Solar - General

[Pink7]

39 minutes ago, Bandersnatch said:

 

There is rain and there is rain!

 

 

 

I was thinking same when i writed the reply. last week there was rainy/claudy days but still some sun at times and i was able to produce some power and even charge batteries. But right now im producing 0 watt. Im surprised how much power i can produce in a cloudy day without much sunny weather. If I had managed my power usage a bit better i guess I could manage a day or 2 more with my 2 x 280A (30kh)

 

A funny thing i noted. I see my wife checking battery capacity on here phone and adjust usage after the capacity.

 

Pink

 

 

Edited October 30, 2023 by Pink7

[MangoKorat]

8 hours ago, patman30 said:

one thing that would be good to know is your budget?

I don't have a budget as yet.  When I decide on the type/size of system - that will form my budget.  The only thing I know is that I will definitely be going solar but just what that system might be, I am undecided.  I could install a complete system that will produce all my electricity or it is possible that I will only install a system that will produce enough electricity to take care of the additional airconditioning that I will inevitably use.

 

I would state that despite spending the majority of my working life in the motor trade, I went to university late in life moved into construction.  Whilst I leave the ins and outs of electricity etc. to professionals, I have a basic understanding of all aspects of construction.

 

I'm sure we've all heard the stories about Westerners moving to Thailand and building a house for 1 million baht.  Well that may well be possible but that depends entirely on the level of fitments you require and the quality of them.  For example, I installed a Western kitchen and UPVC windows and doors in my current house. The cost of those two items alone was over 500k and the kitchen was far from the top of the range.  I've seen some of these 1 million baht houses and I would not want to live in one.  Therefore, I need to firstly decide on my requirements and in terms of solar, decide on what type of system I want. That will form my initial costing and I will then look at ways of 'trimming' that cost, if necessary as I always did when project managing in construction. I am aware that I could easily spend 5 or 6 million baht constructing the house I want but I won't.  My initial thoughts are a target for the build of 2.5 million but I'm flexible both ways on that - 'flexibility' though, has an uncanny way of usually meaning more :-).

 

I am also trying to make sure that whatever system I choose, will not be a burden to those I leave behind.  To that end, I think an easily switchable PEA connection is vital as from my experience, Thai people very qiuckly 'revert to type' once a Westerner is out of the picture.  In other words, should the solar stop working for whatever reason, I very much doubt it will be fixed or that cash would be available to fix it.  Electricity will though, always be needed. That it is unlikely to be fixed is not really a criticism - how would you be able to replace a set of batteries for example, on a salary of 15,000 per month? Cost is undoubtedly the main reason why very few Thai's install any meaningful solar systems.

[MangoKorat]

9 hours ago, Crossy said:

A few thoughts: -

 

As you are DIYing you will never get approval to export to the grid. This being the case I'd go for a hybrid inverter which can run in parallel and also do grid-sync.

• Do perform an energy-audit.
• Panels are relatively cheap, so don't skimp. 
• Batteries are not cheap, but can be easily expanded if you need more run time.
• Aim at having your panels on a car-port or ground mount if you have space unless you design your home with a flat and accessible roof area (see @Bandersnatch threads and home photos).

Now you've thrown the cat amongst the pidgeons. Coming from construction, a flat roof is a big no no for me - I'm immovable on that, they are nothing but trouble.  However, I understand the need for access to/cleaning of the panels and this is something I hadn't given much thought to so far - now it seems crucial.

 

What we will be building is essentially a farmhouse with some outbuildings around it. Although we have a blank canvas of around 8 rai on which to build, every sq m given over to the house is one that is lost to production and the land is very productive.  We are very fortunate that the southern aspect of the site looks out onto beautiful open farmland and that is something I don't want to compromise - the outbuildings must stay behind the house.

 

I had imagined that the solar panels would easily be incorporated into the south facing roof but that now needs some thought. Whilst it may be possible to design a roof that can be accessed - there will be a cost associated with that. The outbuildings will clearly be shaded by the house so are probably not suitable and may not be large enough. However, as can be seen on the plan below, there will be an area to the left of the house that will incorporate the septic tank and soakaways - that land falls away from the house site naturally so is ideal for this.  I suppose it would be possible to use that area for ground sited panels and thereby not wasting land?

 

Forgive my ignorance but is there a calculation that gives kwh per sq m of panels?  As I say, I'm undecided on the amount of electricity that I wish to produce but its probably better to look at producing all that is needed, I can always work backwards from that - I'm guessing but would 10kwh be sufficient? How many sq m would be needed to produce that amount?  My neighbour in the UK has ground sited solar panels - in the field behind my house and I've always hated looking at them - now I'm considering doing the same myself 😁.

