Complete beginner looking for some basic pointers

[Timj_1]

Hi - I am looking to create a PV system for my domestic property 3 bed semi. On checking with my smart meter it looks like I use around 12Kw a day with a peak of around 5Kwh in terms of load. I have a shade free roof facing due South and room for battery storage. My peak demand is early morning and early evening with little during sunshine hours so I am guessing storage is going to be key.

Quick initial research yields

Grid tie inverter to use PV/battery and take power from the grid when I need to top up ie battery is low or no sun? Also manage battery charging from PV when no load? Am I right with this - basically want to use as little mains as I can using PV and battery for close to all power but with grid for backup?

If this is correct could someone kind and knowledgeable point be to the best inverters, batteries and PV units.

Re batteries I have seen 7000 deep cycle bats for around £300 a KWH - might be optimistic on that!

On inverters looked at Sunny Boy storage 5K

Many thanks in advance

Kindest Tim

 

[Sharpend]

Have you had a read around the site? We have had an influx of solar queries recently with many people looking to do what you propose, so to save the authors of the advice from endlessly repeating themselves it would be beneficial if you had a rummage around then asked specific questions as the answers you are seeking are already within!


Note to moderators, would it be worthwhile having our solar experts do a brief which could be posted as a sticky so all can reference at the head of the forum?

 

[Timj_1]

Thanks just doing this as I write.

 

[Timj_1]

Hi - I am looking to create a PV system for my domestic property 3 bed semi. On checking with my smart meter it looks like I use around 12Kw a day with a peak of around 5Kwh in terms of load. I have a shade free roof facing due South and room for battery storage. My peak demand is early morning and early evening with little during sunshine hours so I am guessing storage is going to be key.

Quick initial research yields

Grid tie inverter to use PV/battery and take power from the grid when I need to top up ie battery is low or no sun? Also manage battery charging from PV when no load? Am I right with this - basically want to use as little mains as I can using PV and battery for close to all power but with grid for backup?

If this is correct could someone kind and knowledgeable point be to the best inverters, batteries and PV units.

Re batteries I have seen 7000 deep cycle bats for around £300 a KWH - might be optimistic on that!

On inverters looked at Sunny Boy storage 5K

Many thanks in advance

Kindest Tim

Edit - also wondering if I should look around to see if feedin tariffs are worth pursuing in the UK?

 

[Sharpend]

Unlikely but I’ll leave those with more knowledge than I to advise.

 

[binky]

Edit - also wondering if I should look around to see if feedin tariffs are worth pursuing in the UK?

there are no FiTs anymore, but some companies offer SEG - a payment for exported leccy.

 

[Murdoch]

Having white goods with delay start timers really helps your use of solar, as does, if you have a hot water tank, a diverter so you get free hot water.

ive got solar and a diverter for the hot water.

as yet I’m not convinced about batteries, so do your sums carefully and also there will be many autumn, winter and spring days where generation will be low

 

[Murdoch]

FYI Last year, month by month totals were

J 71
F166
M 293
A 484
M 427
J 454
J 477
A 375
S 339
O 225
N 131
D 54

 

[Andy1733]

Hi - I am looking to create a PV system for my domestic property 3 bed semi. On checking with my smart meter it looks like I use around 12Kw a day with a peak of around 5Kwh in terms of load. I have a shade free roof facing due South and room for battery storage. My peak demand is early morning and early evening with little during sunshine hours so I am guessing storage is going to be key.

Quick initial research yields

Grid tie inverter to use PV/battery and take power from the grid when I need to top up ie battery is low or no sun? Also manage battery charging from PV when no load? Am I right with this - basically want to use as little mains as I can using PV and battery for close to all power but with grid for backup?

If this is correct could someone kind and knowledgeable point be to the best inverters, batteries and PV units.

Re batteries I have seen 7000 deep cycle bats for around £300 a KWH - might be optimistic on that!

On inverters looked at Sunny Boy storage 5K

Many thanks in advance

Kindest Tim

hi Tim.

Hi - I am looking to create a PV system for my domestic property 3 bed semi. On checking with my smart meter it looks like I use around 12Kw a day with a peak of around 5Kwh in terms of load. I have a shade free roof facing due South and room for battery storage. My peak demand is early morning and early evening with little during sunshine hours so I am guessing storage is going to be key.

Quick initial research yields

Grid tie inverter to use PV/battery and take power from the grid when I need to top up ie battery is low or no sun? Also manage battery charging from PV when no load? Am I right with this - basically want to use as little mains as I can using PV and battery for close to all power but with grid for backup?

If this is correct could someone kind and knowledgeable point be to the best inverters, batteries and PV units.

Re batteries I have seen 7000 deep cycle bats for around £300 a KWH - might be optimistic on that!

On inverters looked at Sunny Boy storage 5K

Many thanks in advance

Kindest Tim

Hi Tim. I'm new to solar PV this year. This forum have been very helpful though most are professional electrition and expect you to know the basics and sometimes the replays can seem harsh ... Regards your post.
12kw daily use seems a little low. I'm in SIM property and a low ish user around 20kw.
Battery's are rare ATM due to supply and demand. I've just back ordered pylontech which said 1st July delivery, now pushed back to 22nd August.
Are you installing the solar yourself or a company? If you are installing yourself you won't get the payback as the install needs to have MSC cert.
If you are installing yourself then you will need to either pre apply for a g99/g100 form from your local DNO. If you install under 3.6kw inverter you install and then complete the g98 form with your local DNO.

