Solar Panels?

[Flooble]

Do the other roofs shade where you will be putting the panels? Shading is really critical, especially if they aren't using microinverters.

I had a quote for our house, similarly T-shaped, and the honest surveyor said that there was no point putting panels on a large chunk of the roof as one part or the other was shaded by the rest of it.

[C70R]

Flooble said:

Do the other roofs shade where you will be putting the panels? Shading is really critical, especially if they aren't using microinverters.

I had a quote for our house, similarly T-shaped, and the honest surveyor said that there was no point putting panels on a large chunk of the roof as one part or the other was shaded by the rest of it.

No, the roof faces of the T 'leg' extension are to the South of the main part of the house. They are unobstructed.

I guess my concern was that they would only be getting half a day of direct sunlight each. And that 6 or 7 panels producing 2kwh from half a day of sunlight felt like a lot.

ETA - the kWh figures are per year, if that wasn't obvious

Edited by C70R on Monday 27th March 13:15

[C70R]

Full quote is in. 13 panels, 2 batteries and associated gubbins comes to £12k. Bang in line with what I'd expected.

[Flooble]

C70R said:

Flooble said:

Do the other roofs shade where you will be putting the panels? Shading is really critical, especially if they aren't using microinverters.

I had a quote for our house, similarly T-shaped, and the honest surveyor said that there was no point putting panels on a large chunk of the roof as one part or the other was shaded by the rest of it.

No, the roofs of the T 'leg' extension are to the South of the main part of the house. They are unobstructed.

I guess my concern was that they would only be getting half a day of direct sunlight each. And that 6 or 7 panels producing 2kwh from half a day of sunlight felt like a lot.

ETA - the kWh figures are per year, if that wasn't obvious

If they were 500w panels, then 6 of them would have a peak of 3000W, so 3 hours' sunlight would be 9kWh. Even 400w panels would give you 7200kWh. Take off the efficiency losses, cloud losses etc. and 2kWh still seems reasonable.

[Road2Ruin]

C70R said:

Full quote is in. 13 panels, 2 batteries and associated gubbins comes to £12k. Bang in line with what I'd expected.

Difficult to say without seeing the details. The batteries could be tiny, the panels could be low kw.

To give you a comparative. We have 11 x 400kw panels (these are built into the roof, rather than mounted on top,which generally is more expensive), hybrid inverter, and 9.5kwh battery. This was £12.5k.

[C70R]

Flooble said:

C70R said:

Flooble said:

Do the other roofs shade where you will be putting the panels? Shading is really critical, especially if they aren't using microinverters.

I had a quote for our house, similarly T-shaped, and the honest surveyor said that there was no point putting panels on a large chunk of the roof as one part or the other was shaded by the rest of it.

No, the roofs of the T 'leg' extension are to the South of the main part of the house. They are unobstructed.

I guess my concern was that they would only be getting half a day of direct sunlight each. And that 6 or 7 panels producing 2kwh from half a day of sunlight felt like a lot.

ETA - the kWh figures are per year, if that wasn't obvious

If they were 500w panels, then 6 of them would have a peak of 3000W, so 3 hours' sunlight would be 9kWh. Even 400w panels would give you 7200kWh. Take off the efficiency losses, cloud losses etc. and 2kWh still seems reasonable.

That sounds sensible. Thanks for the sense-check.

[C70R]

Road2Ruin said:

C70R said:

Full quote is in. 13 panels, 2 batteries and associated gubbins comes to £12k. Bang in line with what I'd expected.

Difficult to say without seeing the details. The batteries could be tiny, the panels could be low kw.

To give you a comparative. We have 11 x 400kw panels (these are built into the roof, rather than mounted on top,which generally is more expensive), hybrid inverter, and 9.5kwh battery. This was £12.5k.

13x 415Kw panels, 2x 5.8kWh batteries, hybrid inverter.

[Road2Ruin]

C70R said:

Road2Ruin said:

C70R said:

Full quote is in. 13 panels, 2 batteries and associated gubbins comes to £12k. Bang in line with what I'd expected.

Difficult to say without seeing the details. The batteries could be tiny, the panels could be low kw.

To give you a comparative. We have 11 x 400kw panels (these are built into the roof, rather than mounted on top,which generally is more expensive), hybrid inverter, and 9.5kwh battery. This was £12.5k.

13x 415Kw panels, 2x 5.8kWh batteries, hybrid inverter.

I would say, from my experience, that seems quite competitive.

[C70R]

Road2Ruin said:

C70R said:

Road2Ruin said:

C70R said:

Full quote is in. 13 panels, 2 batteries and associated gubbins comes to £12k. Bang in line with what I'd expected.

Difficult to say without seeing the details. The batteries could be tiny, the panels could be low kw.

To give you a comparative. We have 11 x 400kw panels (these are built into the roof, rather than mounted on top,which generally is more expensive), hybrid inverter, and 9.5kwh battery. This was £12.5k.

13x 415Kw panels, 2x 5.8kWh batteries, hybrid inverter.

I would say, from my experience, that seems quite competitive.

Thank you

[C70R]

One other question. I have oil-fired hot water, but also have an immersion heater in the bottom of the tank. I was planning to switch our water heating over to electricity rather than oil as part of this. The heater has a simple on/off isolator switch at the moment. I assume replacing it with something like this would suffice? https://www.directtradesupplies.co.uk/product.php/...