 

I have not given sizes on the plan below as they are undecided but take it that the house will be around 15m x 9m. It will be 'up on stilts' with the vast majority of liveable space on the first floor. My current house is like that and I quite like the arrangement - parking under the house etc. I plan for 2 bedrooms (en suite), an open plan living room/kitchen and some storage space on the first floor with a large balcony looking out over the farmland. It is likely that there will be a further bedroom (en suite) and a laundry room on the ground floor so not tiny but not a really large house. Other than aircon on for most of the day, I don't think my lifestyle is any different to most people so I guess I'm 'average' in terms of electricity useage.

 

As an aside for the moment, the only way that I may differ from 'average' is that I may well have a car lift in one of the outbuildings.  Lifts are predominantly 3 phase so I doubt I can be entirely off-grid.  I don't at this stage, even know if 3 phase is available in the location.  Single phase lifts are more readily available in the UK nowadays than they used to be so I guess they are also available in Thailand.  Anyway - just something to keep in mind for now and its a 'would like' rather than a 'must have'.

 

 

 

Edited October 30, 2023 by MangoKorat

[xtrnuno41]

14 hours ago, MangoKorat said:

Unless I'm really missing something, what is the point of all the energy saving measures you mention if I'm running on solar? How, for example, is the hot air produced by the aircon units a waste?

 

That's been the main driver for me from the start - that I could enjoy basically free aircon by installing solar without an impact on the environment. If I can also utilise that system to provide the majority of the other electricity I use, that would be great, however there are other considerations that need to be taken into account.

 

Some environmental concerns are extremely difficult to measure and there are many differing viewpoints on them.  For example, I once spent almost a whole day weighing up the real environmental benefits of an electric car.  After reading many opposing (scientific) views I was very confused but concluded that they are not the panacea that some claim they are.  It appears that the total environmental benefit of electric cars can take far longer than that which is promoted. A great many things must be taken into account before proclaiming that they are our saviour.  For example, whilst one benefit is that air polution in cities will be greatly reduced, huge amounts of chemicals are currently being injected into the hillsides of the rain forrests of The Congo in order to mine the raw materials used in EV battery production.

 

Of course, our governments and the car companies don't show that, nor are the millions of animal/insects that are being displaced by that mining illustrated on their glossy brochures. To a degree, many of the environmental measures that are currently being taken to combat climate change, appear to be simply shifting the damage from one continent to another. I'm not at all sure that mankind has learned anything from the mistakes of the last 270 years or so - other than to move the problem out of sight.

 

Given the years I have left, I have decided that my current position on vehicles is the best for both myself and the planet.  I run my vehicles for many years and repair them rather than replace them.  I keep my journeys to the minimum and I run vehicles with small to medium sized engines. The exception (in a small way) is my motorbike which is a 650cc - that's down from my last one which was 900cc - I want to at least have a little fun.

 

Then there's the claims regarding recycling.  Batteries may be able to be recycled but what % of them, and will the cost of recycling mean that they are not recycled at all? Cars contain a hell of a lot of plastics these days and regulations state that those plastics must be able to be recycled.  Will they be?  A lot of local authorities in the UK paid companies in Turkey to take away their plastic waste and recycle it.  It was later found to be being dumped in Turkish landfills.

 

I could go on and on but that takes us way to far down the enviromental route that I was trying to avoid. I have concluded that moving to solar generated electricity, using a system that incorporates the minimum of equipment and equipment that is long lasting - is a no brainer compared to power stations belching out smoke etc.  Solar farms are not the answer either - the world is going to face a food shortage before long and we need all the agricultural land possible to provide that food.  In my opinion, the correct place for solar energy systems is on the roofs of existing buildings or possibly in deserts that do little else.

 

That's about all I have to say on environmental matters, I'm confident that I will significantly reduce my own environmental impact by going over to solar and in doing so, make my life more comfortable - all I have to decide on is the battery issue.  I'm completely on the fence on that one - there are a lot of things to take account of and I'm still in the planning stage.

 

 

An airco is cooling one room and the heat is going out to outdoor unit. You dont do a thing with that heat (it is waste), so you could reuse it. Yes, if you have enough solar panels, you can keep your electric heated solar heater of 1.4 kW and forget about the challenge to make foot print smaller. Your 1.4 kW heater, when it starts, needs already 4 panels of 400 pW cables and inverter and then the sun really needs to shine.

But your airco(s) is(are) producing heat and you do take part of heating earth with it. The hot air is blown in the wind.

And not only your airco is doing that, there are billions of them.

So is it environmental thought or just free "easy" power?

 

The solar heater I showed is purely based on heat of sun, so no electric power.

Even Bandersnatch has put such a device to his installation.

If you heat up with sun, no solar panels, no inverters, no cables, so footprint smaller. Maybe even cost you less.

It is about how far you want to go. The challenge. Yes , maybe you also need to change those tubes in it, it also has a lifespan.