 

[Chrisbee]

I'm very very pleased with a Solis RHI-3.6K-48ES-5G 3.6kW Hybrid inverter fed by 4.55kWp of panels and 4.8kWh of Pylontech US2000C batteries.

Because mine was installed by a MSC installer I can get payment for any power that goes back to the grid. But the best rate I could find is 5.5p/kWh.
So the name of the game is still to use everything that's generated.

Having batteries means there's somewhere for excess power to go when the sun is out, and there's a source of power whenever a cloud comes across.

We use around 20kWh a day. There's always some background draw even through the night. We find our batteries usually last well into the evening but are always empty by morning, when the daily cycle starts again.

Oh, we're retired and home all day. Which makes a big difference to how much and when power is used.

If we didn't have batteries then a diverter to send excess into an immersion heater would be very beneficial. We have one, but it only tends to kick in late in the day, on e the batteries are full. So it doesn't contribute much towards our hot water.

 

[binky]

At 5.5p how long does it take to payback the cost of an MCS installer? This is why DiY is becoming very popular, if you have the skills

 

[monkey5]

At 5.5p how long does it take to payback the cost of an MCS installer? This is why DiY is becoming very popular, if you have the skills

Is it worth doing a self install then, what sort of price wise different is it? Never had anything to do with solar but happy to learn if it'll save me a few quid

 

[Andy1733]

Is it worth doing a self install then, what sort of price wise different is it? Never had anything to do with solar but happy to learn if it'll save me a few quid

I was quoted £8500 just before Xmas for a 6kw system with 3 x 3.5kw pylontech batteries install and sign off. Not sure what this would be now as when I tried to contact the company they never returned my emails and website said no longer taking orders due to high demand
I priced the materials to match the above quote and it was just over 6k.
I then got a quote for supply only of a 4kw system at £5200 1 X 4.8kw battery
.
I used the spec from the 2nd quote and shopped around to buy same materials but at best price so saved £518
Ive installed the 4kw setup with 4.8kw battery (when it arrives) for total £4682. Over the past 11 days I've generated between 12.4kw lowest and 18.7kw. highest.
From this amount I've used approx 8-10kw and rest gone back to the grid.

 

[binky]

I was quoted £8500 just before Xmas for a 6kw system with 3 x 3.5kw pylontech batteries install and sign off. Not sure what this would be now as when I tried to contact the company they never returned my emails and website said no longer taking orders due to high demand
I priced the materials to match the above quote and it was just over 6k.
I then got a quote for supply only of a 4kw system at £5200 1 X 4.8kw battery
.
I used the spec from the 2nd quote and shopped around to buy same materials but at best price so saved £518
Ive installed the 4kw setup with 4.8kw battery (when it arrives) for total £4682. Over the past 11 days I've generated between 12.4kw lowest and 18.7kw. highest.
From this amount I've used approx 8-10kw and rest gone back to the grid.

Many installers are charging £2k and more for installation. Plus they get the materials cheaper, and can claim 15%vat back on materials. Having seen some prices quoted recently, I was thinking of coming out of retirement from the solar industry

 

[Chrisbee]

My installer only charged 5% VAT.

 

[binky]

My installer only charged 5% VAT.

yes, but we get charged 20% on materials and claim 15% back. Most installers don't pass that on as we have to wait upto 3months for the vat return.

 

[Andy1733]

My installer only charged 5% VAT.

Chris. May I be rude and ask,. We have similar systems and my cost was £4682. How does this compare to you installation

 

[Chrisbee]

Andy, mine was just over £7K so that's a massive saving if you can do it yourself.

Having said that, prices of equipment seems to be going up by the minute.

(I also had quotes from large national companies for a similar price but without batteries).

I will be looking at suppliers like Octopus energy once my fixed tarrifs run out. Hopefully I can do far better than 5.5p by using their half hourly rates. (Not that I understand anything about those yet)

 

[Andy1733]

Andy, mine was just over £7K so that's a massive saving if you can do it yourself.

Having said that, prices of equipment seems to be going up by the minute.

(I also had quotes from large national companies for a similar price but without batteries).

I will be looking at suppliers like Octopus energy once my fixed tarrifs run out. Hopefully I can do far better than 5.5p by using their half hourly rates. (Not that I understand anything about those yet)

Thanks Chris. It looks a massive saving ATM but down the line your payback will balance it out a bit more. Don't forget I didn't have scaffolding to pay for as it went on my garage roof
If you sell 40- 50p a day back to the grid over 10 years it would balance it out.
Tbh I'm happy to be saving even if it's a few hundred per year. I'm a Yorkshire man, I hate giving money away

 

[Chrisbee]

I'm not a Yorkshire man but I still hate giving money away.

With being home all the time we seem to be able to use almost anything we generate. That's yet another consideration.

It is what it is though, now. I certainly couldn't have done any work on the roof.
I'm projecting a 7 year payback at the moment, although I don't have a whole years data.
That's calculated with a current grid cost of 21.5p/kWh. As prices go up that will get shorter and shorter.