Integrated Solar PV or not?

[joth]

On 11/03/2021 at 12:03, ProDave said:

I believe it is only financially viable if you can buy the kit cheap and install it yourself.

So when is relandscaping a garden or installing a swimming pool financially viable? Things are financially viable when the purchaser has the finances available to purchase it. End of.

I think you mean economically justifiable, which is not always the reason to decide to make a modification to a home. Especially those with zero payback like putting in a hot tub or enlarging the patio.

 

To give another view - we put a whole roof of solar on our house (GB sol RIS, picture attached) cost about 16k£ but the whole enerphit+ renovation has added double the value onto our house that it cost to do, undeniably in part due to the current crazy market, but in part because interest in sustainable designed houses are suddenly on the up* in our area and nothing signals this more clearly than a whole roof of solar (in a conservation area where this was not permitted a couple years ago). This is not going to be the common case I know, but done well I do see even the economic  value being more than just the reduced electric bill.

 

* I was very surprised - the estate agents we spoke to this week knew very well what a passive House is; turns out in large part because customers are taking about ours as a reference point for the area. 

 

 

 

 

Edited June 13, 2021 by joth

[Bitpipe]

23 minutes ago, joth said:

* I was very surprised - the estate agents we spoke to this week knew very well what a passive House is; turns out in large part because customers are taking about ours as a reference point for the area. 

 

That is a surprising change - previous experience was that passive or 'eco' house deterred run of the mill buyers as it suggested a compromised lifestyle for occupants or lots of complex tech to manage.

 

 

[Gone West]

14 hours ago, Bitpipe said:

 

That is a surprising change - previous experience was that passive or 'eco' house deterred run of the mill buyers as it suggested a compromised lifestyle for occupants or lots of complex tech to manage.

 

 

When we recently sold our PH the estate agent admitted he found it difficult to value because there are so few around. We had a lot of interest and we had had offers straightaway. We ended up with three lots of buyers who all wanted to buy it because it was a PH. They were bidding against each other and it ended up selling for substantially more than the asking price. The asking price was more than my own valuation. I suspect the Stamp Duty holiday was a major factor in the large number of buyers.

[Mr Punter]

1 hour ago, Gone West said:

When we recently sold our PH the estate agent admitted he found it difficult to value because there are so few around. We had a lot of interest and we had had offers straightaway. We ended up with three lots of buyers who all wanted to buy it because it was a PH. They were bidding against each other and it ended up selling for substantially more than the asking price. The asking price was more than my own valuation. I suspect the Stamp Duty holiday was a major factor in the large number of buyers.

 

All house prices have risen around here.  There are more buyers than sellers and most of what is on the market is either crap or sells straight away.

[joth]

On 14/06/2021 at 10:12, Mr Punter said:

 

All house prices have risen around here.  There are more buyers than sellers and most of what is on the market is either crap or sells straight away.

 

I got a bit more granularity on the valuation (from the Estate Agent that sold it to us 3 years ago),

Of the estimated 80% increase in value, aprx 20% is from market increases and 60% from the renovation+extension. The renovation cost us about 50% of the purchase price, thus we've made 10% "Profit" on the project, independent of market increases.

 

The  estate agent's included this thought: "As discussed energy efficiency is becoming more and more in the consciousness so the product will only be more in demand in the future in my opinion."

I see this too - interest in sustainability within "normal" renovation groups in our area has grown massively in the 3 years since we started the project, and  I can only see this continuing. 

 

 

[SteamyTea]

30 minutes ago, joth said:

The renovation cost us about 50% of the purchase price, thus we've made 10% "Profit" on the project, independent of market increases.

How long did the renovation/improvements take?

And did that 50% cost include things like BC fees, delivery charges, planning?

And, And, was the 10% profit on what you paid initially, or 10% of  the sale value?

Edited June 15, 2021 by SteamyTea

[joth]

1 minute ago, SteamyTea said:

How long did the renovation/improvements take?

14 months  (original estimate was 8 months; COVID added about 4 months, the rest was the usual overoptimism)

 

[SteamyTea]

2 minutes ago, joth said:

14 months  (original estimate was 8 months; COVID added about 4 months, the rest was the usual overoptimism)

 

Compared to most, that was fair rocketing along.

[Adsibob]

On 11/03/2021 at 12:03, ProDave said:

My DIY install cost me about £1500 which means it will pay for itself in 6 years.  I believe it is only financially viable if you can buy the kit cheap and install it yourself.

So how does one go about doing this? I will have scaffolding up in a couple of months when the loft is converted so good opportunity to do it, and hoping to put PV panels on my flat roof (above the dormer conversion) which is about 8.5m by 5m. Got a couple of quotes from companies that also install and it was just crazy prices. 

[TonyT]

Have a google plug in solar website

 

You don’t get FIT payments if it’s DIY

 

 

[ProDave]

There is no FIT any more, that stopped a couple of years ago.

 

"How do you do it"?  Buy some panels and some mounting hardware, fit it to your roof and pay an electrician to connect it all.

