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Posted
25 minutes ago, Crossy said:

Plan and mark out for 50+ panels. You don't have to actually build supports yet, but it means that there is space for when (not if) you need more power.

I just read this, and it's the same with the place for the Inverter and Battery.

 

Before we are doing ANYTHING, I want the installer to agree on the location, no point in marking the location for the panels if the installer doesn't agree.

 

The steel bought is NOT a waste of money, Steel at the moment is currently only going up in price ????

Posted
3 hours ago, MJCM said:

Thx, that is added to the list for the Solar Installers!!

 

Edit: But for my info, what do I have to look for myself, if they send me the specs of the inverter?

 

Edit2: Is that MAX AC Output power?  Or AC Nominal Power? Or ....?

Here an example of the Inverters! (I was thinking about the SPH5000 or SPH6000 one)

 

growatt.JPG

First you need to add together all the wattages of the equipment's which can conceivably be switched on and running at the same time. In case you don't know, this is on a rating plate which is located on the back/side/bottom or somewhere which requires a contortionist to see it. EG tv Power 100W.

If this total power is more than the AC Nominal Power then you have two choices.

  1. Get a more powerful inverter.
  2. Make some hard and fast rules about what can and cannot be running at the same time.

The Max. AC apparent power is to do with power factor which, in your data sheet is the same so Power factor = 1 which is fine.

 

Things which might be running at the same time could include shower, water pump, fridge and toaster, and while the kettle is on wifey pops out to water the garden.

 

I have an 8kW inverter which is more than adequate for my home

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Posted

^ Good Info!!!

 

May I ask what happens if you use more power in the house then the inverter is rated for?

 

Why am I asking, is because we have a 6kW Water heater and that is already on his own a big draw, so that Water Heater and the Water Pump and our 18k BTU bedroom Aircon this IMHO will be already more then the 8kW Inverter when used together (and not even talking about my wife watering the garden while I am taking a shower)

 

FWIW. We are on a 15/45 Supply! And Incoming HAS never tripped. All major appliances are on RCBO breakers.

 

Outside of the house (incl Garden Pump) has it's own Fuse box (in the garage (again all with individual RCBO breakers) with a 32a incoming (from the HOUSE). Also never tripped!

Posted
43 minutes ago, MJCM said:

May I ask what happens if you use more power in the house then the inverter is rated for?

The inverter output will stop either by an overload cutout which would need a manual reset after the overload has been removed or catastrophically by destroying the output stage....... You might like to avoid that.

Most inverters do have an overload capability built in. It is normally something like double load for a couple of seconds to allow for startup inrush of motors. This is normally in the spec. I didn't notice that in the specification you showed us but that doesn't necessarily mean it's not included.

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Posted
55 minutes ago, MJCM said:

We are on a 15/45 Supply! And Incoming HAS never tripped. All major appliances are on RCBO breakers.

Your maximum power at 45Amps 220v would be 9.9kW. I would think the meter would allow a bit more for short periods but that's really Crossy's department.

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Posted (edited)
1 hour ago, MJCM said:

Why am I asking, is because we have a 6kW Water heater and that is already on his own a big draw, so that Water Heater and the Water Pump and our 18k BTU bedroom Aircon this IMHO will be already more then the 8kW Inverter when used together (and not even talking about my wife watering the garden while I am taking a shower)

You don't need to have everything wired through the inverter.

Leave all the 'high draw' items on the regular grid power.

It's just silly to try and put everything through it.

 

My future plan was to leave the Air-con and showers on the existing fuse box.

And put all the lighting and sockets through the solar fuse box.

 

And if you want to protect your 8KW inverter from overload, just put a 32A fuse on the output.

(or 25A if you want to leave yourself a safety margin)

 

Edited by BritManToo
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Posted
33 minutes ago, BritManToo said:

You don't need to have everything wired through the inverter.

Leave all the 'high draw' items on the regular grid power.

It's just silly to try and put everything through it.

 

My future plan was to leave the Air-con and showers on the existing fuse box.

And put all the lighting and sockets through the solar fuse box.

 

And if you want to protect your 8KW inverter from overload, just put a 32A fuse on the output.

