The start of my new 'Off grid' Solar install.

[Crossy]

10 minutes ago, SomchaiDIY said:

mr roland has the large second hand lifepo4 pack where pack has custom charge state monitor and setting to avoid stress of used cell pack

 

Yeah, those look like the 100Ah green Sinopoly cells that are flooding the market at present.

 

Probably the cheapest way in to LiFePO4 ???? 

 

[Muhendis]

From reading some of the recent comments regarding BMS and chargers, please note the following:

 

1) The battery charger will charge a battery up to a pre-selected level. It is this which determines the maximum state of charge of the battery. It will also begin the charging process if the battery voltage gets to the minimum voltage setting of the charger.

 

2) The BMS is a switch (if you like) which will disconnect the battery if the charger tries to exceed the maximum safe voltage of the battery.

It will also disconnect the battery if, during discharge, the battery voltage gets to the minimum safe voltage of the battery.

 

Both of the above can be caused by some cells being better/worse than others. The BMS will try to balance all the cells by transferring charge from the better charged cells to the lesser charged cells. Apart from this the level of charge is not controlled by the BMS but by the charger.

[Pink7]

Here is a estimate i got from a recommended trusted seller in China some weeks ago: 

 

---

For 16 cells EVE LF280K, the total is 16*110+458.7USD=2218.7USD, add 2.5% Alibaba fee. 

For 32 cells, the total is 32*110+896.7USD=4416.7USD, add 2.5% alibaba fee. 

---

The cost of the batteries more or less as expected , but the shipping cost is to cry off..

 

 

Pink

 

 

[SomchaiDIY]

7 hours ago, Muhendis said:

From reading some of the recent comments regarding BMS and chargers, please note the following:

 

1) The battery charger will charge a battery up to a pre-selected level. It is this which determines the maximum state of charge of the battery. It will also begin the charging process if the battery voltage gets to the minimum voltage setting of the charger.

 

2) The BMS is a switch (if you like) which will disconnect the battery if the charger tries to exceed the maximum safe voltage of the battery.

It will also disconnect the battery if, during discharge, the battery voltage gets to the minimum safe voltage of the battery.

 

Both of the above can be caused by some cells being better/worse than others. The BMS will try to balance all the cells by transferring charge from the better charged cells to the lesser charged cells. Apart from this the level of charge is not controlled by the BMS but by the charger.

The charger for most system is master of charge voltage but this story is going more to complex directions

 

It is truth for most system the bms is the safety cut not charge control

 

There many type of bms balance but most are use the bypass dump method

 

Share of data between parts is slowly more popular 

 

Big advantage for all system part to know all data example main circuit shunt

 

Some bms can take charge state then look to all cell levels to make choice how / when to set balance logic

 

High current bms dump can calculate energy dump when on balance and send result to charge state calculation

 

Technologies for this story is fast moving
 

[BritManToo]

14 hours ago, Pink7 said:

Here is a estimate i got from a recommended trusted seller in China some weeks ago: 

 

---

For 16 cells EVE LF280K, the total is 16*110+458.7USD=2218.7USD, add 2.5% Alibaba fee. 

For 32 cells, the total is 32*110+896.7USD=4416.7USD, add 2.5% alibaba fee. 

---

The cost of the batteries more or less as expected , but the shipping cost is to cry off..

Pink

Found a Thai seller with brand new and boxed BCT rack units 48V x 200AH for 52kbht.

https://www.facebook.com/solarshopsangfahnonthaburi

[KhunLA]

16 minutes ago, BritManToo said:

Found a Thai seller with brand new and boxed BCT rack units 48V x 200AH for 52kbht.

https://www.facebook.com/solarshopsangfahnonthaburi

'solarshop' ... I think that's who my installer will be dealing with, as there's a local branch at Hua Hin.

I priced components I would need, and it isn't worth me doing the installation vs the installer's price.

[BritManToo]

First complete month of my mainly 'off grid' install

 

And my total PEA bill is ........... 48units, 208bht. (for hot showers, air-con and a bit of evening cooking)

Before solar this months bill would have been 1,500bht.

[AP2019]

Wow. A great achievement.  Do you have a business for this? If so, what province are you in?

 

What if you didn't want to use batteries, does Thailand allow solar to work during power outages (would only be good for daylight hours).

