said:
Payback time is probably 10 years or so - best payback would be to further insulate the tanks to prevent heat loss regardless of where the energy to heat them is coming from.

Those diverters are all good and fine but of little practical value unless you can time your hot water consumption to after they’ve heated the tank. So not much use for morning showers/baths unless the tank is very well insulated and has hot water from the day before; see my point above.
You’re the second person to have mentioned this in the thread. I have a diverter and I don’t have this issue, am I an outlier?

My tank stat (for the boiler) is set about 60C I think, whereas my immersion stat is set to maximum (whatever that is). Year round, the boiler is set to heat hot water from 7-8pm only.

We always have hot water for morning showers and all other uses including hot fed dishwasher, and the boiler rarely has to do much for hot water between March and September.

The tank is only 3 yrs old so I guess has excellent insulation but I don’t think that’s unusual?

Chris Type R

8,070 posts

251 months

Sunday 3rd April 2022
quotequote all
I've only recently connected up a diverter, but we're the same - we have the boiler heat the water in the late afternoon & it's fine for a bath in the evening and then shower(s) in the morning. It's decently insulated but probably fairly old - certainly over 7 years. The cylinder is in an airing closet, which has loft insulation above.

I think our washing machine and dishwasher both heat the water - we try and time this for during the day when there's a chance of solar being used.

cayman-black

12,706 posts

218 months

Sunday 3rd April 2022
quotequote all
Chris Type R said:
Enut said:
Bit of a thread hijack but I had a quote agreed via a local scheme with Solar Together back in October 2010, but it still hasn't been fitted!
You've been extremely patient....
Are you sure they are still in business?

Enut

764 posts

75 months

Sunday 3rd April 2022
quotequote all
cayman-black said:
Chris Type R said:
Enut said:
Bit of a thread hijack but I had a quote agreed via a local scheme with Solar Together back in October 2010, but it still hasn't been fitted!
You've been extremely patient....
Are you sure they are still in business?
Well they did answer the phone and fob me off with a 'can't give you a date yet I'm afraid' Hence the request for other suppliers/fitters in the Sussex area as I'm not getting more than fed up waiting.

AW10

4,444 posts

251 months

Monday 4th April 2022
quotequote all
Jambo85 said:
You’re the second person to have mentioned this in the thread. I have a diverter and I don’t have this issue, am I an outlier?

My tank stat (for the boiler) is set about 60C I think, whereas my immersion stat is set to maximum (whatever that is). Year round, the boiler is set to heat hot water from 7-8pm only.

We always have hot water for morning showers and all other uses including hot fed dishwasher, and the boiler rarely has to do much for hot water between March and September.

The tank is only 3 yrs old so I guess has excellent insulation but I don’t think that’s unusual?
If you’ve had better experiences than me then all good. In my case (house now sold) I suspect the immersion element wasn’t a particularly large one that was at the top of the cylinder so there was probably stratification in the water. And I couldn’t raise the immersion thermostat to the max as that could have meant water hotter than the shower pump was rated for (max of 60C or the warranty was void). I found the hot water supply sufficient for just one shower mid-morning and I could feel it cooling near the end.

Jambo85

3,330 posts

90 months

Monday 4th April 2022
quotequote all
AW10 said:
If you’ve had better experiences than me then all good. In my case (house now sold) I suspect the immersion element wasn’t a particularly large one that was at the top of the cylinder so there was probably stratification in the water. And I couldn’t raise the immersion thermostat to the max as that could have meant water hotter than the shower pump was rated for (max of 60C or the warranty was void). I found the hot water supply sufficient for just one shower mid-morning and I could feel it cooling near the end.
Thanks - my element is near the bottom of the tank so indeed that will make quite a difference, as will tank temperature as you say. A blending valve could have been a solution in your case but yet more cost!

Presumably your tank would only accept a low kWh of input each day too?

GasEngineer

987 posts

64 months

Monday 4th April 2022
quotequote all
Enut said:
cayman-black said:
Chris Type R said:
Enut said:
Bit of a thread hijack but I had a quote agreed via a local scheme with Solar Together back in October 2010, but it still hasn't been fitted!
You've been extremely patient....
Are you sure they are still in business?
Well they did answer the phone and fob me off with a 'can't give you a date yet I'm afraid' Hence the request for other suppliers/fitters in the Sussex area as I'm not getting more than fed up waiting.
The cost of materials will have changed significantly ovrt 12 years as well as the effects of inflation etc.
Its also very unlikely that the equipment in your quote will still be available.


Condi

17,352 posts

173 months

Monday 4th April 2022
quotequote all
AW10 said:
If you’ve had better experiences than me then all good. In my case (house now sold) I suspect the immersion element wasn’t a particularly large one that was at the top of the cylinder so there was probably stratification in the water. And I couldn’t raise the immersion thermostat to the max as that could have meant water hotter than the shower pump was rated for (max of 60C or the warranty was void). I found the hot water supply sufficient for just one shower mid-morning and I could feel it cooling near the end.
I know 2 or 3 people with either solar hot water or PV with diverter and non need to pay much if anything for hot water through most of summer and autumn.

ARHarh

3,836 posts

109 months

Monday 4th April 2022
quotequote all
Condi said:
AW10 said:
If you’ve had better experiences than me then all good. In my case (house now sold) I suspect the immersion element wasn’t a particularly large one that was at the top of the cylinder so there was probably stratification in the water. And I couldn’t raise the immersion thermostat to the max as that could have meant water hotter than the shower pump was rated for (max of 60C or the warranty was void). I found the hot water supply sufficient for just one shower mid-morning and I could feel it cooling near the end.
I know 2 or 3 people with either solar hot water or PV with diverter and non need to pay much if anything for hot water through most of summer and autumn.
my house has had solar thermal since 1999 (previous owner put it in), and i pay pretty much nothing for hot water from may till October.