(or 25A if you want to leave yourself a safety margin)

 

Yeah! I switch over to PEA when running big amps things. I will be making some more permanent wiring to do that some time in the future.

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Posted
10 hours ago, MJCM said:

May I ask what happens if you use more power in the house then the inverter is rated for?

 

The inverters that you are looking at are grid-tie hybrids so if you go over the inverter rating the balance comes from the grid, all totally seamless so you need do nothing.

 

What you will have to consider is what you want to run from the "essential" (UPS) power output which is limited to 3kW on those inverters.

 

Have a look at my pinned thread on inverter types.

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Posted (edited)

So what you guys are saying is that even with Solar you will still import from the PEA because not everything can run from the Solar and the Batteries?

 

For example so my wife thought of getting the new Aircon (24k BTU) and having it run a lot of the time will actually increase our PEA Bill?? Because it can't run via the Inverter together with for example the 2HP garden pump and the 18k BTU in the Bed room? Am I Correct in this?

 

So to solve this (and run everything in the house (maybe not the 6KW water heater) I would need a Bigger Inverter? 10kW and not the 5kW I was thinking?

 

Our goal in the end is to lower the PEA BILL (hopefully to almost Zero) even with added appliances!

 

Real food for thought this! And I guess I need a re-think!

Edited by MJCM
Posted
2 hours ago, Crossy said:

What you will have to consider is what you want to run from the "essential" (UPS) power output which is limited to 3kW on those inverters.

Aircon in bedroom only and Water Pump in the house! Or if too much draw only the sockets so we can run Fan's!

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Posted
20 minutes ago, MJCM said:

So what you guys are saying is that even with Solar you will still import from the PEA because not everything can run from the Solar and the Batteries?

 

It depends!

 

If you use the inverters you are considering :-

  • If solar matches the load everything works off solar.
  • If solar is greater than the load then the batteries charge.
  • If solar is less than the load things are topped up from the batteries.
  • If the load is greater than what's available from solar/batteries the balance comes from the grid.

This post shows how our on-grid hybrid goes about its business:-

 

 

 

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Posted
24 minutes ago, MJCM said:

Our goal in the end is to lower the PEA BILL (hopefully to almost Zero) even with added appliances!

 

What you are considering will do just that IF you have enough panels and big enough inverters.

 

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Posted (edited)
18 minutes ago, Crossy said:

 

What you are considering will do just that IF you have enough panels and big enough inverters.

 

So to be on the safe side, I need to amend the quote request and instead of 1x 5kW inverter I should go for either 2x 5kW or 1x 10kW.

 

But that gives me another question. If a 5kW Inverter is limited in the supply of Power how are 2x 5kW inverters going to handle that? Wouldn't be better to have a single 10kW Inverter or do those 2x 5kW work together to handle the load/double the load?

 

I now really can see that this is not as straightforward as I thought!!

Edited by MJCM
SpElLiNg
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Posted

Your 2 x 5kW will share the load quite happily. We have 1 x 5kW and 1 x 6kW which work together just fine.

 

2 x 5kW will also:-

  • Give you extra MPPT inputs.
  • Double your available battery charging current.
  • Should one fail you still have the other doing it's job.

 

 

 

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Posted

I suspect Mrs. MJCM sees solar as limitless free energy to which many power hungry things can be added at no extra cost. Solar is not like that. It is a finite bespoke source of power tailored to meet demand. If more is required then change needs to come about to accommodate the additional requirements. This is why we add excess panels, batteries and inverters ready for the future. I would also add that there needs to be some consideration for why we want an air conditioner when we used to use an adequate fan. Why use a 2 horse power pump when half a horse is sufficient and so on.

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Posted
6 minutes ago, Crossy said:

Your 2 x 5kW will share the load quite happily. We have 1 x 5kW and 1 x 6kW which work together just fine.

 

2 x 5kW will also:-

  • Give you extra MPPT inputs.
  • Double your available battery charging current.
  • Should one fail you still have the other doing it's job.

