Next Storm

[Joeboy]

Up early today and heard on radio this morning that storm Barra arrives tomorrow. This led me to consider power failure at the house. Sadly, my system is grid tied so if the grid goes off so does the system. This led me along a simple mental path to T,ing in a 48Vdc to 220Vac inverter off the battery stack for grid fail use direct from the battery stack. Could rotary isolate until actually needed? Hopefully once in a Blue moon. Thoughts?

[Joeboy]

Would also have the second array continuing to output independently of the grid and into the batteries. That's actually a bit of a no brainer upgrade to the overall system.

Storm knocks power out, fallback is a hopefully full 14.4kWh battery stack running low energy lighting off of extension reels via an inverter and daycharging stack at whatever meager Winter solar inflow there is.

Lights are on and Woodstove is heating and cooking.

[Joeboy]

That's 65 hours from 100% to 10% soc.at 200Wh of lighting. Four days at 16 hours per day with no incoming from PV. I'm having that!

[Joeboy]

https://www.amazon.co.uk/Xijia-1500W-In ... =8-10&th=1

Thoughts?

[Stinsy]

I've given this a LOT of thought over the last few weeks!

Here is my "plan" in the event of a multi-day outage:

• Disconnect house from grid via DNO's DP isolator.

• Switch off All breakers in CU.

• Go round the house unplugging/turning off anything non-essential.

• At Inverter move mains cable from "Grid" to "UPS".

• Turn on all breakers in CU except "Hob" and "Ovens".

In summer that'd be it. Job done. I'd have more power than I could use.

But... Since when did multi-day outages occur in summer?

So I'd have to purchase / hire a generator and run a cable from the generator to the "grid" connection of my inverter and set the charge-rate to something sensible. Obviously I'd have to take what I could get but something like this: https://www.machinemart.co.uk/p/clarke- ... generator/ should do the job. I imagine filling it up with fuel in the morning setting it running until the fuel ran out then lasting on batteries until the next day.

The critical parts are: not knowing how long the outage will last. If you know it's going to be 5-10 days, buying a genny is a no-brainer. But if the power is coming back on tomorrow it doesn't seem worth the hassle/money. I'm also not prepared to buy a genny "in case", because it'll probably never happen, so will have to move fast before generators are sold out everywhere.

[Stinsy]

https://www.amazon.co.uk/Xijia-1500W-In ... =8-10&th=1

Thoughts?

Not cheap enough for unknown quality/reliability.

For that money you might as well buy one of these: https://www.bimblesolar.com/offgrid/inv ... &order=ASC

[spread-tee]

I guess it depends how often you have power cuts? as an add-on to the kit you already have it is a small job and outlay. I did consider a similar kind of add-on using just a leisure battery to keep the solar thermal pump running when we had a cut during very bright sunny weather, with 60 tubes on the roof it was exciting to say the least. Needless to say the round tuit has not been found yet

Desp

[Joeboy]

Storm Arwen has been a cracking catalyst for me. I had half the solution already in place (The 4kW+ second PV system and PV powered Victron charge controller). I lose one system due to power outage, that's ok though (cheers Nowty! look how far this is now going). I was lacking the 240Vac conversion. Admittedly I have went short money, single power line route rather than a more complicated switch over of entire home. The inverter can take a 4kW surge and consistently run at 2kW load. That's the fridge freezers, comms and washing machine covered although I'd leave that last unless it was a Summertime failure. Obviously I'll be running as many extension reels off that one inverter socket as possible (joke).

Happy to spend a couple of hundred quid to make us slightly more bombproof. I might have got here myself but TBH storm Arwen has been a strong driver.

[Joeboy]

https://www.amazon.co.uk/Xijia-1500W-In ... =8-10&th=1

Thoughts?

Not cheap enough for unknown quality/reliability.

For that money you might as well buy one of these: https://www.bimblesolar.com/offgrid/inv ... &order=ASC

Cheers Stinsy, would have been nice to add to my Victron collection. Sadly the rabbits away already. I've been running a similar Chinese inverter on the Bongo 12V-240V/800W for a couple of years and it has been excellent. I look forward to installing and simulating grid failure.
Also glad that the inverter has LCD gauges to show power remaining in Stack. Not sure if Pylontechs have any internal mointoring to stop me pulling the stack below 10% SOC but at least i'll know when i'm getting close on the LCD display.

[Joeboy]

I guess it depends how often you have power cuts? as an add-on to the kit you already have it is a small job and outlay. I did consider a similar kind of add-on using just a leisure battery to keep the solar thermal pump running when we had a cut during very bright sunny weather, with 60 tubes on the roof it was exciting to say the least. Needless to say the round tuit has not been found yet

Desp

To be completely transparent, we were close to losing the village where our other hoose is in Turkey due to the fires back in August. Largely blamed on climate change across the Eastern Med this year. Laterally I personally have never seen so many trees down and damage as caused by Arwen. Another sign of climate change? Probably not, its gotta blow a hooly sometime and it sure has. I am now 52 and both myself & SWMBO are ongoing seduced by a kind of bunker mentality with regard to self sufficiency. Power outages at our place here in Scotland? very rare. Yet on that day, imagine how i'd feel! Powers out, multiple thousands of gear, a load of stored energy and dobber here can't access it... No thank you!

As you say 'it's an add on' and I can almost see it as a logical conclusion to a two year process of the second PV system install. I have thought about a LPG powered genset but in our case with the Woodstove it really comes down to lights & comms only. Hell, I can user the WS heated kettle for a sluice down (nasty image).

Desp,
With that amount of solar thermal for the HW what is the fallback solution, can you attach a cold water hose and break into or install a T piece manual op valve to purge the HW? Would it eventually blow the system if let uncirculated? I know nothing of solar thermal so interested to learn?