 

Regards

-a

[Eff1n2ret]

22 hours ago, AP2019 said:

What if you didn't want to use batteries, does Thailand allow solar to work during power outages (would only be good for daylight hours).

Not if you're hooked up to the grid - they don't want to risk their electricians working on power lines that might be live. It's very irritating to have no power in the house when your panels could be supplying it.

[BritManToo]

51 minutes ago, Eff1n2ret said:

Not if you're hooked up to the grid - they don't want to risk their electricians working on power lines that might be live. It's very irritating to have no power in the house when your panels could be supplying it.

45 min power cut 9pm last night after the wind/rain/lightning, seemed to be all of MaeJo ...... apart from me.

I was the only house in the MooBaan with full electricity.

[Hummin]

Can you get decent household plug and play complete packages with battery lasting all night running two aircons 12 500 and 19 000 btu? 
 

Price for complete package ? 

[Crossy]

1 hour ago, Hummin said:

Can you get decent household plug and play complete packages with battery lasting all night running two aircons 12 500 and 19 000 btu? 
 

Price for complete package ? 

 

The batteries are going to be the killer, the A/C will swallow about 1.2 units per hour if they are correctly sized and you don't keep polar bears. So say 14.4kWh per night.

 

Say about 300Ah at 48V of LiFePO4 (double that for lead-acid).

 

Do you have grid power for backup on dull days?

 

Note, that's just for the A/C!

 

Do you want to DIY install or use a contractor?

 

[Hummin]

27 minutes ago, Crossy said:

 

The batteries are going to be the killer, the A/C will swallow about 1.2 units per hour if they are correctly sized and you don't keep polar bears. So say 14.4kWh per night.

 

Say about 300Ah at 48V of LiFePO4 (double that for lead-acid).

 

Do you have grid power for backup on dull days?

 

Note, that's just for the A/C!

 

Do you want to DIY install or use a contractor?

 

Thanks, we are on grid but almost pay 8 baht pr unit since we are 350m from the last fixed pole, and have 30 amp box. 
 

My plan is in two years have the perfect set up for us, with legal switch for connecting to the grid. 
 

A simular to the Tesla powerwall I had in mind. 

[Crossy]

14 minutes ago, Hummin said:

Thanks, we are on grid but almost pay 8 baht pr unit since we are 350m from the last fixed pole, and have 30 amp box. 

 

Are you still on a "construction" supply at that rate??

Billed direct from PEA?

[Hummin]

2 minutes ago, Crossy said:

 

Are you still on a "construction" supply at that rate??

Billed direct from PEA?

Yes, I can't change it!

[Crossy]

Just now, Hummin said:

Yes, I can't change it!

 

There has to be a solution (we are in Thailand, there's always a solution), what are the reasons you're stuck on cuch a rate?

[BritManToo]

2 hours ago, Hummin said:

Can you get decent household plug and play complete packages with battery lasting all night running two aircons 12 500 and 19 000 btu? 

I'd suggest you learn to live without air conditioning.

Becoming acclimatised to the country gives you a much better living experience.

You sweat less and are much more comfortable outside.

[Hummin]

4 minutes ago, BritManToo said:

I'd suggest you learn to live without air conditioning.

Becoming acclimatised to the country gives you a much better living experience.

You sweat less and are much more comfortable outside.

I doubt I will, and I can pay 5k or 10k a month, it will not change my habits sleeping with aircon. Two aircon running is only when we have visitors, and our bill now is 2 800,- a month depending on how often we circulate the fish pond. Will change that pump to solar when coming back. 
 

@Crossy

 

They say the rule is 20m from meeter (last electric company pole) to house, everything further away double price. 
 

we talked to village boss, since there is not only us, and she said she will take care of it. Now 8 months later we have no answer. 
 

Thais have patience at least my family, and also have not guts to say what they mean to officials, and we have to use the correct line of power, the Village boss. 
 

Same the National park service was to come and give us the correct sticks border agains their land, but somebody whispered in to my ear, they will not come before someone hand over 10k.

 

Our neighbour farmer is constantly cutting trees on national park, and we fear, we will be included in his problem when they come for him. But thats another topic.  

[Crossy]

1 hour ago, Hummin said:

They say the rule is 20m from meeter (last electric company pole) to house, everything further away double price.