 

If it is the "standard" 3.68 kW system, you install it and then notify your DNO under the G98 procedure.  If you want more than 3.68kW output, you have to get prior approval from the DNO under the G99 procedure and there may be a charge for network upgrades before you are allowed to connect it.

[SteamyTea]

5 hours ago, Adsibob said:

hoping to put PV panels on my flat roof (above the dormer conversion) which is about 8.5m by 5m.

Are you thinking of laying the modules flat?  This may impair their performance.

[Adsibob]

55 minutes ago, SteamyTea said:

Are you thinking of laying the modules flat?  This may impair their performance.

No, I was hoping to get those moving mounts that track the path of the sun as the back of the house faces west and the front of the house east. Not sure if they are expensive though.

[Marvin]

8 hours ago, Adsibob said:

No, I was hoping to get those moving mounts that track the path of the sun as the back of the house faces west and the front of the house east. Not sure if they are expensive though.

 

Well my guess is that if they were cheap everyone would have them.

I think they would not work on a pitched roof.

 

I'll let the more knowledgeable plough in with all the technical reasons.

 

Good luck.

 

Marvin

 

[SteamyTea]

7 minutes ago, Marvin said:

I'll let the more knowledgeable plough in with all the technical reasons.

Mass and wind loading are the two things that I can think of, this would mean you need a reinforced roof.

A sketch of the roof would help.

[Adsibob]

It’sa flat roof, ie the lid of a dormer. Hasn’t been built yet, so possibly time to reinforce it if necessary. 

[SteamyTea]

3 minutes ago, Adsibob said:

It’sa flat roof, ie the lid of a dormer. Hasn’t been built yet, so possibly time to reinforce it if necessary. 

There are shading issues to consider. Tracking systems are usually used in fields where the modules are spaced apart, so when the sun is below peak altitude, one module does not cast a shadow on another.

Shading is the killer for PV performance.

You could consider putting a fall on the roof, say 15⁰, this is to let rain flow away and take the buildup of dirt with it.

But you still have to be wary of shadows caused by the roof ridge, and nearby buildings.

This may be a case where individual module inverters work well.

A sketch would help.

[Adsibob]

4 hours ago, SteamyTea said:

You could consider putting a fall on the roof, say 15⁰, this is to let rain flow away and take the buildup of dirt with it.

But you still have to be wary of shadows caused by the roof ridge, and nearby buildings.

This may be a case where individual module inverters work well.

A sketch would help.

Thanks @SteamyTea, here are some drawings. The first drawing shows part of the roof plan. The dimensions are about 8.2m by 3.15m; I'd forgotten we had to make the dormer slightly smaller - for reasons I won't go into to). The ridge line is centred with the chimney stack (shown as a rectangle with 8 circles in it). The second drawing shows a cross section. You can see the pitch of the small piece of pitched roof between the flat roof and the ridge line is 45 degrees. But the diagonal length of that bit of roof (i.e. the hypotenuse on the cross section) is only about a metre, so I'm hoping there won't be much shading from that. Obviously the chimney stack will cause a bit of shade, but there isn't much we can do about that as we use it and it is also jointly owned by our semi detached neighbours.

 

 

 

 

Edited July 3, 2021 by Adsibob

[SteamyTea]

I think you would have a highly compromised PV system.

You may be better off, and this may sound odd, with a ST because when the sun does hit it, they can deliver a lot of power. So may well contribute to water heating more.

An ST system can be fixed at an optimal angle and will be smaller overall. Though a simple ASHP dedicated to DHW may be more cost effective overall. 

[Adsibob]

10 minutes ago, SteamyTea said:

I think you would have a highly compromised PV system.

You may be better off, and this may sound odd, with a ST because when the sun does hit it, they can deliver a lot of power. So may well contribute to water heating more.

An ST system can be fixed at an optimal angle and will be smaller overall. Though a simple ASHP dedicated to DHW may be more cost effective overall. 

I'm not keen on ASHP because of the noise and unsightlyness of them and the requirement in our area to get planning permission for them. A solution to most of these problems is to go with a super expensive unit like an Oschner, but even then they require a lot of space for the internal compressor which we didn't really have unless we severely compromised our utility room. Next house.

The Solar Thermal idea however might work quite well for us. How much do you think that would cost? We have quite high hot water requirements (our UVC is going to be either 300L or 400L in size).

[SteamyTea]

4 minutes ago, Adsibob said:

I'm not keen on ASHP because of the noise and unsightlyness of them

Won't be as unsightly as an PV and ST set at an angle on your flat room.  The noise issue is just not there on modern ones.  Planning should not refuse it if follow the MCS installation guidance, the government has set a target to install 600,000 of them a year.

 

5 minutes ago, Adsibob said:

The Solar Thermal idea however might work quite well for us. How much do you think that would cost?

I would have thought that you could get a tip top system for a couple of thousand.  Just hunt around on eBay to see what the component parts cost.  They do take annual maintenance