 

We used light (wire)bulbs once, majority of power was in heat and so wasted. LED lights made it different, though they are still producing wasted heat. Your car, motor bike all produces wasted heat. It is like that.

Even if you cook wrong, you waste heat, energy.

Btw your bigger motorbike could be more efficient then your smaller one. Mileage to consumption rate. Bigger bikes have mostly some more comfort. My last bike was a Suzuki bking, however didnt mind mileage, was my fun.

My car is now 20 years old with only 73000 km on it. Life changed and not much driving, mostly went to work on bike.

Was better then standing in traffic and "healthier", it is a real crime in my place. 

My car is doing ok, so why replace it? Im already almost not using it, but she has a house for herself.

My Thai wife has Vios, 20 years old, almost 300000 km on counter. However starts to cough now, but still running.

 

Solar panels also have a lifespan of 20 years or so, they say. In time efficiency will go down, also depending on quality and you need to replace them. Try to find some graphs of them. Efficiency to time, temperature, temperature factor(loss of efficiency)

As mostly there is only heat from sun which will effect lifetime. But maybe good?, as they may have developed better ones in time(they still improve). Now they are making window glass included with solar energy, or very flexible panels with almost no weight. However you could end up, building your installation again. As new and old ones will of course not be inter changeable. That is business.

 

You can use an electric car for battery, 2 hits in one blow. You can drive with own generated power and feed back to your system. However those cars arent that cheap. Also red not long ago, a Scotsman had to replace his batteries of his Tesla of 8 years old. Costing him 20000 $. Seems Tesla to have problems with water getting in battery compartment and destroying all. They are investigating. But 20000$ to change ! I wonder what it costs with other cars, otherwise you buy "throw away" cars. You will buy an electric car of 5 years old? Yha, maybe for 1000$ , not more. 

 

Climate change and changing to other systems is also just business and nothing more. We destroy our home and after all it is just about the money.

PET bottles can be reused, in "my" country we do have a factory doing that. However the bottles cost some more, dont know how much, then a new made bottle from chemicals.

So if you need 1 million (per 3 months?) bottles and difference is just 1 cent, what you think (soda,water)manufacturers will choose?

You save 10000 $ as manufacturer on each million bottles. So easy sum, take new bottles.

Otherwise you cut chemical producer in fingers. So where to go? Environment or money?

For now system is all about money. Only YOU can think different and do so for your self and maybe activate others.

 

In "my" country, we already have a lot of solar panels, really increased due to war. Sometimes they CANT give back to grid, it will be blocked, probably something inverter is doing. There must be a communication possible in inverters to shut them down in delivery.

And now even the time has come, power suppliers want you to PAY for delivering to grid ! They cant sell the power they bought, so then you have to pay for delivering to grid. Nice hey.

In fact now is showed, you MUST invest in batteries.

 

Next problem, people with no solar will have to pay more for their unit, as otherwise selling company goes down in  profit. Real battle for providers, but the people with no solar will pay more. Till those also decide to go for panels, a must then. 

Then power companies get in trouble, as their machines are made for special working point and it is not tolerated to go up or down much. Gas-, steam turbines, spinning high speed. They have to get smaller.

And then we have nucleair fusion and all can go to scrapyard.

 

Government is now also busy with making H2 from windmill power. As in north of country they were making too much electricity!! ?? Of course first for companies relying on natural gas.

Then probably way later for the rest, maybe.

With the coming of H2, also more cars will be driving on H2. First now fuel cell and maybe later combustion again.

Or still combustion, as they can make fuel from CO2 and H2, circulating then. However proces will take quite some energy.

Making oil, petrol from asfalt is a proces on 200 bar and high temps. Also adding H2 to asphalt atoms.

Must have been worthwhile to do, to increase profit.

 

I still dont understand why Sahara isnt in a project. Well maybe it is, but I dont know.

We want to keep diversity and animals. How is Africa effected on climate change?

Otherwise also that is going down and wild life preserving was all fake.

Of course, what about the people? With the technolygy we have, we can make fresh water, power, H2 over there !

OK, I stop, already too long and just keep on thinking and writing.

 

 

[MangoKorat]

36 minutes ago, xtrnuno41 said:

But your airco(s) is(are) producing heat and you do take part of heating earth with it. The hot air is blown in the wind.

And not only your airco is doing that, there are billions of them.

So is it environmental thought or just free "easy" power?

Look, we could get into a really deep debate and essentially, I agree with you.  My thoughts overall on climate change is that the problem stems from the fact that there are just too many people on the planet but that's a different debate and something that is just about impossible to deal with. None of that really has a place here - I am trying to deal with things as they are and not how they can be.

