Solar panel survey visit - questions to ask.

[Deleted User]

Alnat1 said:

I'm not aware of any particular fire risks from inverters/batteries, ours are in the integral garage, many have them in the loft.

I'm aware of many - they keep me in a job.

Astria said:

I assume that people who have them in the loft would use lithium iron phosphate batteries as they don't experience thermal runaway like normal li-ion batteries and can be mishandled without adverse effects.

Safer, but not absolutely safe.  There are several ways in which a LiFePO4 can fail and cause a fire.

Alnat1

I advised our household insurance company when we had the solar/battery installed and they advised there was no change in our premium. If there was such a great fire risk, I'm sure we would be paying more?

[Deleted User]

Alnat1 said:

I advised our household insurance company when we had the solar/battery installed and they advised there was no change in our premium. If there was such a great fire risk, I'm sure we would be paying more?

Not a great risk, a particular risk.  And the insurance underwriters don't really understand that yet.  I have meetings with many of them who are completely confused by the whole thing.

Astria

[Deleted User] said:

Astria said:

I assume that people who have them in the loft would use lithium iron phosphate batteries as they don't experience thermal runaway like normal li-ion batteries and can be mishandled without adverse effects.

Safer, but not absolutely safe.  There are several ways in which a LiFePO4 can fail and cause a fire.

Could you list a few? Not doubting you just interested as that was my understanding.

PennyForThem_2

I too asked Insurance Provider - no probs as far as they are concerned.

[Deleted User]

Astria said:

[Deleted User] said:

Astria said:

I assume that people who have them in the loft would use lithium iron phosphate batteries as they don't experience thermal runaway like normal li-ion batteries and can be mishandled without adverse effects.

Safer, but not absolutely safe.  There are several ways in which a LiFePO4 can fail and cause a fire.

Could you list a few? Not doubting you just interested as that was my understanding.

Most common - internal short circuit from iron precipitation, an effect which is encouraged by poor charging/discharging conditions (both too 'deep' and uncontrolled) . There have also been manufacturing defects (including in the separator layers and at the electrodes) which have been assumed to be the cause of some other fires (the fire destroys the defect, but you can look for manufacturing errors in cells that haven't caught fire and extrapolate whether they could have been the cause).

It's also possible to produce combustible gases (particularly from overcharging) which then escape through the pressure relief system and ignite due to an external source.

LFP and NMC are still probably the safest cell types in widespread use though. 

Bod_1234

Thanks, had my visit and all my questions were answered clearly.  It was also way better than the virtual visit I had from a more expensive company with more unrealistic payback calculations.   I also feel the price is pretty competitive, and 8 week leadtime also pretty good.

This came in around 10k.  Wondering what the general feeling is around this, either price, or quality of specified components.  ROI is estimated 6 years.

Solar Panels

TIER 1 all black 400w panel

4 kW Total Solar Power

10 x 400 Watt Panels (400w Panel)

3,952 kWh per year

Inverter

Sunsynk

3.6 kW Total Inverter Rating

1 x SUNSYNK-3.6K-SG01/03LP1

Battery

Sunsynk

5.12 kWh Total Battery Storage

1 x _FIRST BATTERY L051100-A

powerful_Rogue

Bod_1234 said:

Thanks, had my visit and all my questions were answered clearly.  It was also way better than the virtual visit I had from a more expensive company with more unrealistic payback calculations.   I also feel the price is pretty competitive, and 8 week leadtime also pretty good.

This came in around 10k.  Wondering what the general feeling is around this, either price, or quality of specified components.  ROI is estimated 6 years.

Solar Panels

TIER 1 all black 400w panel

4 kW Total Solar Power

10 x 400 Watt Panels (400w Panel)

3,952 kWh per year

Inverter

Sunsynk

3.6 kW Total Inverter Rating

1 x SUNSYNK-3.6K-SG01/03LP1

Battery

Sunsynk

5.12 kWh Total Battery Storage

1 x _FIRST BATTERY L051100-A

Not really an amazing quote. What do they mean by Tier1 panels? Have they not told you the brand? What's the warranty on the panels and the inverter?

For comparison, One of the quotes I got was:

10 x 400w Sharp panels with 25 year warranty

3.3kWh Growatt battery 10 year warranty

3.6kW Growatt hybrid inverter 10 year warranty

£7,845

Getting closer in price to your quote, another was:

16 x 400w Sharp panels with 25 year warranty

6.5kWh Growatt battery 10 year warranty

6kW Growatt hybrid inverter 10 year warranty

£10,580

Have a look around at the board on this forum I linked to. You will find lots of information about various solar quotes.

Rattusnorvegicus

The battery seems undersized, you'd fill it in a couple of hours at worst. Batteries always the expensive bit.

In the off-grid system i put 30kwh. Why?

Because i assumed overnight of 12 hours of 2kw/hr , and no wind. Thats still tiny headroom.

I use a 5Kva/4kw UPS and i get 2hr 52 minutes from a 400 watt computer server....

Which is going to be interesting if we have 3hrs rolling power cuts.... I might need more juice in the form of another battery to get me to 8kw... just for my server... no idea how you power a house off 5kwh.

Companies are scared to size correctly because battery costs are horrific when considering an install.

Bod_1234

powerful_Rogue said:

Not really an amazing quote. What do they mean by Tier1 panels? Have they not told you the brand? What's the warranty on the panels and the inverter?

Warranties: 12 Year Panel Product Warranty, 25 Year Panel Performance Warranty, 10 Year Inverter Product Warranty, 10 Year Battery Product Warranty

Usually they told me they stated exact panel, however due to the current market conditions, they will only state Tier 1, which is from a well established manufacturer with efficiency in excess of 20%