 

We are 60m from pole/meter to house, 4.x Baht per unit!

 

Where is your meter on the last PEA pole or somewhere else?

 

I'm sure someone is playing games and looking for a little "lubrication", like I said, there's always a solution, could be solution of ethanol in water labelled "Johnny Walker"

 

EDIT It's possible they are saying that you wouldn't pass the inspection for a permanent supply due to distance, but with the correct cable that too should be fixable.

[Hummin]

34 minutes ago, Crossy said:

 

We are 60m from pole/meter to house, 4.x Baht per unit!

 

Where is your meter on the last PEA pole or somewhere else?

 

I'm sure someone is playing games and looking for a little "lubrication", like I said, there's always a solution, could be solution of ethanol in water labelled "Johnny Walker"

 

EDIT It's possible they are saying that you wouldn't pass the inspection for a permanent supply due to distance, but with the correct cable that too should be fixable.

Everything is in spec due to standard norm, but thanks, will work on it 

[BritManToo]

Update:

In the middle of CM pollution my 9x 330W panels maxed out at 1.7kW.

Now we're in monsoon and the air is clear my 9x 330W panels max at 2.6kW.

 

pollution Vs monsoon ...........

 

 

 

That's a 30% loss of sunlight due to air pollution. 

Due to the monsoon clouds, I actually end up producing the same amount of electricity.

Amazing Thailand.

[sezze]

On 4/27/2022 at 10:25 AM, Hummin said:

I doubt I will, and I can pay 5k or 10k a month, it will not change my habits sleeping with aircon. Two aircon running is only when we have visitors, and our bill now is 2 800,- a month depending on how often we circulate the fish pond. Will change that pump to solar when coming back. 
 

@Crossy

 

They say the rule is 20m from meeter (last electric company pole) to house, everything further away double price. 
 

we talked to village boss, since there is not only us, and she said she will take care of it. Now 8 months later we have no answer. 
 

Thais have patience at least my family, and also have not guts to say what they mean to officials, and we have to use the correct line of power, the Village boss. 
 

Same the National park service was to come and give us the correct sticks border agains their land, but somebody whispered in to my ear, they will not come before someone hand over 10k.

 

Our neighbour farmer is constantly cutting trees on national park, and we fear, we will be included in his problem when they come for him. But thats another topic.  

Well if your electric bill is 2800 baht for a 8 baht rate , then it is very possible . That's 350 units a month or +/-12 kWh per day . It also means you aren't running all the aircons , prob just 1 in the bedraom . To offset that amount you need to get around 4 kW of solar power , a 5000W (are your aircons inverters , very important for the startloads!)  hybrid inverter , and 10 kW battery ( for those inverters it would mean 48V 200 Ah ) . Now this is a minimum , but it will cover a 350kWh load ( most of the time) . Adding more batteries will always be beneficial , since doubling on those would create a large buffer , for less sunny days , and or keep your batteries just last much longer .

You can think about it is all gonna cost , depending on your provider of all items .

solar panels now , most are 1.2 baht per watt ( there still are a few cheaper around ) , so 4kW sets you back 50000k

inverter between 15000 and 50000 all your choice

batteries , 10 kW , 50k with a bit of looking around

the rest are bits and pieces , like mounting rails , switch box , wires ... just make that a easy 10k .

 

Do not forget your peakload , idk you installation and what you do , but if you got a like a 4500 watt water heater , or a swimming pool pump of 3hp , then the inverter just won't cut it . Then its over to the design table .

[Hummin]

9 minutes ago, sezze said:

Well if your electric bill is 2800 baht for a 8 baht rate , then it is very possible . That's 350 units a month or +/-12 kWh per day . It also means you aren't running all the aircons , prob just 1 in the bedraom . To offset that amount you need to get around 4 kW of solar power , a 5000W (are your aircons inverters , very important for the startloads!)  hybrid inverter , and 10 kW battery ( for those inverters it would mean 48V 200 Ah ) . Now this is a minimum , but it will cover a 350kWh load ( most of the time) . Adding more batteries will always be beneficial , since doubling on those would create a large buffer , for less sunny days , and or keep your batteries just last much longer .