 

However, I take on board your comments on heat recovery and will give it some thought as to what, if anything, I can do about it.  The water heater you suggest would indeed provide hot water 'for free' at some times of the day but it wouldn't work 24/7.  Heat recovery is a growing item in Europe but it only works in built up areas where many sources can be incorporated and then it is used for heating. I'm looking for cooling. I don't see how I could make it work in my plans. Simply saying that I could use the heat from an air source heat pump to compliment the solar water heater is easy - doing it is a different matter.  Air source heat pumps are large cumbersome machines whereas I believe solar water heaters are best placed on a roof - I can't immediately see a way around that but I will look at it.

 

My thoughts on using solar are genuinely environmental - how would it be if like the majority (currently), I simply installed aircon units and ran them 24/7 using grid electricity that is produced using predominantly fossil fuels? Or should I simply sweat?  How would it be if a ran a 3.2L V6 engined truck rather than the 1.4L hatchback I currently run to simply get one person from A to B like so many do?  I do what I can and please remember, that the environmental measures I will incorporate into my new home will have a significant cost - a cost that I am unlikely to recover. That, whilst huge amounts of energy are being wasted all over the world.  Think about internet servers that enable our youth to constantly surf on their phones needlessly. 'The Cloud'  that uses massive amounts of electricity to enable businesses to store their data without the need for huge hard drives, display lighting in city centres where nobody goes etc. etc.

 

Sorry but I think that what I am planning is entirely good for the planet. It may not be the best I can do but it is 100% more than the majority of the earth's population is doing.

Edited October 30, 2023 by MangoKorat

[xtrnuno41]

SO you cant do anything with the septic tank/soakaway area? Make a garage/inverter/ batteries room/?

On top of that building then your solar panels? With a stair up for acces for cleaning panels? 5x 10 mtr?

Panels on a (construction) slope of 15 degrees or so? panels are  1754 x 1096 centimeter

Slope not too high, because of making shades. Panel cant create shade for other panel behind it.

Slope so rainwater can go off and take dirt with it.

Car(s) on north side? 4 panels in a row and then +/-10 meters to the back, also maybe 4/5 rows, is 16/20 panels of 400pW.

 

[MangoKorat]

1 minute ago, xtrnuno41 said:

SO you cant do anything with the septic tank/soakaway area? Make a garage/inverter/ batteries room/?

You clearly don't understand. I am suggesting/asking if I can place solar panels over my septic tank/soakaway area and if so, how many sq m of panels would be needed to supply my house.

[xtrnuno41]

54 minutes ago, MangoKorat said:

You clearly don't understand. I am suggesting/asking if I can place solar panels over my septic tank/soakaway area and if so, how many sq m of panels would be needed to supply my house.

Sorry to upset you and making you grumpy with environmental issues. This will be my last respond.

I just gave you a bit of solution, up to you.

How many panels you need, I cant say. It is depending on how much power you use.

I would recommend seeing Bandersnatch's eco page, then you have an impression, I think.

He has 10 panels of 535 pW and 32 panels of 350pW.

For the bigger panels the size is different 2384×1096×35 mm (93.86×43.15×1.38 inches).

Include a datasheet of a panel: 

https://loopsolar.com/datasheet/trina-solar/datasheet-trina-solar-mono-crystalline-110-cell-535Wp-540Wp-545Wp-550Wp-555Wp-with-backsheet.pdf

 

Dont know what are the outbuildings and how big, m2. Make them high enough to prevent shade of house (1 story, 2 story house?) and also put solar panels on them with inverters in building?!. 

 

@Bandersnatch compliments of showing all.

Nice he is showing temperature difference between painted and non painted wall. All the effort of isolating.

Sadly also some panels are in shade of house and doing less at times.

 

Succes MK

 

[lom]

43 minutes ago, MangoKorat said:

You clearly don't understand. I am suggesting/asking if I can place solar panels over my septic tank/soakaway area and if so, how many sq m of panels would be needed to supply my house.

How long is a rope? 

You are the only one who can decide how many panels you need which is mainly based on your power consumption between 07-17. The size of a single panel and its power rating is available from the seller or you can google it for a specific panel. Reduce 10% of panel power to compensate for losses. Choose an all-in-one off-grid hybrid inverter which can run in grid-tie mode, it will produce up to its limit (or panel power limit) for your house use and if that is not enough then it will take the reminder from the grid. If the inverter dies after you die then everything will be as if you've never had an inverter, your family will get a PEA bill for every KWh they use. No need for an electrician to come and scratch his head..

If you are thinking of adding batteries then it can be done later but then you may need more panels depending on how much battery storage you choose and how fast you want to fully charge them. 07-17 is daylight but best solar power is between 9-15.

 

My system is 16 455W panels in W, 16 455W panels in east and a Deye 12KW 3-phase hybrid inverter and 25KWh of batteries. The batteries covers the time 17-07 and are down to 25% at sunrise, then I usually have enough panel power between 07-08 to start charging them again while at the same time produce enough for the house consumption. Batteries are usually full right after midday.  Then comes the rainy season and make havoc of all your plans and calculations...