 

 

 

I would just add that the multiple inverters are coupled together so that there is no conflict between them. This is a design feature specially for making bigger systems easy to do. Note in a previous comment by Crossy, there is no guarantee that todays inverter can be coupled to a newer version of the same model in the future.

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Posted (edited)
5 minutes ago, MJCM said:

2HP power pump is needed because she is adding more Sprinklers more garden hose (yesterday she ordered another 200 Meters of Garden hose) etc etc. Her garden is growing by the day!! She is now spending 2 hours in the morning and 2 hours in the afternoon watering the garden!! (As already said she is going through almost 4000 Liters of water for her garden and I think coming April it goes up to 5000 Liters so that is why I am so glad we have that Solar Pump to feed the Holding Tank!!) (Ps: the Food she grows is not for sale, but she gives it away to the temple/friends etc etc)

You have a solar pump for the storage tank already so get another for the sprinkler system. Make the garden independent from the house power.

ps. I dare not let my wife see that lovely picture of your garden. She is sure to get ideas......

Edited by Muhendis
new information
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Posted
Just now, Muhendis said:

You have a solar pump for the storage tank already so get another for the sprinkler system. Make the garden independent from the house power.

I have already thought of that!

 

But FYI,  just read this topic!!

 

 

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Posted (edited)
24 minutes ago, Muhendis said:

ps. I dare not let my wife see that lovely picture of your garden. She is sure to get ideas......

5555555 Thx.

 

This is just a small part of it.

 

She is spending lots and lots of time in there, and everything she plants grows and grows! But it was a lot of  trial and error. She mixes her own compounds of soil together to give the seeds a great start in life! Also almost all of our left over food (except Chillies) is put in big tanks and mixed and end up as fertilizer for her plants! (Naam Mak - น้ำหมัก) (I call it Smelly s....t ???? )

 

Edit: Some veggies she is preparing for her daughter to take back to BKK today

 

 

veg.JPG

Edited by MJCM
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Posted (edited)

One more question for you guys.

 

I have been looking through all the Inverters in the PEA approved list and 99.999% (to be precise only 1) of the 10 kW Inverters are for 1 Phase Electric the rest is for 3 Phase!

 

So with @Muhendis saying this.

 

20 hours ago, Muhendis said:

Your maximum power at 45Amps 220v would be 9.9kW

Can I go safely (for example of course) with 2x 6kW Inverters?  The reason why I am asking is that 2x6 will exceed the 9.9kW. Or am I thinking wrong?

 

Edit: the inverters I am looking at, have a AC nominal (output data) of 6000 Watts

 

Please note: We have a NON backwards spinning meter, so we really to have to plan this so that after spending (excuse my language) ....loads of money we are NOT stuck with a higher PEA Bill because of running the AC's 24/7 :whistling:

 

Thx guys! Really really appreciated

:wai:

Edited by MJCM
Posted
1 hour ago, MJCM said:

Or am I thinking wrong?

Yes, I think you are.

 

1 hour ago, MJCM said:

Your maximum power at 45Amps 220v would be 9.9kW

The above refers to the maximum power from PEA according to the PEA meter on the post outside your property. It's a 45Amp meter so the maximum power is the voltage (220v) multiplied by the maximum current (45Amps) which equals 9.9kW. the power you can generate is down to your solar panels, batteries and inverters. If you can generate 12 kW then that is what you can use and it is not limited by the PEA meter.

Having said that, if both of your inverters were to stop working for any reason, then required power would be supplied from PEA through their meter which would limit your maximum power and would require you to watch your consumption to make sure you don't exceed what the meter can supply.

This really needs input from Crossy who is the expert on things PEA.

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Posted
3 minutes ago, Muhendis said:

Having said that, if both of your inverters were to stop working for any reason, then required power would be supplied from PEA through their meter which would limit your maximum power and would require you to watch your consumption to make sure you don't exceed what the meter can supply.

Fully understood, but in the case, if I use more then the PEA supplies through their meter and both my Inverters would stop working, wouldn't then the INCOMING breaker trip??

 

Or am I again overthinking this? ????

Posted
2 minutes ago, MJCM said:

Or am I again overthinking this?

 

Yes, I think you are.

