Solar panels and battery - any real world reccomendations?

94JDH said:
I'm sure I read somewhere it was able to check the forecast? I'll have a look.
Click to expand...

With super cheap electric it's less important. My PW2 is saving me 50p a day by not charging due to the sunny forecast. If overnight electric ever got more expensive that intelligence will be more valuable.
 
Quick question. We have been looking at solar panels for a while but I am still confused as to thew size of battery that we should get. For example, if we had a 5.07 kWp system (which the company estimate will produce 4046 kW/h per annum), what size battery do we need?

Is it a battery that can absorb the total panel output, or do we go larger and have one that can absorb unused output but also take Octopus Go overnight rates as well?
 
gailjon said:
Quick question. We have been looking at solar panels for a while but I am still confused as to thew size of battery that we should get. For example, if we had a 5.07 kWp system (which the company estimate will produce 4046 kW/h per annum), what size battery do we need?

Is it a battery that can absorb the total panel output, or do we go larger and have one that can absorb unused output but also take Octopus Go overnight rates as well?
Click to expand...

Solar array size is mutually exclusive, and you shoudl be looking to pair your battery with the energy you use when the sun isn't out. ie bigger battery that can be charged during day if you have excess or at night using cheaper rates.
 
Its very complicated. How much energy do you use, when do you use it, can you move it to benefit from when a battery is charged to use that as the source?

The battery can be as big or small as you want/need, the determining factor of how fast it can absorb energy from solar panels will be inverters, and their specs? If you went up to say a 10kW PV array, an inverter may still only charge the batteries at 3/4/5kW.

Basically, bigger is always better. More solar PV panels=more chance you'll generate significant energy in winter. Bigger battery (to I suppose about your daily/twice daily usage) so you can charge those batteries for free from solar or cheap overnight rates and then use it when the sun isnt out and its not cheap overnight. Bigger inverter ratings so you charge the batteries quicker with a big solar array, and can also supply the house with more power at once too.
 
1pudding1 said:
Its very complicated. How much energy do you use, when do you use it, can you move it to benefit from when a battery is charged to use that as the source?

The battery can be as big or small as you want/need, the determining factor of how fast it can absorb energy from solar panels will be inverters, and their specs? If you went up to say a 10kW PV array, an inverter may still only charge the batteries at 3/4/5kW.

Basically, bigger is always better. More solar PV panels=more chance you'll generate significant energy in winter. Bigger battery (to I suppose about your daily/twice daily usage) so you can charge those batteries for free from solar or cheap overnight rates and then use it when the sun isnt out and its not cheap overnight. Bigger inverter ratings so you charge the batteries quicker with a big solar array, and can also supply the house with more power at once too.
Click to expand...

That's why for my system I've gone for 2 batteries and 2 inverters to maximize storage of 7.2kW array and also maximize the charge on night rate for winter periods. Additional benefits being 2x3.6kW discharge rate if demand from house needs it.
 
Very good solar weather last couple of weeks. The rental property with only a 3.5kw system, 19-31March inclusive(13days)
generated 209KW, really good for March and considering there is another good 6 months of solar generation.

2014 install date, receives FIT payments of just over 20p a unit, the 13 days have earned £42.
 
Ron-ski said:
Third best March for me, 2022 was 390kWh, 2017 was 397kWh and the best 2020 was 430kWh, with a 4kw system.

Best month ever since install in December 2015 was May 2020 with 712.5kWh.
Click to expand...

2020 was crazy. That was the start of lockdown. That 3 month period was my best as well.

mar - 441
apr - 583
may - 708
 
My installer has said the wait for a GivEnergy battery and inverter could be as long as November and recommended Huawei.

‘Does anyone has experience of Huawei for solar kit?
 
SDK^ said:
My installer has said the wait for a GivEnergy battery and inverter could be as long as November and recommended Huawei.

‘Does anyone has experience of Huawei for solar kit?
Click to expand...
I hope that's not true -going to be a lot of disappointed customers.
 
Hi all, this thread has been super useful in my research, thank you. I'm wondering if anyone has any thoughts on my plans?:

We live in the SE near London, 6 bedroom house, south facing garden. Conventional gas HW and CH, we use about £1.50-£3 of electricity a day (can't provide annual estimates as haven't had a bill since Avro went bust last year, have been chasing...) Gas has been about £3-7/day through this winter.

I would like to use the immersion via Iboost or similar to reduce gas useage but I'll look into that once I have an idea of what I am feeding back to the grid. We'd go on the Octopus Go tariff and I would force charge the batteries overnight when PV fails to fill them. We are about to order an EV which will live at home during the day most of the time so I could trickle charge that off the PV but I doubt there will be any power left after the house and immersion demand so that will probably be set on the cheap 4 hour overnight GO rate.

