Solar - 8kW Hybrid Inverter w/10kWh (upgraded to 20kWh in Sept. 2022) ESS/battery (not DIY)

[Crossy]

11 hours ago, MJCM said:

I would love to have all our lights on (and aircon working) when there is a power failure and everywhere else is in darkness (how cruel that may sound).

 

There are negatives to being the only place in the village with power:-

• The locals will flock to see their "friend" for a chat
• They will use your WiFi (for the kid's homework of course)
• They will watch your TV
• They will eat your food
• And worse! They will drink your beer
• And even worse! They won't go home even after the juice comes back on

Actually, a by-product of having a decent UPS backup is that the grid reliability will improve significantly (like washing the car when the garden needs rain guarantees a downpour).

 

 

[MJCM]

45 minutes ago, Crossy said:

Actually, a by-product of having a decent UPS backup is that the grid reliability will improve significantly (like washing the car when the garden needs rain guarantees a downpour).

555555555555555

 

With us it is guaranteed rain after mowing the lawn

[JBChiangRai]

15 hours ago, Crossy said:

 

Thing is, what happens when your "3kW" system starts blasting 9kW into the grid?

 

The authorities here are not totally stupid, despite appearances sometimes.

I would be surprised if they keep those kind of records.

[MJCM]

14 minutes ago, JBChiangRai said:

I would be surprised if they keep those kind of records.

I tend to agree but it is one thing you paying for the Electricity they produce and another thing for MONEY they have to PAY you for Electricity you produce.

 

So IMHO more scrutiny on the last bit (because they don't like to pay, see how difficult it is to apply for this net metering)

[JBChiangRai]

I just spin my meter back like most people, but I did hear that new meters fitted now are electronic.

 

I have 54 panels, 3 x 6kw grid-tied inverters, 3 x 5.5kw hybrid inverters (used as whole house UPS without solar panels), 28.8KwHr's of LiFePo4 batteries.

[MJCM]

10 minutes ago, JBChiangRai said:

I just spin my meter back like most people, but I did hear that new meters fitted now are electronic.

Yes I heard so as well and there is even talk that the electronic meter also charges you for electricity that you put into the grid. (@Crossy will know more about that)

 

We are fortunately that we still have a Meter that spins backwards but I am monitoring it so that we don't go to low. (Last month 106 units, this month prediction 71 units (if we keep letting the GTI's to export))

[JBChiangRai]

My lowest reading was 2 units ????

 

I fitted Solar when I built the house so there is no history for their software to notice a change of usage habit.

 

Actually, they do know but don't care here in Chiang Rai.  We had a visit from them one night when they got fed up of shuffling fuses at the transformer because we were blowing them one after another.  They told me I was using 56 amps when they put a clamp over my meter cable.

 

There used to be an estimated 50 Air Conditioning units on one phase of their 100amp transformer.  There are 6 large houses here on this development that were on one phase, they have now moved 2 houses onto each of the 3 phases which has also prevented me exporting all my power too.

[Crossy]

4 hours ago, JBChiangRai said:

I would be surprised if they keep those kind of records.

 

I would be most surprised if they do NOT keep such records.

 

At the simplest level they would know how much you exported each month. I can check my monthly consumption back to March 2021 on the normal PEA App, why would something similar not exist for those exporting? Also, the electronic meters are quite capable of recording the peak consumption / export.

 

Whether they actually care or take any action is of course debatable.

[JBChiangRai]

48 minutes ago, Crossy said:

 

I would be most surprised if they do NOT keep such records.

 

At the simplest level they would know how much you exported each month. I can check my monthly consumption back to March 2021 on the normal PEA App, why would something similar not exist for those exporting? Also, the electronic meters are quite capable of recording the peak consumption / export.

 

Whether they actually care or take any action is of course debatable.

I was being imprecise, of course they keep the records, whether or not they have Business Intelligence software or even Human Eyes to check that you are exporting more than your 3Kw authorised system, I strongly doubt.  

[MJCM]

21 hours ago, JBChiangRai said:

My lowest reading was 2 units ????

I am getting there. Highest reading this year was 348 Units and for this month the prediction is 71 units and that is with a VERY simple 2 GTI system with only 6 Panels (and I must say also with some other changes, like removing some UPS's which were faulty etc etc). Our install to be (hopefully next month) is a 5kW GTI with 10 Panels and that will push it even further down.

[KhunLA]

Ah solar ... planning is everything, with an eye on the weather ... ????

 

If wanting to stay as 'off grid' as much as possible.  Especially if having a digital meter/no rolling back, not that it matters in the short term, with thunderstorms in the forecast.

 

3 days of krap forecast, probably not accurate, as rain was forecast today, and sun was out ... so I topped up the EV using  few kWs of ESS ???? before the pending doom starts tomorrow/4 Dec.  Think we went into the night at about 85%.  And then it came ... 3 full days of thunderstorms ????

