Solar Panel Quote - Nottinghamshire

milkybargeek

Hi All 

I'm looking at a Solar + Battery setup for a 5 bed detached house (50 degrees SW and 40 degree roof), with the hope of reducing my electricity bill and going greener!

Currently, the estimated usage for Electricity is 8727KW (Including car charging) and we're on Octopus Go, so nightly charging rate of 5p per KW (currently).

I'm now considering the best route forward. EON state we'd only get 11 panels on the roof, whereas the sole trader is stating 17 (I noticed a bit of difference in the size of panels but, nothing major). EON also offer interest-free for 3 years; which is a bonus.

However, what questions should I be asking next?
How can I weigh up the savings I could make factoring in the battery charge at night?
Do I ask EON to see if they can match the panels or get closer to it?
What price per KW, is good when factoring a battery in?

Any other suggestions are welcome.


Current quotes we have:

EON (Roof design below)
1 - Solis 1-phase inverter + 11 x Trina Solar 385W Panels = £5,537.97
Solar Generation  3,511 kWh) (£1.58 per KW)

2 - GivEnergy Hybrid inverter with 5.2 kWh battery + 11 x Trina Solar 385W Panels = £8,498.19
Solar Generation  3,511 kWh (£2.42 per kw) 

3 - GivEnergy Hybrid inverter with 8.2 kWh battery (8.2 kWh usable) + 11 x Trina Solar 385W Panels = £9,232.05
Solar Generation  3,511 kWh (2.62per kw) 


Sole Trader MCS Registered (Roof design not shown but, they say they can fit 17 panels)
1 - GivEnergy Hybrid inverter with 8.2 kWh battery (8.2 kWh usable) + 17 x QCell Q.Peak Duo BLK-G9+ 340w Mono All Black = £10,300
Solar Generation 4,768 Kwh (£2.15 per kw)

The third quote also stated payback to begin in year 8, as we have the ability to charge the battery at a low rate at night, saving more £££.

Spies

Interesting on the EON quote, when I got a quote, they could only offer 330w panels!

QrizB

It will also be interesting to see how your independent installer expects to fit 17 panels on that roof!

milkybargeek

QrizB said:

It will also be interesting to see how your independent installer expects to fit 17 panels on that roof!

Thanks, I'll ask for a plan from the independent installer. Are they bound by any rules to leave a gap around the edge?

QrizB

milkybargeek said:

QrizB said:

It will also be interesting to see how your independent installer expects to fit 17 panels on that roof!

Thanks, I'll ask for a plan from the independent installer. Are they bound by any rules to leave a gap around the edge?

You're meant to leave a gap to reduce the chance of the wind getting in behind them and pulling them off the roof. Different mounting systems (and different panels) may have different requirements. From memory 300mm all around is a common one.

Merlin139

The Dimensions of the Q Cell G9+ are 1673 x 1030mm

The Dimensions of the Trina Solar are 1754 x 1096mm

If your diagram is to scale I cannot see how you could get another 6 panels on the roof unless they are putting them on another side.

The wholesale price of 17 Q Cell panels and 8.2 kWh Hybrid inverter with battery is around £6100 plus VAT. 

The wholesale price of 11 Trina and 5.2 kWh Hybrid inverter with battery is around £4300 plus VAT.
The wholesale price of 11 Trina and 8.2 kWh Hybrid inverter with battery is around £5100 plus VAT.

Spies

The first guy I had look at my roof gave me a completely unrealistic estimate as well, reckoned I'd get 9 on one of my elevations that now has been quoted by different people for 6...

milkybargeek

Merlin139 said:

The Dimensions of the Q Cell G9+ are 1673 x 1030mm

The Dimensions of the Trina Solar are 1754 x 1096mm

If your diagram is to scale I cannot see how you could get another 6 panels on the roof unless they are putting them on another side.

The wholesale price of 17 Q Cell panels and 8.2 kWh Hybrid inverter with battery is around £6100 plus VAT. 

The wholesale price of 11 Trina and 5.2 kWh Hybrid inverter with battery is around £4300 plus VAT.
The wholesale price of 11 Trina and 8.2 kWh Hybrid inverter with battery is around £5100 plus VAT.

Thanks, for complete install how much would you expect to pay on top. With scaffolding and labour etc...

arty688

If you take out the battery say for 8.2kw Givenergy £3.5k then you should be aiming for £1 Kw . I guess though in the current climate prices are only going one way.
I would get an online quote or 2 where they use google earth and see what they come back with. I would alway guess that EON will be expensive and interest free usually means interest is included in the cost.

the 17 panels , maybe 1 more on each row and 4 along the top horizontally ? 

isvana

I suspect the independent supplier is using landscape orientation for the panels to fit in another few panels. I would have thought though the extra cost of >370W panels would be justified, unless the smaller size of the 340W panels is required to get the extra panels. 

milkybargeek

arty688 said:

If you take out the battery say for 8.2kw Givenergy £3.5k then you should be aiming for £1 Kw . I guess though in the current climate prices are only going one way.
I would get an online quote or 2 where they use google earth and see what they come back with. I would alway guess that EON will be expensive and interest free usually means interest is included in the cost.

the 17 panels , maybe 1 more on each row and 4 along the top horizontally ? 

If I take off the Givenergy Battery it still leaves the inverter which compared to a Solis inverter is more expensive. Or are you saying take the inverter and battery off to get to the £1 per KW?