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Off Grid Andy

offgridandy

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Mar 5, 2024
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Hi everyone. Just signed in today although I have read any number of threads here previously.

I have lived off grid on a mountain side in Mid Wales (UK) for nigh on 25 years. Started out with just a Lister generator. Added battery and inverter charger and then over many years my system, built and maintained by me has grown to this.

24Kwh FLa battery 24V.
Outback VFX2430 inverter charger.
6.2Kw PV panels in 4 strings all ground mounted.
Outback FM80 PV charge controllers.
3Kw wind turbine. ac coupled feeds the house first then back feeds through the Invertor to charge battery.
10KVa LPG genset .

I also have 2 banks of solar thermal tubes to provide DHW for 8 months of the year.

Our house is a large 3 bed stone barn conversion. Highly insulated with solid floors with wet UF heating. Heat from either oil boiler, wood stove with back boiler or newly installed ASHP, which operates (currently) only when genny runs. Theory is genny has to run in winter every couple of days so when it's operating only 2.5Kw is used for battery charging so another 3Kw goes to the ASHP but fuel consumption does not double so ASHP is nearly free. Heating system is controlled by a couple of temp stats and relays on a buffer tank. All heat sources can feed the tank and when T exceeds 40'C the oil boiler is shut off and the other sources heat the house via the UFH. Sometimes I have to further run electric fires to dump power , what a chore.

Net daily energy use (electric) around 12Kw. Most generated in winter from wind turbine 40Kw in one day.

The next plan is to upgrade to a 48V system which obviously will involve an upheaval. I have a near new 50Kwh ex EV battery to reuse. Car is one year old done only 1000 miles.

So I will plan to do a post on this battery useage. I see the forum has covered this topic before but I hope you guys can guide a dinasour (25 years on lead acid ) into the sunlit uplands of new tech batteries.

Andy
 
Hi Andy, sounds like you have done well over the past 25 years off grid.
I used to live near Knighton, lovely area when the weather is good to you.

May I suggest making your system simpler to operate, as you get older you will want to do less work !!
I have built our perfect home here in Florida, one of the decisions I made was to spend the extra cash on hurricane resistant windows rather than have to mount shutters before a storm. I can do shutters easy ATM but in 20 years time I don't want to mess with them.
 
Hi Andy, sounds like you have done well over the past 25 years off grid.
I used to live near Knighton, lovely area when the weather is good to you.

May I suggest making your system simpler to operate, as you get older you will want to do less work !!
I have built our perfect home here in Florida, one of the decisions I made was to spend the extra cash on hurricane resistant windows rather than have to mount shutters before a storm. I can do shutters easy ATM but in 20 years time I don't want to mess with them.
Hi Q, I know Knighton as you say a lovely area.

My aim is always to keep things simple. I also make my plans on the basis of the following guide points.
Sh*t happens so plan for it. Keep spares in stock, you will need them.
I have a spare inverter in stock on the wall and wired into a fused breaker, if my Outback fails I simply have to switch in the back up.
No one will turn out to help if you are off grid so understand how the kit works.
Document the system so the senior partner ( wife of 40 yrs) can refeer to The Book and follow instructions . Ie manually start gen set if required.
IE my heating system will operate with any of the energy sources, failure of one element does not kill the whole system.
Last point Sh*t happens. Assume something will fail.
 
Welcome Andy! Sounds like you have it figured out. What is your weather like there? Lots of sun or very "seasonal"?
Post some pictures, We all love seeing long term off grid setups!
Also the stone barn conversion has me curious
 
Welcome Andy! Sounds like you have it figured out. What is your weather like there? Lots of sun or very "seasonal"?
Post some pictures, We all love seeing long term off grid setups!
Also the stone barn conversion has me curious
Weather is seasonal. Today is bright and sunny no wind. PV had charged the battery by 12 Noon, having pushed about 12K into the system and all CC shut down to float.
I love being off grid although 25 yrs back the plan was to have 220v mains in but I had to get a wayleave from a local land owner and he tried to hold me to ransom, wanting thousands ££ bfor the right to access. I called his bluff and spent the money on the first battery and inverter.

I get visitors who say " if you are off grid, how come you have a dishwasher, a automatic washing machine 3 freezers etc. To which I reply I may not have passed any exams etc but I am very good at running a power system. When I started I spent about £2000 on red diesel in the first year, last year my running costs for the back up gen set was £400. Cheap as chips.
 
Any streams running through your land? Hydro is also a possibility for power, and makes a seasonal complement to solar.

These are a fun watch, if nothing else: YooToob
 
You’re living the dream Andy! I hear you want to move to 48v but have you thought of going higher? Those ev batteries can make a much more efficient high voltage pack and that’s may be where the industry is headed. Check what this guy did with his project!
 
No, no streams available or I'd be all over hydro. Thanks for the video link Ben. I will study. I am not commited to any specific upgrade course yet as I have only just obtained the battery. Iwill be posting shortly my ask for help and advice with an outline of my intent and you guys can advise how to get there. Battery I've obtained is 50Kwh at 400V 108s2p.