[MangoKorat]

4 minutes ago, lom said:

How long is a rope? 

You are the only one who can decide how many panels you need which is mainly based on your power consumption between 07-17.

If you read my posts fully you will see that I was asking if 10kwh was a reasonable assesment for an average house.

[MangoKorat]

6 minutes ago, lom said:

The size of a single panel and its power rating is available from the seller or you can google it for a specific panel. Reduce 10% of panel power to compensate for losses.

I would rather have real world figures - given by people living in Thailand. We have several members here who have long standing solar installations.

[lom]

2 minutes ago, MangoKorat said:

I would rather have real world figures - given by people living in Thailand. We have several members here who have long standing solar installations.

I've told you what I have and I've also informed you of the variables involved.  Start with reading your PEA meter at sunrise and sunset for a couple of days, mixed rainy and sunny, so you get an idea of your power consumption. Then decide how much of a 24 hour day you want to cover with panel power (and battery power).

With that said I'm now leaving your thread.

[MangoKorat]

14 minutes ago, lom said:

I've told you what I have and I've also informed you of the variables involved.  Start with reading your PEA meter at sunrise and sunset for a couple of days, mixed rainy and sunny, so you get an idea of your power consumption. Then decide how much of a 24 hour day you want to cover with panel power (and battery power).

With that said I'm now leaving your thread.

Oh dear, sorry to upset you - I have taken note of your comments but I need to have more in order to provide a balanced view.

 

I cannot measure my usage because:

 

A. I do not currently live in Thailand full time.

 

and

 

B. I have never lived in the situation I will be doing so I don't know how much electricity will be used by other people.

 

I can only work on averages which is why I asked in my reply to Crossy if 10kwh would be appropriate.

 

I think it is probably better to install a system that is capable of providing more than is actually required as I think that in the main, electricity requirements go up rather than down.

 

Please also understand that I have to google a lot of the terminology used here. I have never had any experience of solar power so for example, I have no idea what a Hybrid Inverter is - if I tried to explain how an automatic gearbox works, would you understand?

 

I'm learning but it takes time.

[patman30]

13 hours ago, MangoKorat said:

I don't have a budget as yet.  When I decide on the type/size of system - that will form my budget.  The only thing I know is that I will definitely be going solar but just what that system might be, I am undecided.  I could install a complete system that will produce all my electricity or it is possible that I will only install a system that will produce enough electricity to take care of the additional airconditioning that I will inevitably use.

 

I would state that despite spending the majority of my working life in the motor trade, I went to university late in life moved into construction.  Whilst I leave the ins and outs of electricity etc. to professionals, I have a basic understanding of all aspects of construction.

 

I'm sure we've all heard the stories about Westerners moving to Thailand and building a house for 1 million baht.  Well that may well be possible but that depends entirely on the level of fitments you require and the quality of them.  For example, I installed a Western kitchen and UPVC windows and doors in my current house. The cost of those two items alone was over 500k and the kitchen was far from the top of the range.  I've seen some of these 1 million baht houses and I would not want to live in one.  Therefore, I need to firstly decide on my requirements and in terms of solar, decide on what type of system I want. That will form my initial costing and I will then look at ways of 'trimming' that cost, if necessary as I always did when project managing in construction. I am aware that I could easily spend 5 or 6 million baht constructing the house I want but I won't.  My initial thoughts are a target for the build of 2.5 million but I'm flexible both ways on that - 'flexibility' though, has an uncanny way of usually meaning more :-).

 

I am also trying to make sure that whatever system I choose, will not be a burden to those I leave behind.  To that end, I think an easily switchable PEA connection is vital as from my experience, Thai people very qiuckly 'revert to type' once a Westerner is out of the picture.  In other words, should the solar stop working for whatever reason, I very much doubt it will be fixed or that cash would be available to fix it.  Electricity will though, always be needed. That it is unlikely to be fixed is not really a criticism - how would you be able to replace a set of batteries for example, on a salary of 15,000 per month? Cost is undoubtedly the main reason why very few Thai's install any meaningful solar systems.

funny you mention 1 million baht house
as i recently built a house for 1m, but then spent another 1m on solar, well, landscaping etc. lol
although this was not by choice due to the restricted movement nonsense of past few years i had to buy my land and build blind
so built a cheap house with intention of building new after a few years
as you have the budget, you could have a very very decent solar system that will last many years (NiFe batteries being the expensive part)
i too have concerns about solar being fixed in future which is why i plan to buy many replacement parts and store them
and why i will upgrade to NiFe batteries knowing they will never need replacing
for the same reason i want to build next house with shipping containers or box culverts to reduce maintenance costs in future
and so i can do all the interior work myself, including electrics.

[patman30]

9 hours ago, MangoKorat said:

if 10kwh would be appropriate.

