Solar Panels UK - is it worth it?

[Rooster6655]

Quote 3;
9.36 kW system (Estimated generatiing 6,900kW pa)
24x 390w Trina vertex S
24x optimisers (£100 ea)
1x SE 5000H inverter
10kW SE battery
Smart water diverter
Scaffolding, electrical and labour.
£35,350

- 10kW SE battery is coming in quoted as £9,620 - £9,800 with connection kit.
£6,000 for the panels.
£2,400 for the scaffolding
£2,400 for the inverter
£3,000 for the panel installation
£4,000 for the panel mounting kit.


Quite an eye watering quote that one !

Seems like a major case of making huge profits on the parts, then adding an installation charge on top too, avoid whoever these jokers are, a simple search shows that the panels would be under £4k ex vat and the inverter £800 ex vat, imagine they had to charge VAT on your quote as well that would make it £42k!

 

[RedMod3]

Seems like a major case of making huge profits on the parts, then adding an installation charge on top too, avoid whoever these jokers are, a simple search shows that the panels would be under £4k ex vat and the inverter £800 ex vat, imagine they had to charge VAT on your quote as well that would make it £42k!

My installer quotes £1,000 per kW of solar, installed, unless really extenuating circumstances.

Hopefully, by the end of this year we will have 9kW net solar and 3 Tesla Powerwalls looking after our all-electric place with air-air sourced heat pumps - with a corresponding sub £1,000 annual energy bills at the latest tariffs.

We would never have untaken our project at those hight rates as the business case would not have made sense.

Remember, zero VAT if any order includes solar panels.

 

[WannabeOwner]

Remember, zero VAT if any order includes solar panels.

There is some zero-VAT stuff that applies to over-60s too - not sure if it would cover specifically that (PowerWall only) though.

 

[ringi]

Battery may not be the best solution for HP when you get to it (utilisation only part of the year

That why I assume it needs PV to justify the battery that is needed to make a heatpump a reasonable option. However Octopus Flux gives a better set of rewards if the heatpump is not installed.

 

[RedMod3]

There is some zero-VAT stuff that applies to over-60s too - not sure if it would cover specifically that (PowerWall only) though.

Yes, which is why I ordered 4 panels with my first two Powerwalls.

 

[Pete UK]

Seems like a major case of making huge profits on the parts, then adding an installation charge on top too, avoid whoever these jokers are, a simple search shows that the panels would be under £4k ex vat and the inverter £800 ex vat, imagine they had to charge VAT on your quote as well that would make it £42k!

Mind “pm”ing me your installers details and what area are you in?

Sounds about the price of my quote number 2

 

[NikoV6]

Pats 10kw of DIY installed ground mount for £5400. I have noticed quotes are stupid high at the moment.

We only paid £6500 for 5kw fully installed on previous house 5 years ago!

 

[ringi]

Yet it is not practically possible to get paid for export with DIY install.

 

[NikoV6]

Yup! No MCS certificate so no export payment

Just buying more storage

 

[RedMod3]

Yet it is not practically possible to get paid for export with DIY install.

If you size your solar and battery to house consumption, why would you want to export anything? In 8 months, I've exported 2kWh of energy, while keeping running costs low. The key is, determine house consumption and solar generation per kW of panels by month and then you can calculate the optimum battery storage needed and solar for the tariffs you are considering.

 

[ACarneiro]

If you size your solar and battery to house consumption, why would you want to export anything? In 8 months, I've exported 2kWh of energy, while keeping running costs low. The key is, determine house consumption and solar generation per kW of panels by month and then you can calculate the optimum battery storage needed and solar for the tariffs you are considering.

If you want a relatively decent production in spring and autumn (which I suggest you do, as that’s pretty much half of the year) you’ll certainly be exporting in the summer.

 

[RedMod3]

If you want a relatively decent production in spring and autumn (which I suggest you do, as that’s pretty much half of the year) you’ll certainly be exporting in the summer.

Not necessarily if you essentially go off grid and when it’s 35-40°C outside, the heat pumps will work hard to keep you cool inside. My plan is for zero grid usage in the summer and off-peak only in the winter.

 

[WannabeOwner]

you’ll certainly be exporting in the summer.

I'm keen to find more summer uses ...

Air Con is one, but our house is well insulated, so we only need smell-of-oil-rag for winter heating and summer cooling. I wonder about inter-seasonal storage (as heat rather than power, presumably ... I did look into winching a concrete block up during Summer and lowering, to generate electricity, in winter. The numbers (size / weight / height) were a bit scary ...). I don't have ground source heatpump, but I saw n article suggesting that could be run in reverse to put heat into the ground during summer (which apparently doesn't migrate very far through "soil") so that extra warmth was available in Winter - i.e. for a better COP. They were installing pipes under "black asphalt" roads to gather heat in Summer

 

[Pete UK]

What are the most cost effective DC batteries that can charge up at 10kW/hr from the grid for say 30-40kW of storage?
And I assume you’d need 2x5kW inverters for that?

 

[ringi]

then you can calculate the optimum battery storage needed and solar for the tariffs you are considering

Now tell me what the tariffs will be like next year and for the next 20 years.....

 

[RedMod3]

Now tell me what the tariffs will be like next year and for the next 20 years.....

My assumption is solar provides all April to September and 4-hour offpeak rate is 1/3 of peak rate. Thats how I did my business case.

 

[ringi]

I not convinced offpeak will remain that low, but I am assuming evening supper peak will remain a lot more costly then other times.

The question is do I size solar to provide all power March to October rather then April to September.

 

[WannabeOwner]

I not convinced offpeak will remain that low

If there is over production there will be low rates, similar with peak-usage rates. My expectation is Time-of-Use rates ... so anyone with battery / EV can fill up during cheap periods, and avoid use during expensive ones.

I think most likely will be a day time cheap rate - when we have loads of wind and solar producing at same time - quite possibly that will be a negative rate

 

[WannabeOwner]

The question is do I size solar to provide all power March to October rather then April to September.

Or find a use for over production of PV in Summer maybe?

 

[Mrklaw]

I really hope EON pull their finger out soon - we’re getting occasional days where my lowly array is producing spikes I can’t use, I need that battery and extra solar.

Will chase again but never get anything other than a ‘computer says wait’ generic feeling CS response. Signed the damn contract in July last year!