We are close to pulling the trigger on this system:
  • PV: 14x JA Solar 395w Percium Half-Cell All Black
  • Optimisers: 14x Solar Edge S500
  • Inverter: Solar Edge 3.68 HD Wave
  • Bird Prevent Mesh (+£750 :s damn wood pigeons!)
And
  • Charge Controller: Solis 3.0 RAI AC coupled
  • Storage: 2x Pylontech US3000 3.5kWh Li-Ion Battery
Price is circa £13,750. I like the company having spoken with several and met with two now. They are no longer taking new orders from people who call them at the moment such is demand, so zero room for discounts.

The SolarEdge system and the need it creates for a seperate charge controller is adding about £2,500 to the price, the issue is that I have dormers and and trees about.

South Array
Proposed System Rating ( kWp ) 2.77 kWp
Postcode Region Region 1
Array Orientation S/E 0 Degrees
Pitch of Mount 35 Degrees
Over Shading Factor Factor 0.95
Estimated Solar Radiation 934 kWh / Annum
Estimated Annual System Output Using MCS Standard Procedure 2,587 kWh / Annum

West Array
Proposed System Rating ( kWp ) 2.77 kWp
Postcode Region Region 1
Array Orientation S/E 90 Degrees
Pitch of Mount 35 Degrees
Over Shading Factor Factor 1.0
Estimated Solar Radiation 783 kWh / Annum
Estimated Annual System Output Using MCS Standard Procedure 2,169 kWh / Annum

I am having some second thoughts on the cost vs my current annual electricity useage which isn't all that much.
House is about as well insulated as is possible for a 1980s home that has been retrofitted (cavity wall insulation, 50mm kingspan added above ground floor beam and block 150mm kingspan in roof.

I would welcome all and any comments, thanks very much.
 
SBo said:
Hi all, this thread has been super useful in my research, thank you. I'm wondering if anyone has any thoughts on my plans?:

We live in the SE near London, 6 bedroom house, south facing garden. Conventional gas HW and CH, we use about £1.50-£3 of electricity a day (can't provide annual estimates as haven't had a bill since Avro went bust last year, have been chasing...) Gas has been about £3-7/day through this winter.

I would like to use the immersion via Iboost or similar to reduce gas useage but I'll look into that once I have an idea of what I am feeding back to the grid. We'd go on the Octopus Go tariff and I would force charge the batteries overnight when PV fails to fill them. We are about to order an EV which will live at home during the day most of the time so I could trickle charge that off the PV but I doubt there will be any power left after the house and immersion demand so that will probably be set on the cheap 4 hour overnight GO rate.

We are close to pulling the trigger on this system:
  • PV: 14x JA Solar 395w Percium Half-Cell All Black
  • Optimisers: 14x Solar Edge S500
  • Inverter: Solar Edge 3.68 HD Wave
  • Bird Prevent Mesh (+£750 :s damn wood pigeons!)
And
  • Charge Controller: Solis 3.0 RAI AC coupled
  • Storage: 2x Pylontech US3000 3.5kWh Li-Ion Battery
Price is circa £13,750. I like the company having spoken with several and met with two now. They are no longer taking new orders from people who call them at the moment such is demand, so zero room for discounts.

The SolarEdge system and the need it creates for a seperate charge controller is adding about £2,500 to the price, the issue is that I have dormers and and trees about.

South Array
Proposed System Rating ( kWp ) 2.77 kWp
Postcode Region Region 1
Array Orientation S/E 0 Degrees
Pitch of Mount 35 Degrees
Over Shading Factor Factor 0.95
Estimated Solar Radiation 934 kWh / Annum
Estimated Annual System Output Using MCS Standard Procedure 2,587 kWh / Annum

West Array
Proposed System Rating ( kWp ) 2.77 kWp
Postcode Region Region 1
Array Orientation S/E 90 Degrees
Pitch of Mount 35 Degrees
Over Shading Factor Factor 1.0
Estimated Solar Radiation 783 kWh / Annum
Estimated Annual System Output Using MCS Standard Procedure 2,169 kWh / Annum

I am having some second thoughts on the cost vs my current annual electricity useage which isn't all that much.
House is about as well insulated as is possible for a 1980s home that has been retrofitted (cavity wall insulation, 50mm kingspan added above ground floor beam and block 150mm kingspan in roof.

I would welcome all and any comments, thanks very much.
Click to expand...


Just a quick comment on price, have they removed the VAT for you as per the new incentives? If not will save you around £650?
 
Yes they have, 0 VAT on there.

This is the output of the estimate on the energy saving trust website. It doesn't factor in the battery's role:

Potential annual benefit£545
Potential CO2 saving982 kg / year
Potential fuel bill saving£433 / year
Potential payments from SEG
(at 4.1 p/kWh)£112 year
Potential lifetime benefit£13,190
 
You must log in or register to reply here.
Back
Top Bottom