You can think about it is all gonna cost , depending on your provider of all items .

solar panels now , most are 1.2 baht per watt ( there still are a few cheaper around ) , so 4kW sets you back 50000k

inverter between 15000 and 50000 all your choice

batteries , 10 kW , 50k with a bit of looking around

the rest are bits and pieces , like mounting rails , switch box , wires ... just make that a easy 10k .

 

Do not forget your peakload , idk you installation and what you do , but if you got a like a 4500 watt water heater , or a swimming pool pump of 3hp , then the inverter just won't cut it . Then its over to the design table .

You are right, we only run one aircon 12000 btu inverter about 12 hours at most, and daytime I got one 1900 without inverter going for a few hours in my gym. But we have two more aircons when we have guests, but then we will run on the grid. We also have 3 freedges, and one box freezer, and circulation pump in pond 1,8 m3 a minute, 2500w if not mistaken. 
 

How does the shutter system work, when the grid goes down? Is that legal? 

[sezze]

Freezers are nothing , they are large consumers in any household , but that is because of the 24h/7 consumption . On hourly basis , it's a ok load . The circulation pump if it is correct , that might be a problem . Is that running all the time ( can't be since that alone would be way over your 350 kWh use / month ) ? You need to check it , is it a start stop with timer ? Also , a 2500watt pump is not small , can be but it certainly would be a problem . Startloads on such things are big and most solar inverters do not like it . There are ways around it , like the low frequency inverters which are better suited for it , but otherwise you better check in front . You could also run it like the additional aircons on different grid ( aka your incoming lines split between your normal household and then the other ones who only run on the grid ) . Sounds complicated but really it isnt , since you need fusebox for you solar inverter anyway , 1 is powered by the inverter the other one direct from grid .

Also Your aircon in gym , i guess you mean a 9000btu unit , non inverter type . Thats ok for a 5000 watt inverter . 9000 btu is 750 watt engine , so peakload is still well under the 2hp ( 1500watt) which in general is the max a 5000 watt inverter can handle .

[BritManToo]

Last months PEA bill 57 units, 250bht (previous month 48 units).

The monsoon, 4 days of continuous rain added the extra 9 units as my batteries ran out

[Pink7]

BritManToo how is the experience with your Powmr after some months usage? 

 

Pink

[Pink7]

On 5/21/2022 at 8:47 PM, sezze said:

Do not forget your peakload , idk you installation and what you do , but if you got a like a 4500 watt water heater , or a swimming pool pump of 3hp , then the inverter just won't cut it . Then its over to the design table .

Thanks for that info.. I have 2 x 4500 watt showers. I forgot this when calculate my watt usage. So this kill the all in one options?

 

Pink

[Crossy]

1 hour ago, Pink7 said:

Thanks for that info.. I have 2 x 4500 watt showers. I forgot this when calculate my watt usage. So this kill the all in one options?

 

Pink

 

Not really, if you have grid power just arrange the wiring to supply the heaters from the grid.

 

Otherwise add inverters, the Growatt 5kW units will surge to 10kW so a couple of those in parallel would do the trick, you may also want to add a shower priority switch, whichever heater goes on first gets the supply, the other has to wait until number one is finished. 

[Pink7]

44 minutes ago, Crossy said:

Good ideas.. My heaters have breakers outside the bathrooms , i dont know if i dare to hope they have separate wire all the way to main supply.

 

44 minutes ago, Crossy said:

Not really, if you have grid power just arrange the wiring to supply the heaters from the grid.

 

Otherwise add inverters, the Growatt 5kW units will surge to 10kW so a couple of those in parallel would do the trick, you may also want to add a shower priority switch, whichever heater goes on first gets the supply, the other has to wait until number one is finished. 

 

[BritManToo]

21 hours ago, Pink7 said:

BritManToo how is the experience with your Powmr after some months usage? 

 

Pink

It's only gone mad once.

Daughter was using an electric iron late at night, power went off, inverter screamed with red lights.

Fault 05 = op short or internal overheat. Not sure why it would overheat using 1,600W at night, but lots of extensions used as well so could have been a short. Turned everything off, turned everything on and all working again. Now banned from using the iron after dark, mainly 'cos I don't want to fiddle around in the dark.

 

Apart from that no problems.

 

Like @Crossy no need to wire your heavy duty items through the inverter. Both my shower heaters, air-con and a kitchen double socket still on the grid supply.