10KW would likely be fine for most people
providing you have efficient aircons
what is more important imo is battery capacity for bad days
and if using lithium ideally you don't want batteries fully charged to help longevity,

this is not an issue with NiFe and NiFe can also be fully discharged, whereas Lithium you should shutdown when at 20%

as for panels over your septic tank and soakaway
yes you can but you would likely need more panels than that space provides
i have 30 panels for my 15KW system, panels are roughly 1m x 2m
when planning for your house, design it to have a large flatish roof
you can find the optimal angles online, but most normal tiled house roofs are not ideal

Edited October 31, 2023 by patman30

[KhunLA]

20 hours ago, Pink7 said:

 

I was thinking same when i writed the reply. last week there was rainy/claudy days but still some sun at times and i was able to produce some power and even charge batteries. But right now im producing 0 watt. Im surprised how much power i can produce in a cloudy day without much sunny weather. If I had managed my power usage a bit better i guess I could manage a day or 2 more with my 2 x 280A (30kh)

 

A funny thing i noted. I see my wife checking battery capacity on here phone and adjust usage after the capacity.

 

Pink

What a crap production day today.  Woke up, and I guess ESSs shy of 60%, as only 68% now.  Just now started producing 2+kWh, (vs 1kWh or less earlier (9.7kWh of PV) so 3-4 hrs of that, and we'll be back at 100% before production drops off to ... not enough 😂  

 

Using less than 300w:

2 frigs

1 fan

65" TV/laptop.   Guess I should be on the phone, too small & annoying to type.

 

Time for a park run with the dog 😎

[MangoKorat]

11 hours ago, patman30 said:

10KW would likely be fine for most people
providing you have efficient aircons
what is more important imo is battery capacity for bad days
and if using lithium ideally you don't want batteries fully charged to help longevity,

this is not an issue with NiFe and NiFe can also be fully discharged, whereas Lithium you should shutdown when at 20%

as for panels over your septic tank and soakaway
yes you can but you would likely need more panels than that space provides
i have 30 panels for my 15KW system, panels are roughly 1m x 2m
when planning for your house, design it to have a large flatish roof
you can find the optimal angles online, but most normal tiled house roofs are not ideal

Thanks for that - so a plan is emerging.

 

There is no way I would ever go for a flat roof but a single pitch modern design with a low-ish angle sounds like its the way to go. I think that would provide ample space for my requirements and also sufficient access room for maintenance. If I go for that, I may completely change the house design that I have in mind

 

If I install a 10kw system knowing that I might want to upgrade it to say 15kw in the future - are there measures I can put in place when installing the original system that would make an upgrade easier.

 

This my sound crazy - remember I have little knowledge but what I'm thinking is - would fitting an inverter that will cope with 15kw be OK with just 10kw? So a bigger inverter from the start?

 

 

[KhunLA]

27 minutes ago, MangoKorat said:

Thanks for that - so a plan is emerging.

 

There is no way I would ever go for a flat roof but a single pitch modern design with a low-ish angle sounds like its the way to go. I think that would provide ample space for my requirements and also sufficient access room for maintenance. If I go for that, I may completely change the house design that I have in mind

 

If I install a 10kw system knowing that I might want to upgrade it to say 15kw in the future - are there measures I can put in place when installing the original system that would make an upgrade easier.

 

This my sound crazy - remember I have little knowledge but what I'm thinking is - would fitting an inverter that will cope with 15kw be OK with just 10kw? So a bigger inverter from the start?

 

 

Depends.  Hindsight for me, our system, 8kW, (Deye) and probably should have went with two 5kW inverters.  Gives a bit of redundancy, in case one or only, has an oops.   Also, the Deye 5kW is on the approved PEA list of inverters to use, as is their 10kW for 3 phase connections.

 

We don't need 10kW and 5kW wouldn't be enough during a week of crap weather.   Or charging the EVs, which was a complete after thought, and not even considered when sizing the system for the house.   Thankfully produces more than enough for both, and then some on sunny days.

 

Slight angled roof is preferred, or so our installer stated.  When he assessed the job, said very good, not really kissing my butt, as contract was already signed.   Just confirmed my design was a good one.

[MangoKorat]

So Patman30 is recommending NIFE batteries - yet a quick search on these seems to suggest they are pretty old tech. The attractive part for me is that they last over 30 years. 

 

However, a quick Google on NIFE batteries seems to rule them out:

 

https://www.rpc.com.au/solar-news/disadvantages-of-nickel-iron-batteries.html

 

Thoughts anyone?

[MangoKorat]

Jeez, these battery costs are frightening:  Take a look at the information in the link below:

 

https://www.theecoexperts.co.uk/solar-panels/the-best-storage-batteries

 

I need to know that I'm understanding things correctly, for example, my understanding of the spec of the 'best buy' Tesla battery recommended is that I would actually need 2 of them to provide 10kw of power usage??  The batteries are rated at 13.5KWh but the maximum power is stated as 5kw.  The information on the website states that 'most homes should function just fine with a single unit' (Tesla battery) yet the consensus here and elsewhere seems to be that an average home will need 10kw...............no wonder I get confused.

