ok I''m over here 'exploring on my bike' lol

let's say I wanted to live 'off grid' with my collection of bikes including an ebike or 2....

if I got say 2 x 340w* panels, what sort of battery setup would i need to power an aircon unit and small fridge overnight? And a recommended MPPT controller?

I recall i think it was @Crossy bought some amazingly cheap LifePO4 batteries from somewhere online a while ago, still deals available?

thanks!

*I know that's not a lot, I'm a minimalist nowadays lol

19 minutes ago, driver52 said:

f I got say 2 x 340w* panels, what sort of battery setup would i need to power an aircon unit and small fridge overnight?

First of all 2 panels is not a lot. 

 

what is the BTU of your aircon? And is it an inverter? How long does it need to run of batteries?

what is the usage of your fridge during the night? (Now is a good time to test as tge fridge is working very hard because of the heat)

 

Maybe buy a power monitor to check the usage of the fridge and then you can start to estimate your battery setup.

 

Wont you run anything else of these batteries? Lights etc etc

Edited April 25, 20233 yr by MJCM

6 minutes ago, MJCM said:

First of all 2 panels is not a lot. 

 

what is the BTU of your aircon? And is it an inverter?

what is the usage of your fridge during the night?

 

Maybe buy a power monitor to check the usage of the fridge and then you can start to estimate your battery setup.

 

Wont you run anything else of these batteries? Lights etc etc

hi, thanks for input......as I'm 'exploring' I'm just between places on airbnb and agoda at the moment so haven't even decided on a 'semi-permanent' place even

i'm just thinking 'small place', small aircon, small fridge (i'm doing OMAD, cycle every day and generally live off Thai street food)........lights are a non-issue to me, as the circa 8watt bulbs don't take any power and I can buy LEDs....and I don't even like hot showers anymore!!!

cheers!

@MJCM has it right, the "correct" way to do this is number one do an energy audit.

 

To start you off.

A 9000BTU A/C (say 15m² room) will run to 900W at full chat, if it's correctly sized for the room expect it to use about 0.3kWh per hour. Say 10 hours per day = 3kWh, that's already around 3 panel's worth.

Of course, if you want to run at night then you're looking at that much storage. At 12V that's 250Ah of usable storage (so 500Ah of lead-acid).

 

Give us an idea of just what you expect to be running and we can come up with some sensible suggestions.

 

Do you want to be truly off-grid or will there be grid backup available for those dull days?

 

 

 

14 minutes ago, Crossy said:

 

Give us an idea of just what you expect to be running and we can come up with some sensible suggestions.

 

Do you want to be truly off-grid or will there be grid backup available for those dull days?

actually I've just had a 'recollection' lol.......I remember those 'DIY aircon' using a 'foam box' full of ice and a hole in the top with a fan......

i know I'm sounding like a tramp but I haven't even found anywhere to live yet........I'm really interested in living a simple off-grid life....

I just bumped into a guy on a bike ride this morning and he was convincing me I don't need a car........just look at those 9-10baht bags of ice you can buy too.....cheaper in bulk surely? I've seen guys delivering them on motorbikes!!! ????

Edited April 25, 20233 yr by driver52

OK, a splash of reality.

 

A 12,000 BTU A/C is known as "one ton" in some parts of the world because it produces the same cooling effect (if running at 100% duty cycle) as melting 1 ton of ice over 24 hours.

 

Our 9,000 BTU unit would be 0.75 tons which would (using our 30% duty cycle) need 250kg of ice every 24 hours!

 

The melting-ice coolers do work, but in reality, they only produce a stream of cooled air for a relatively short time.

14 hours ago, Crossy said:

The melting-ice coolers do work, but in reality, they only produce a stream of cooled air for a relatively short time.

ok, I did a test overnight and slept without the aircon from 11pm, it was fine

I'll post this here for future reference, I came across the inspiration for this project a few years ago and actually have a never used DPS5020 but it's in a different country

https://gitlab.com/larsfp/esphome-mppt

2 hours ago, driver52 said:

ok, I did a test overnight and slept without the aircon from 11pm, it was fine

Please note, I recall you say that you don’t have your own place yet, so You can’t compare your current situation with the future.

 

There are a lot of factors to look out for

 

- insulation of the room / house

- how big is the room

- does the room gets sunshine during the day or only in the afternoon 

- is it well shaded

etc etc.

 

example: our old house is much better insulated then our current house, one fan would be good enough for the whole living room, but our current house (build on the quick) needs at least 2-3 fans. Same for the bedroom as the bedroom gets much more shade the aircon doesn’t have to work that hard.