 

Let's do some real numbers.

 

What do you anticipate running at night?

How big an A/C? (will it be running 24/7?)

 

How about during the day?

 

You need enough panels to provide your daytime usage plus get enough into your batteries to support the night.

 

If you go grid-tie hybrid (set to not export) there's no need for more than 1 night of battery, if you don't get enough charge then you just draw from the grid.

 

 

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Posted

Main usage will be

 

- 18k BTU Daikin Inverter (latest model) running from 6pm-8am (but sometimes (during Holidays) running almost 24/7 (Max draw is AFAIK 1300 Watts)
(Model is FTKM18NV2S)

- 0.75 HP Inverter House Pump

- 1 HP (at the moment) Garden Pump (running a lot)

- Fridge (22q) 2 door Hitachi Inverter (attached to a 300 watt UPS) (24x7)

- PC (attached to a 850 watt UPS) (running 16 hours a day)

- Router and 3BB Fttx modem (attached to a 300 Watt UPS) (24x7)

- 2 Drive NAS (attached to a 300 Watt UPS) (24x7)

- 4 Drive NAS (attached to a 300 Watt UPS) (24x7)

- 65" LED TV (attached to a 300 Watt UPS)

- 50" LED TV (attached to a 300 Watt UPS)

- NUC & AppleTV (attached to a 300 Watt UPS)

- during the HOT season 2 or 3 big fans almost constantly during the day in the living room (that's why the wish for aircon)

 

And of course the 6kW water heater!!

 

The reason we have so many UPS is because we have electric cuts that last from 1-10 secs and that coming back of the power is AFAIK can kill those appliances!

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Posted (edited)

It's 18:30+ now and pitch black and my wife still hasn't finished watering her garden!!

 

So when the 1HP (or 2HP) garden pump is connected to the Batteries/Inverter it will be draining them as fast as ..... ????

Edited by MJCM
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Posted
1 hour ago, Crossy said:

All good fun innit? ???? 

For you it is ????

 

Thx :wai:

 

We are far from that usage, our average usage is now (but it's cold) is around 12kW a Day, sometimes even less!!

 

The only thing what I (at the moment) don't understand is this

 

1 hour ago, Crossy said:

Our 10kWP is split into 2 * 1,980W + 1 * 2,970W + 1 * 3,300 strings.

Why is that?

Can't you make 1 string?

 

1 hour ago, Crossy said:

maybe not bother with multi-direction arrays

Understood!!

 

Thx a lot @Crossy

 

:wai:

 

 

Posted

@MJCM  In my totally layperson capacity, I would concur with @Crossy regarding not bothering with having just 2 panels facing East and another 2 facing West as you're possibly going to tie up one of your valuable inverter input ports and only produce a small amount of power.

 

I note from one of your earlier posts that you mentioned 'X' number of (330W) panels to give you the power output that you are hoping to achieve.  I trust that you have taken into account that the panels are going to suffer efficiency losses. 

 

When I designed my small scale car port system, I worked on a potential of 25% efficiency loss.  I wanted my system to be capable of producing approximately 7 units/day which should then reduce my bill by 75%.  To achieve this I installed 4 x 415W mono half-cut panels, which in theory should be capable of producing 1.66kW but taking into account potential efficiency losses of 25% this would come down to approximately 1.2kW.  Assuming 6 hours / day of good sunshine (fingers crossed), 6 x 1.66kW = approximately 7 units /day.  So far the system appears to be on course for 7 units /day and my bills have been reduced by 75% as hoped for.

 

So how is the 25% efficiency loss arrived at?  Take a look at the attached which I found very informative when doing my initial research https://diysolarshack.com/10-solar-pv-system-losses-their-impact-on-solar-panel-output/

 

FYI... The photo below shows the temperature of my panels at mid day on a good sunny day.  The thermal temperature gun is not the most scientifically accurate device, but I think gives a reasonable indication as to how hot the panels can become and lose a fair percentage of their efficiency.

 

20220107_140900_iv.thumb.jpg.62ae1e675e3d50a0e27502043b98fa3d.jpg

 

Good luck with your project.

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