 

At £7450 (328,000 baht) for one Tesla battery - without the 'Tesla Gateway' @ £1480 (65,000 baht), I don't think I'll be using them 😁.

[Muhendis]

21 minutes ago, MangoKorat said:

Jeez, these battery costs are frightening:  Take a look at the information in the link below:

 

https://www.theecoexperts.co.uk/solar-panels/the-best-storage-batteries

 

I need to know that I'm understanding things correctly, for example, my understanding of the spec of the 'best buy' Tesla battery recommended is that I would actually need 2 of them to provide 10kw of power usage??  The batteries are rated at 13.5KWh but the maximum power is stated as 5kw.  The information on the website states that 'most homes should function just fine with a single unit' (Tesla battery) yet the consensus here and elsewhere seems to be that an average home will need 10kw...............no wonder I get confused.

 

At £7450 (328,000 baht) for one Tesla battery - without the 'Tesla Gateway' @ £1480 (65,000 baht), I don't think I'll be using them 😁.

Those sort of prices are scary. 

If you are a bit handy you could make your own battery.

That's what I have done and it's worked out quite nicely over the past ten years or so.

Mind you, I don't use these new fangled lithium things. I am now into my third set of lead acid.

The type I am now using is lead carbon. They have a similar performance to lithium but are considerably heavier.

I could wax lyrical about them but at this time of night I am in lazy mode but you can get a good idea of how they work from this:

 

https://batteryuniversity.com/article/bu-202-new-lead-acid-systems

 

In a nutshell they have better charge acceptance (they charge quicker). Can go to a greater depth of discharge. Don't have sulfation problems. Can live longer in a wider temperature range and have an extended life. This in comparison with "normal" lead acid.

I have a bank of them which amounts to 36kWh at 48V. Their anticipated life span is about 11½ years at30% dod. Price was about 140k Baht and so far they do what they are specified to do.

[MangoKorat]

@Bandersnatch Thanks very much for your input. Sorry that I haven't made much of a comment yet - I wanted to look at your blog first and I'm about halfway through that. Very interesting so far.  I doubt I'm as committed so probably won't go as far you have but there's a lot of ideas in your build that can easily be incorporated into a 'standard' build with little/no cost.

 

Thanks again.

[KhunLA]

ESSs with LFP chemistry will last quite some time, depending on DOD.   

 

Also why we added a 2nd ESS (10kWh) for longevity of the banks.  With 20kWh, they rarely discharge to <60%.  Good for more than a few thousand cycles and still maintain 80% at end of that time period.

 

Realistic ball park, 33% daily, so 1 cycle every 3 days.

5000 cycles = 15,000 days = 40+ years.

2500 cycles = 7,500 days = 20+ years

 

Why not ... 10k = 30k = who cares,

the wife is 47 yrs old already.

source

 

 

Edited October 31, 2023 by KhunLA

[MangoKorat]

2 hours ago, KhunLA said:

ESSs with LFP chemistry will last quite some time, depending on DOD.   

 

Also why we added a 2nd ESS (10kWh) for longevity of the banks.  With 20kWh, they rarely discharge to <60%.  Good for more than a few thousand cycles and still maintain 80% at end of that time period...........................................................

 

 

Please remember I'm a newcomer to solar.  ESS, LFP, DOD??????????

[Crossy]

2 hours ago, MangoKorat said:

Please remember I'm a newcomer to solar.  ESS, LFP, DOD??????????

 

Welcome to the world of the TLA - Three Letter Acronym 🙂 

 

ESS - Energy Storage System - ok batteries.

LFP - LiFePO4 - Lithium, Iron, Phosphate - The safest of the currently available lithium battery chemistries. Much less likelihood of these going whoosh compared with the NMC (Nickel, Manganese, Cobalt) chemistry that has been widely used in electric vehicles (most EV manufacturers are moving to LiFePO4 now).

DOD - Depth of Discharge - how much of the ESS total capacity you actually use.

 

Maybe we need a pinned topic with the common TLAs used in solar.

 

[Bandersnatch]

7 hours ago, MangoKorat said:

@Bandersnatch Thanks very much for your input. Sorry that I haven't made much of a comment yet - I wanted to look at your blog first and I'm about halfway through that. Very interesting so far.  I doubt I'm as committed so probably won't go as far you have but there's a lot of ideas in your build that can easily be incorporated into a 'standard' build with little/no cost.

 

Thanks again.

