Solar Panel Advice (Wirral)

SherriRuffles

[Deleted User] said:

I would get a quote from at least one other installer. I would recommend GenFit Solar, Chester. MyEnergi UK are now offering a battery solution.

Hi Dolor, had a quote from Genfit just on 14K 

joe956

Whatever you choose avoid GivEnergy kit (and the company) - I am unfortunate owner of their inverter and battery and all we have is problems. Just look at trustpilot and search for givenergy.

Min1234

Hi all, just had my first quote for solar panel and wanted to check with the members here for their views please as I feel out of my depth here. 

Details of quote: 
Nominal 7.4kWp (18 panel) solar PV sytem, using premium, high efficiency panels (TRINA VERTES DE09R.05-410)

Vertex 410W all-black panels with a high quality Solis 6kW inverter (PV INVERTER - SOLIS GR1P-S6-6K)
MOUNTING KIT - RENUSOL
BOS - SWITCHING, CABLE, METER, MONITORING (£467 quoted for this - no idea if meter is 1st or 2nd gen)
BIRD-PROOF MESHING
TOTAL COST INCLUSIVE OF installation and scaffolding comes to £7000
I have been told Solaredge optimiser is better than Solis, but if I go for it, it will add circa £1,000 to the quote.

In terms of battery storage, adding an AC coupled Givenergy storage system with 3kW inverter and 5.2kWh would cost almost £3k and with 9.5kWh battery around £4.5k. I have been told this can be added in future, but if affordable now, it's best to do at same time as install of solar panels as that will mean no VAT applies to the battery.

I mentioned to the contractor that I intend to get underfloor heating and was told that this is likely to be a plumbed system so the solar PV will help only if a heat pump is used, rather than a system boiler. However, either way, if a HW cylinder is incorporated, it will be fitted with an immersion as standard (usually) and surplus solar energy, otherwise exported, can be sent to the element to help heat the water.

The solar pv system quoted is estimated to generate around 6000kWh a year, which averages 16kWh a day, but obviously that will be lower in winter and higher in summer, perhaps over 40kWh on a good day (quote shows a monthly estimate chart). So a 5.2kWh battery is quite small for the solar but would act as a buffer for intermittent generation and demand during the day, and provide stored energy for the evening. Depending on consumption, that may be all the capacity needed, but it can be added to later on.

I am inclined to go ahead as advised by the contractor, but im conscious there is a lot in the quote I dont truly understand so just wanted to put this out there to unconnected parties so I can become aware if I am missing something or should be asking for something different or more clarification. 

Would welcome any thoughts / advice regarding the above. 

markin

Min1234 said:

Hi all, just had my first quote for solar panel and wanted to check with the members here for their views please as I feel out of my depth here. 

Details of quote: 
Nominal 7.4kWp (18 panel) solar PV sytem, using premium, high efficiency panels (TRINA VERTES DE09R.05-410)

Vertex 410W all-black panels with a high quality Solis 6kW inverter (PV INVERTER - SOLIS GR1P-S6-6K)
MOUNTING KIT - RENUSOL
BOS - SWITCHING, CABLE, METER, MONITORING (£467 quoted for this - no idea if meter is 1st or 2nd gen)
BIRD-PROOF MESHING
TOTAL COST INCLUSIVE OF installation and scaffolding comes to £7000
I have been told Solaredge optimiser is better than Solis, but if I go for it, it will add circa £1,000 to the quote.

In terms of battery storage, adding an AC coupled Givenergy storage system with 3kW inverter and 5.2kWh would cost almost £3k and with 9.5kWh battery around £4.5k. I have been told this can be added in future, but if affordable now, it's best to do at same time as install of solar panels as that will mean no VAT applies to the battery.

I mentioned to the contractor that I intend to get underfloor heating and was told that this is likely to be a plumbed system so the solar PV will help only if a heat pump is used, rather than a system boiler. However, either way, if a HW cylinder is incorporated, it will be fitted with an immersion as standard (usually) and surplus solar energy, otherwise exported, can be sent to the element to help heat the water.

The solar pv system quoted is estimated to generate around 6000kWh a year, which averages 16kWh a day, but obviously that will be lower in winter and higher in summer, perhaps over 40kWh on a good day (quote shows a monthly estimate chart). So a 5.2kWh battery is quite small for the solar but would act as a buffer for intermittent generation and demand during the day, and provide stored energy for the evening. Depending on consumption, that may be all the capacity needed, but it can be added to later on.

I am inclined to go ahead as advised by the contractor, but im conscious there is a lot in the quote I dont truly understand so just wanted to put this out there to unconnected parties so I can become aware if I am missing something or should be asking for something different or more clarification. 

Would welcome any thoughts / advice regarding the above. 

You could be missing out on exporting 1000kwh a year by only having a 6kw inverter.

[Deleted User]

You could be missing out on exporting 1000kwh a year by only having a 6kw inverter. 

Possibly, but often a smaller inverter is chosen to maximise output during the Winter period. The installer’s design software usually determines the optimum inverter size. 

2nd_time_buyer

Out of interest I modelled my system in the Solaredge designer software last year.

6.72 kw split over SE and SW. The peak DC output from the panels is predicted to be 6.0kw.

With the 5kw inverter that I have, the clipping loss is 0.25% and the inverter efficiency loss is 0.95%. total annual production is 6.85mwh

With a 6kw inverter, the clipping loss is 0% and the inverter efficiency loss is 1.04%. Annual production is 6.63mwh

With a 4kw inverter, the clipping loss is 2.04%, inverter efficiency loss is 0.9%. Annual production is 6.71mwh

So basically it makes surprisingly little difference but it is marginally better to have an inverter slightly undersized compared to peak DC output of the solar panels. Although, you could even argue that the 4kw inverter could be optimum for the reason that energy at low power output is more useful.