Which direction should solar panels face?

[Bandersnatch]

I made this video to answer all the questions I was getting online about my solar system. I was getting lots of friendly advice telling me that I was a complete idiot by not putting all my solar on the south side of my house. Maybe it might be of interest to anyone considering going off-grid in Thailand.  

 

 

 

[FritsSikkink]

They should face the sun.

[Crossy]

14 minutes ago, FritsSikkink said:

They should face the sun.

 

Indeed, and this close to the equator the sun can actually be in the north.

[KhunLA]

My installer told me I had the perfect roof set up for solar.  Planned of course.  3 very slight angled roofs facing E / S / W, so should get excellent exposure all day.  No shading.

 

Probably put 5 / 6 / 6 panels @ 455w on each, for 8KWS w/10kw ESS.  We use 500-700 PEA units a month now, and don't see us using more than 1000 units with the new house.  Hopefully done before end of February.

[Crossy]

4 minutes ago, KhunLA said:

Probably put 5 / 6 / 6 panels @ 455w on each, for 8KWS w/10kw ESS.

 

I'd probably go 5 / 7 / 5 on three separate MPPT controllers to mitigate shading.

 

Please try to use correct capitalisation of units, it really does matter. It's 455W panels, 8kWP (if you are talking the panels) and a 10kWh ESS.

[KhunLA]

2 minutes ago, Crossy said:

 

I'd probably go 5 / 7 / 5 on three separate MPPT controllers to mitigate shading.

 

Please try to use correct capitalisation of units, it really does matter. It's 455W panels, 8kWP (if you are talking the panels) and a 10kWh ESS.

Yea, them letters ...  and yea, thought about the 7 on S side, and installer will probably agree.  When he looked at the house, at first, thought about 5kW system, (no east roof) then 6.3 and now he doesn't even bother with anything smaller than 8kW system, which is good, as original, 2 smaller systems were tie in, wth PEA overnight, now hybrid w/ESS.  

 

I don't want nothing to do with PEA, though for 41 baht a month, will keep for emergency back up ????

[herfiehandbag]

29 minutes ago, Crossy said:

 

I'd probably go 5 / 7 / 5 on three separate MPPT controllers to mitigate shading.

 

Please try to use correct capitalisation of units, it really does matter. It's 455W panels, 8kWP (if you are talking the panels) and a 10kWh ESS.

PDTIA.

 

Please don't talk in abbreviations!

☺️

 

Seriously, I am not very good at electricity (red to red and black to black, switch it on and stand well back is about the norm for me), but at least if you used the full words I might be able to get some sort of a handle on what you're talking about!

[Crossy]

6 minutes ago, herfiehandbag said:

PDTIA.

 

Please don't talk in abbreviations!

☺️

 

ESS = Energy Storage System (battery)

kWh = Kilowatt hour (or unit on your power bill)

kWP = kilowatt photovoltaic (talking abour solar panels)

MPPT = Maximum Power Point Tracking - talking about solar charge controllers

PEA = Provincial Electricity Authority

 

Maybe we do need an abbreviations and acronyms thread.

[MJCM]

19 minutes ago, Crossy said:

 

ESS = Energy Storage System (battery)

kWh = Kilowatt hour (or unit on your power bill)

kWP = kilowatt photovoltaic (talking abour solar panels)

MPPT = Maximum Power Point Tracking - talking about solar charge controllers

PEA = Provincial Electricity Authority

 

Maybe we do need an abbreviations and acronyms thread.

You forgot SWMBO ????

[KhunLA]

28 minutes ago, herfiehandbag said:

PDTIA.

 

Please don't talk in abbreviations!

☺️

 

Seriously, I am not very good at electricity (red to red and black to black, switch it on and stand well back is about the norm for me), but at least if you used the full words I might be able to get some sort of a handle on what you're talking about!

If & when you're doing research for a system, most things are going to be acronymed anyway, so best to know & understand.  It can get really confusing, if trying to 'convert' things from kw kwh ah amps, and a few more, which I probably screwed up anyway.

 

When planning a system, looking at your PEA bill, and units used, is a good guide to start on size of system.  Then consider if having ESS / battery back up for overnight or not so sunny days, then need to know what you'll actually be using.

 

My system, I'm just concerned about overnight (1 small AC & 2 small frigs) of which, you'll only use about 70% of the ESS anyway, so that has to be factored in.  I'll have PEA for any long stretches of clouds, which will also mean, ACs won't be full on all the time.  Overnight now, and dehumidifier mode is usually enough, if that.

 

Hybrid system w/ESS will add a lot to cost, so you need to know you'll be living there long enough for ROI (return on investment), and can be 5-10 yrs depending on system.  Goes with home ownership also, as buying vs renting for less than 5 yrs may also not see a good ROI.  Especially in a buyer's market, as it is now.

[MJCM]

@Bandersnatch

 

Great thread Thx!!

 

Am I correct in saying that for a small system like I am getting (5kW) there is no use of getting some of my Panels aligned to E and W as well and only have them aligned to the S. Or did I misunderstood??

 

 

The Sun in the evening and early morning is I think where in our case most of the profit can be achieved because my wife waters the garden those times (4000 Liter of Water a Day she goes through ???? )

 

Thx again.!

[Bandersnatch]

1 hour ago, MJCM said:

@Bandersnatch

 

Great thread Thx!!

 

Am I correct in saying that for a small system like I am getting (5kW) there is no use of getting some of my Panels aligned to E and W as well and only have them aligned to the S. Or did I misunderstood??