 

So do that test again when living in your definite place (and same temperatures preferably ???? )

Edited April 26, 20233 yr by MJCM

can somewhere please tell me what those 3 things are on top left board? I can see a 'solar isolator' what do the Thais call it? can't find it on lazada

and those other 2 things, a fuse and ? cheers

 

The brown thing top left is a Chang knife switch which looks like it's being used as a solar isolator, top right looks like an AC rated MCB, the + - markings confuse me somewhat but I suspect it's being used to connect to the mains.

 

Bottom device looks like an energy meter to check your production.

 

I also note a Schuko type plug rammed into a Thai outlet, so no earth continuity which with a transformerless inverter like that one could lead to a shock hazard from the panel connections.

 

  

On 4/25/2023 at 3:45 PM, driver52 said:

if I got say 2 x 340w* panels, what sort of battery setup would i need to power an aircon unit

12kWhr battery will power a 9kbtu air-con for 10hrs.

That battery would cost around 52,000bht.

28 minutes ago, driver52 said:

can somewhere please tell me what those 3 things are on top left board? I can see a 'solar isolator' what do the Thais call it? can't find it on lazada

and those other 2 things, a fuse and ? cheers

 

Apart from the Suoer 1000w GTI, nothing else in that photo is required.

The Suoer plugs direct into any mains socket (I have that unit).

If you have a problem, you can switch it off, or pull the plug out.

 

I had 3x 340W panels connected to mine in parallel (max panel voltage 45V).

If you plug the panels in series, it will smoke and fail.

24 minutes ago, BritManToo said:

 

I had 3x 340W panels connected to mine in parallel (max panel voltage 45V)

ok interesting cheers, you say 'had', have you got a different system now?

13 minutes ago, driver52 said:

ok interesting cheers, you say 'had', have you got a different system now?

I previously had

1kW suoer + 3x 340 panels

600W suoer + 2x 340 panels

 

Which I upgraded to 5.5kW hybrid + 9x 340W panels + 6kWhr battery. 

 

Cos I got fed up with power cuts whenever it got wet or windy. 

13 minutes ago, BritManToo said:

6kWhr battery

which batteries did you go for and what cost?

44 minutes ago, driver52 said:

which batteries did you go for and what cost?

I did CALB s/h batteries which were a mistake. If I could choose again I'd get nmc 280x14 for around 50kbht.

1 hour ago, BritManToo said:

I did CALB s/h batteries which were a mistake. If I could choose again I'd get nmc 280x14 for around 50kbht.

i think batteries are a bit of a 'mine field' in more ways than one......a guy I know in frogland nearly burnt his house down charging his remote control plane and helicopter batteries in the living room.....

i love technology but not sure I'd have a leccy car just yet, leccy bike bring it on ????

Edited April 27, 20233 yr by driver52

On 4/27/2023 at 4:37 PM, BritManToo said:

I had 3x 340W panels connected to mine in parallel (max panel voltage 45V).

What gti model do you recommend.  Been looking on Lazada, & can't find 1000W  model that goes up to 45V.  

11 hours ago, Yorkshire Tea said:

What gti model do you recommend.  Been looking on Lazada, & can't find 1000W  model that goes up to 45V.  

This is the one I have (but with a Suoer label on it).

https://www.lazada.co.th/products/grid-tie-inverter-scl-fti-d1000b-1000vafti-d600b-600va-monitor-pure-sine-i2481341480-s8742948948.html

7 hours ago, BritManToo said:

This is the one I have (but with a Suoer label on it).

https://www.lazada.co.th/products/grid-tie-inverter-scl-fti-d1000b-1000vafti-d600b-600va-monitor-pure-sine-i2481341480-s8742948948.html

Have you seen any that can handle 1200 - 1500W?   I'd like to connect 4 solar panels.

On 5/8/2023 at 1:51 PM, Yorkshire Tea said:

Have you seen any that can handle 1200 - 1500W?   I'd like to connect 4 solar panels.

carefully with these....on Aliexpress they are. I have a 1200 and a 1300W and they are inside identically with the 1000 Watt, even on the board is printed 1000W. It is possible that they put in the next stronger MosFets...but I doubt it. I complained at Aliexpress and got a $25 back from the cost of $100-150

2 hours ago, h90 said:

carefully with these....on Aliexpress they are. I have a 1200 and a 1300W and they are inside identically with the 1000 Watt, even on the board is printed 1000W. It is possible that they put in the next stronger MosFets...but I doubt it. I complained at Aliexpress and got a $25 back from the cost of $100-150

Found on Lazada.

 

https://www.lazada.co.th//products/i2238394281-s7485735803.html?spm=a2o4m.cart.0.0.5fe36108E2AhOO&urlFlag=true