 

Completely understandable. If you look at the design criteria section I lay out the priorities for the build. This is where you have to make compromises and if you want the most efficient home possible you have to move away from what most people consider attractive in a house. In Thailand that is a house that you would expect to see in North America or Northern Europe with big picture windows. I was lucky that I have a very understanding wife.   

[Bandersnatch]

On 10/30/2023 at 9:57 PM, xtrnuno41 said:

Bandersnatch compliments of showing all.

Nice he is showing temperature difference between painted and non painted wall. All the effort of isolating.

Sadly also some panels are in shade of house and doing less at times

 

I get this question so often that I made a video about it. 

 

 

[patman30]

12 hours ago, MangoKorat said:

Thanks for that - so a plan is emerging.

 

There is no way I would ever go for a flat roof but a single pitch modern design with a low-ish angle sounds like its the way to go. I think that would provide ample space for my requirements and also sufficient access room for maintenance. If I go for that, I may completely change the house design that I have in mind

 

If I install a 10kw system knowing that I might want to upgrade it to say 15kw in the future - are there measures I can put in place when installing the original system that would make an upgrade easier.

 

This my sound crazy - remember I have little knowledge but what I'm thinking is - would fitting an inverter that will cope with 15kw be OK with just 10kw? So a bigger inverter from the start?

 

 

for 10KW system
you would most likely run 2 x 5KW inverters parralel
you can run upto 6 inverters like this
so adding another inverter and panels later is not a big issue

you can get 10KW and 15KW inverters
but if that one inverter has an issue all your power is gone
using multiple inverters, if one has a fault you still have the others for some power while the faulty one gets fixed or replaced

Edited November 1, 2023 by patman30

[patman30]

12 hours ago, MangoKorat said:

So Patman30 is recommending NIFE batteries - yet a quick search on these seems to suggest they are pretty old tech. The attractive part for me is that they last over 30 years. 

 

However, a quick Google on NIFE batteries seems to rule them out:

 

https://www.rpc.com.au/solar-news/disadvantages-of-nickel-iron-batteries.html

 

Thoughts anyone?

most of those disadvantages are non issues
and that article is from a company selling solar systems with tesla powerwall batteries
of course products they do not sell are not as good as ones they do sell in their opinion
1. Cost, yes they cost more upfront but last much longer
2. Efficiency, yes they are not as energy dense, so will be bigger, yes they have self discharge of 1% a day which is not an issue if charging daily, Yes they come in 1.2v meaning you need a lot more cells for your battery again meaning you need more space
3. Ventilation, Yes they release hydrogen, easily resolved with good ventilation, not an issue for a new build that can ensure ventilation is part of the design

4. Compatibility, Of course you need to ensure all working parts are compatible.
5. Size and weight, yes they are big and heavy, again not an issue with new house build if designed to accomodate
6. Maintenance, Yes they require topping up weekly, but this ensures they work for 50 years, there are guides to make auto refillers online and some products coming to market to automate this for you.

for cost comparison, you can find 48v 1200ah NiFe batteries for $450/each
for 40 cells this would equal $18,000, which is ~652,000 THB (before shipping)
i recently purchased a 48v 300ah lithium battery for 81,000 THB
so 4 of these today would cost 324,000 THB

Edited November 1, 2023 by patman30

[Muhendis]

45 minutes ago, patman30 said:

most of those disadvantages are non issues
and that article is from a company selling solar systems with tesla powerwall batteries
of course products they do not sell are not as good as ones they do sell in their opinion
1. Cost, yes they cost more upfront but last much longer
2. Efficiency, yes they are not as energy dense, so will be bigger, yes they have self discharge of 1% a day which is not an issue if charging daily, Yes they come in 1.2v meaning you need a lot more cells for your battery again meaning you need more space
3. Ventilation, Yes they release hydrogen, easily resolved with good ventilation, not an issue for a new build that can ensure ventilation is part of the design

4. Compatibility, Of course you need to ensure all working parts are compatible.
5. Size and weight, yes they are big and heavy, again not an issue with new house build if designed to accomodate
6. Maintenance, Yes they require topping up weekly, but this ensures they work for 50 years, there are guides to make auto refillers online and some products coming to market to automate this for you.

for cost comparison, you can find 48v 1200ah NiFe batteries for $450/each
for 40 cells this would equal $18,000, which is ~652,000 THB (before shipping)
i recently purchased a 48v 300ah lithium battery for 81,000 THB
so 4 of these today would cost 324,000 THB

I looked at NiFe batteries some time ago and the only good thing about them seems to be that they will outlive me.

Far too many negatives especially cost, for general household use.

Also another negative not mentioned is the electrolyte.

I seem to recall there is a requirement to mix up your own electrolyte.

You might like to check out what to do if battery performance decreases for any reason.

"Never happen if you take good care of them" I hear someone muttering but don't forget Murphy's law. Anything that can go wrong will go wrong..

For the domestic home user it really needs to be fit and forget.