 

 

The Sun in the evening and early morning is I think where in our case most of the profit can be achieved because my wife waters the garden those times (4000 Liter of Water a Day she goes through ???? )

 

Thx again.!

 

I seem to remember that you are getting batteries as well, so you want maximum power production to charge the batteries. I would put you panels south facing.

 

Regarding watering, one or two panels could power a solar pump. Did you see my video on solar irrigation?

 

 

[heybuz]

Towards the equator, north if in the southern hemisphere south if in the northern hemisphere.

[Dazinoz]

In the northern hemisphere for best all year results your panels should face due south and angled at the angle of the latitude where they are located. EG in Chiang Mai where I live the optimal positioning is due south at an angle of 19.9degrees. Bangkok due south at 13.8 degrees.

[Muhendis]

If you want maximum exposure over the year at minimum cost you might consider a tilt arrangement whereby the angle of the panels can be changed to suit maybe three times per year. A bit tricky with a roof mounted system but if it's ground mounted then it might be worth considering.

[MJCM]

1 hour ago, Muhendis said:

If you want maximum exposure over the year at minimum cost you might consider a tilt arrangement whereby the angle of the panels can be changed to suit maybe three times per year. A bit tricky with a roof mounted system but if it's ground mounted then it might be worth considering.

We already have that for our 3 Panels. When I walk over there I will take some pictures.

 

My BIL made it together with his son, the total construction incl the 6 concrete poles (where the structure rests on) was something like 4000 THB. (excl the panels)

 

Here a picture from the distance (will post other pictures later)

 

 

 

[Skeptic7]

Up

[MJCM]

13 hours ago, Bandersnatch said:

I seem to remember that you are getting batteries as well, so you want maximum power production to charge the batteries. I would put you panels south facing.

Thx, Yes I am getting a minimum of 10 kW ESS

 

13 hours ago, Bandersnatch said:

Regarding watering, one or two panels could power a solar pump. Did you see my video on solar irrigation?

Solar Pump for her garden, there is a Whole Thread on here about that, and in the end (due to my technical inability (and also because of the inability of the installer) we still use the 1HP (PEA driven) Pump which after we get the Solar will be upgraded to 2HP.

 

Re: Irrigation and sprinklers etc etc.

My wife loves to do it by hand, she gets up 5:30am drinks a cup of coffee and is watering her garden till 8am approx. And at around 5pm she waters it again and she finishes around 6:30-7pm.

 

 

[JBChiangRai]

Our solar system is grid-tied and we have 3 grid-tied inverters.  One will often shut down because we are outputting too much power to the grid. They are actually cadenced at 2 volts apart.

 

I’ve tackled this with an over voltage sensor and a normally closed (NC) contractor.  When the voltage climbs close to the cutoff point, the over voltage device triggers, opening the contractor and closing the contacts so that my Battery EV starts charging, lowering the mains voltage so the first inverter doesn’t shut down. This can sometimes be as early as 10:30am. The two 2KW stored water systems turn on first at 30 minute intervals delaying the trigger/BEV charging time.  By mid afternoon the air conditioning units are drawing more load, we generally run them dawn to dusk, sometimes 24/7.

 

 

[Muhendis]

11 minutes ago, JBChiangRai said:

I’ve tackled this with an over voltage sensor and a normally closed (NC) contractor.

I was once a contractor but I never imagined myself being normally closed

[JBChiangRai]

15 minutes ago, Muhendis said:

I was once a contractor but I never imagined myself being normally closed

A Priest, a vicar and a rabbit went into a bar, the barman asked the rabbit what he wanted to drink.  The rabbit replied “I don’t know, I’m only here because of autocorrect “

[Troy Tempest]

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

[MJCM]

4 minutes ago, Troy Tempest said:

ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

Do you mean SSSSSSSSSSSSSS (for South ?? ???? )

[Crossy]

37 minutes ago, Muhendis said:

I was once a contractor but I never imagined myself being normally closed

 

MS Word insists on correcting "earthing" to "earthling" which does make some electrical specs. interesting reading ???? 

[Dazinoz]

29 minutes ago, JBChiangRai said:

A Priest, a vicar and a rabbit went into a bar, the barman asked the rabbit what he wanted to drink.  The rabbit replied “I don’t know, I’m only here because of autocorrect “

I knew an electrician once who was charged with assault and battery so they put him in a dry cell. It was a current crime but they sent him ohm.

[Muhendis]

Just now, Dazinoz said:

I knew an electrician once who was charged with assault and battery so they put him in a dry cell. It was a current crime but they sent him ohm.

Where's the groan emoji?

[MJCM]

This thread Got me thinking (which is a good thing I hope) about the orientation

 

I am getting a 5kW system, (suppose) with 16 Panels (each panel 330w) but suppose I am getting an extra 6 (also 330w) panels and they are lined up like this.

 

I put 3 Panels facing EAST

I put 16 Panels facing South (for maxi charge)

I put 3 panels facing West

 

Does this mean I have to get a BIGGER Inverter as well (> 5kW ???). ?

Any advantage to this ? (Disadvantage I know they panels are expensive and this is a +/- 30k extra investment)

 

Place for the panels I have in abundance, I could place 50 panels there.

 

TiA

 

[Muhendis]

I have seen a solar panel array with a few added panels facing east and west angled to catch the early morning and late afternoon sun. This in addition to the main array facing south. The east and west panels are a bit useless most of the day but maybe that arrangement will allow for good battery charging early and late so less main power needed the rest of the day.

[jaideedave]

19 hours ago, FritsSikkink said:

They should face the sun.

What about at night..?

[Muhendis]

1 minute ago, jaideedave said:

What about at night..?

Invert them to comply.