[Arnold Cunningham]

2 weeks in. 21x panels, 2x 9.5kWH batteries, 1x 5kW hybrid inverter. Combined with off peak charging, our average cost, inc standing charge, has reduced from about a tenner a day to a quid. We no longer consume any peak time power, we charge the batteries up, if they’re too low, off peak and the house runs entirely off solar and battery now. (Obvs I know middle of winter will be less solar and more battery, but I reckon we can still operate using mostly off peak power)

Happy with that.

Edited by Arnold Cunningham on Monday 27th March 20:51

[MaxFromage]

C70R said:

The house is effectively T-shaped, with the T lying in perfect North-South orientation. The 'leg' of the T is a more modern two-storey extension to the rear/South (East/West pitched roof), so we decided they would put together a quote based on installing here (terracotta tiles). In total they sized up space for 13 panels, and estimated that with minimal tree coverage I should get decent returns. Through looking at our usage (we're on Octopus Go), they estimated two batteries would be sufficient to meet our needs.

I'm waiting on the full quote to land today, but having seen the survey report already I wanted to sense-check some numbers. They estimated that those 13 panels on the rear two-storey extension would be able to produce up to 4000Kwh, which felt like a lot to me for an install on an East/West roof.

Does anyone have a comparable installation they could use to sense-check those numbers?

Edited by C70R on Monday 27th March 12:58

We have 41 panels directly East/West, 16.4 kW. I expect to generate around 12,500 kWh p.a. give or take 500 kWh.

This should allow you to be more accurate:

https://joint-research-centre.ec.europa.eu/pvgis-o...

FYI- Today we saw peak generation at 14 kW.

[C70R]

MaxFromage said:

C70R said:

The house is effectively T-shaped, with the T lying in perfect North-South orientation. The 'leg' of the T is a more modern two-storey extension to the rear/South (East/West pitched roof), so we decided they would put together a quote based on installing here (terracotta tiles). In total they sized up space for 13 panels, and estimated that with minimal tree coverage I should get decent returns. Through looking at our usage (we're on Octopus Go), they estimated two batteries would be sufficient to meet our needs.

I'm waiting on the full quote to land today, but having seen the survey report already I wanted to sense-check some numbers. They estimated that those 13 panels on the rear two-storey extension would be able to produce up to 4000Kwh, which felt like a lot to me for an install on an East/West roof.

Does anyone have a comparable installation they could use to sense-check those numbers?

Edited by C70R on Monday 27th March 12:58

We have 41 panels directly East/West, 16.4 kW. I expect to generate around 12,500 kWh p.a. give or take 500 kWh.

This should allow you to be more accurate:

https://joint-research-centre.ec.europa.eu/pvgis-o...

FYI- Today we saw peak generation at 14 kW.

So that sounds like their estimate is in the right ballpark at least. Thanks.

[cb31]

C70R said:

we couldn't have panels installed on the main roof of the house because it was slate.

Is this really a thing? We have a slate roof and no mention that it was a problem when we got an initial quote last year.

[dmsims]

cb31 said:

C70R said:

we couldn't have panels installed on the main roof of the house because it was slate.

Is this really a thing? We have a slate roof and no mention that it was a problem when we got an initial quote last year.

More like we don't know how or CBA

https://www.geniusroofsolutions.com/blog/solarflas...

OP I would bin them off

Edited by dmsims on Tuesday 28th March 11:18

[C70R]

dmsims said:

cb31 said:

C70R said:

we couldn't have panels installed on the main roof of the house because it was slate.

Is this really a thing? We have a slate roof and no mention that it was a problem when we got an initial quote last year.

More like we don't know how or CBA

https://www.geniusroofsolutions.com/blog/solarflas...

OP I would bin them off

Edited by dmsims on Tuesday 28th March 11:18

Sorry, my post was shorthand for "solar panels can be installed on slate roofs, but it's advisable to lift the slate and extensively modify them to do the installation, thus making it cost-prohibitive for us".

Basically the same as your link says in the section about slate installations: "You should never drill any roofing tile when installing a solar panel as it can have several negative consequences. Tiles may crack and they will lose their weather tightness causing leaks and voiding warranties."

[thecopster]

I am starting to investigate the solar option and all of options/suppliers are a bit of a mine field!

Does anyone have any recommendations in or around Bristol for companies to talk to?

Thanks

[EddyP]

I've been pondering this for about 12 months now too. The maths were a no brainer, it's a bit harder now, I've worked out at the moment I'd have around a 10 year ROI, not accounting for the interest lost on the £12k over the 10 years. But my latest bill from EON suggests that if the EPG wasn't in place the unit cost would be 63p/kwh which would make it more like a 5 year ROI.
So we've got another 12 months of the existing EPG, but then what, if only we all had a crystal ball, there is something to be said for being semi independant from the energy market.

[Gazzab]

How do you use this self generated (and stored in batteries) electricity to heat your home? If you have a traditional gas boiler and rads that is. ??

[pingu393]

EddyP said:

I've been pondering this for about 12 months now too. The maths were a no brainer, it's a bit harder now, I've worked out at the moment I'd have around a 10 year ROI, not accounting for the interest lost on the £12k over the 10 years. But my latest bill from EON suggests that if the EPG wasn't in place the unit cost would be 63p/kwh which would make it more like a 5 year ROI.
So we've got another 12 months of the existing EPG, but then what, if only we all had a crystal ball, there is something to be said for being semi independant from the energy market.

I did an ROI calculation last night. We are saving £2.50 per day based on Octopus Flexible rates, but we are on Octopus Tracker, so the saving is more like £1.70 per day. That makes our ROI between 14 and 21 years. I reckoned on 10 to 13 years when I planned the purchase. Bloody Octopus Tracker .