Hope the mods don't mind. I've a utube drone footage which shows my place although I see the final cut has deleted the ground mount pv.

I'll dig out some other graphics later.
 
PV all ground mounted, no concrete used in this. Posts are set in the ground using steel "metposts" Main timber used is sold as 150mmX 35mm trreated timber for decking, very good straight grain stuff. !st PV panels went un in about 2009. So it works. I've recorded wind at 80 mph here so we do get weather and panels have never moved.
 

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I would have thought you could work out a way to harness all the rain energy you get in Wales....😁😁
Seriously, great post and looking forward to your next project. There's been a few used car batteries on eBay recently from a UK seller, they might be prepared to share 'notes'??

Good luck with the project
 
No, no streams available or I'd be all over hydro. Thanks for the video link Ben. I will study. I am not commited to any specific upgrade course yet as I have only just obtained the battery. Iwill be posting shortly my ask for help and advice with an outline of my intent and you guys can advise how to get there. Battery I've obtained is 50Kwh at 400V 108s2p.

Hope the mods don't mind. I've a utube drone footage which shows my place although I see the final cut has deleted the ground mount pv.

I'll dig out some other graphics later.
Welcome Andy, that's a sweet little location you got there Andy...
 
Hi Andy,
I have similar kit bar except the wind and only 14 years on 24V, is the availability of the battery the only driver to 48V?
 
Hi Andy,
I have similar kit bar except the wind and only 14 years on 24V, is the availability of the battery the only driver to 48V?
Well sorry I missed this, Power demand has grown here over the years along with greater generating ability. A 48 V system perhaps with 2 inverter chargers in parallel will enable me to have higher demand when needed. Eg if we have the washing machine on and then put on the coffee machine, on 24V that would automatically start the genny even if the WT is running. On 48 V I will be able to absorb, short term higher loads with out the generator starting. The change to 48V system will also result in a larger battery size overall so my days of power storge in the battery are greater as well.
 
Well sorry I missed this, Power demand has grown here over the years along with greater generating ability. A 48 V system perhaps with 2 inverter chargers in parallel will enable me to have higher demand when needed. Eg if we have the washing machine on and then put on the coffee machine, on 24V that would automatically start the genny even if the WT is running. On 48 V I will be able to absorb, short term higher loads with out the generator starting. The change to 48V system will also result in a larger battery size overall so my days of power storge in the battery are greater as well.
when i built my cabin system I went straight to 48 volt system. my camper was a 12 volt system

While designing the cabins power system I initially considered just stripping out the campers system and enlarging the battery bank, but after thinking about it a bit I decided in the future I would need more power so i started looking at the 24 and 48 volt offerings. as I was building from scratch the decision was easier for me. smaller cabling, or better yet the same size cabling for less voltage drop.

since you already have a 24 volt system jumping up to a 48 volt inverter you should be able to use almost e very bit of battery cable etc. that you have. so no loss there. what vehicle did the battery pack come from?
 
The new battery that I'm boing to have to repurpose, as it is currently all wired in series to give 400VDC is from a Peugeot Boxer van 2022 plate with only 1000 recorded miles.


The battery as built for Peugeot is as follows.

51 KWh.

Pack voltage 400V

Capacity 127.5Ah.

Total cells 216

Battery pack 108s2p



I've stripped this down to individual modules 18 off, all at 22 v. I plan to recombine the modules, 2 in series to give me 44V nominal. I will therefore have 9 pairs of modules in parallel onto the busbar.. 50Kwh total battery storage. Each module has an on board pcb which does the BMS stuff and also cell pack temp.

I am currently looking for assistance to read the chip set and work out how to utilise the data.
 
The new battery that I'm boing to have to repurpose, as it is currently all wired in series to give 400VDC is from a Peugeot Boxer van 2022 plate with only 1000 recorded miles.


The battery as built for Peugeot is as follows.

51 KWh.

Pack voltage 400V

Capacity 127.5Ah.

Total cells 216

Battery pack 108s2p



I've stripped this down to individual modules 18 off, all at 22 v. I plan to recombine the modules, 2 in series to give me 44V nominal. I will therefore have 9 pairs of modules in parallel onto the busbar.. 50Kwh total battery storage. Each module has an on board pcb which does the BMS stuff and also cell pack temp.

I am currently looking for assistance to read the chip set and work out how to utilise the data.
Wow, way above my skill set. best of luck and following just to learn a bit. Expect stupid Questions... I am a Crayon Eater by Trade and really good at amphibious assault not much else though.
 
So I will plan to do a post on this battery useage. I see the forum has covered this topic before but I hope you guys can guide a dinasour (25 years on lead acid ) into the sunlit uplands of new tech batteries.

Andy
It appears that you are positioned to guide many of us! The battery project looks like it will keep you running for many years.

I transitioned from 24v FLA to 48v LFP batteries a few years ago. It was an upheaval: new inverters, battery relocation to inside the house, lots of rewiring, etc. The elimination of long absorption and equalization charges was a tremendous benefit, esp. in winter when the generator is relied upon. Another benefit is that I used the 24v Outback gear to upgrade a cabin from its 12v Xantrex/Trace gear.

Have fun!
 

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