 

Luckily the sun did pop through some thin clouds, just a bit, , on all 3 days, or we would have gone below 50% on the ESSs, which I prefer not to.

 

We barely produced enough to meet consumption.   As me, wife & dog huddled around the 1 fan in total darkness, and cooking on the gas stove.

 

"Good GOD woman, shut the frig" ... and  ... "Sniffy ... No, drink tap water out of your bowl, no fresh cold water today" ????

 

"Honey can we .... "

"NO, leave the grid off"

 

 

 

 

[KhunLA]

I guess I need to wait till late Feb, Mar & April before getting a good ROI.   Even charging the car most of yesterday, and I couldn't break the 40kW ceiling ????

 

[KhunLA]

2022 ... can't seem to break 600kW for the month

 

Previous Months

 

[motdaeng]

7 hours ago, KhunLA said:

2022 ... can't seem to break 600kW for the month

can't seem to break 600kW consumtion (?)  for the month 

 

can you estimate your real kw number for the produktion?
it would be also nice nice to see, how much your newly built

8 kwp solar-system effectively produces per month / year ...

[KhunLA]

57 minutes ago, motdaeng said:

can't seem to break 600kW consumtion (?)  for the month 

 

can you estimate your real kw number for the produktion?
it would be also nice nice to see, how much your newly built

8 kwp solar-system effectively produces per month / year ...

Not sure I understand the questions.

 

Most everything produced is used, why numbers are so close.  Only time they were noticeably different, was when feeding the grid a few days, and anywhere from 5-15kW a day produced, went out of the house to the grid.  That only a few days, the first few weeks having, till new digital meter replaced spinning meter.

 

I notice the inverter itself, uses from 30-80w an hour, so fairly minimal.

From memory, think the promo info on panels & inverter were high 80 to high 90% efficiency, but TBH, haven't a clue how I could test or verify that info. 

 

Especially since with no export, only what's used passes through the inverter.  18 X 540w panels should have potential to produce 9.72kW an hour at max, and promo states inverter will handle 10kW in, and 8.8kW out.  With full on sun, and charging the ESSs, production rarely touched 8kW, and only once was knocking on 9kW.

 

I based the size of the system on our rental use, of 1 small, old AC in the bedroom, and we used 600-700kW/PEA units a month.   So actually expected to use 700-1000kW at this house, running 2 larger AC units a lot longer.   The quality build & inverter ACs certainly made a difference, and much more than expected.  Along with more electric appliance use in the kitchen.  Surprised the ACs run as efficient as they do.

 

Part of the low usage also can be attributed to the weather.  Longer rainy season, more overcast skies, and nice temps since installed.  Feb, Mar, Apr may be much different, and a better test of both, house & ACs.   Neither stressed since installed.

 

Our most produced day, still 18Aug, but 15kW of that went to the grid, along with knocking on 9kW being produced.  But since partly clouding, as shown by peaks & valleys, hard to tell if full on sun would have maxed out production potential.   Very happy with 8kW+, as 6 hr day or full on sunshine, and close to 50kW potential, which we'll never use.:

I doubt if a 5kW system would have been enough, especially since having a digital meter, and the EV. 

 

8kW system, at present seems to be overkill, and we can't use it's potential.  A good thing, as longevity of components should be extended, since not stressed.

 

Adding the 2nd ESS made a huge difference for no stress overnight use during rainy season.  Some days producing < 10kW, and using 5kW overnight.  So 20kW ESS vs 10kW means we don't have to pay attention at all.

 

A couple times, I turned the grid on, when just having a 10kW ESS, so not to go below 35% reserve.   Now I plug in the EV, at 0600 before sunrise, knowing with have 4-6kW to play with, before hitting 50% of ESSs, and before producing enough to cover the house load (<1kW) & EV (2.3kW).  Usually by 0830 hrs, production matches consumption.  You can tell by the shaded red, until the blue is visible, thus excess going to batteries.  Once topped up, it simply produces, accepts from the panels what is needed.

 

 

[motdaeng]

@KhunLA

 

thanks for the detailed explanation, i appreciate it.

 

it seems you don't need to worry about your system,
even if you use a lot more electricity in the future, well done!
 

[KhunLA]

Monthly breakdown for the year, only 5 months.  For those curious, but too lazy to start at page 1.  Note the title of thread is wrong, as '8kW hybrid' now having 20kW of ESS.

 

Second 10kW ESS was added early Sept, as late Aug, they replaced our temp meter, with a digital, so no feeding the grid.  Easy to tell which days (8) that we did feed the grid in August, along with heavier AC use.  Very conservative use/consumption, since only 10kW ESS during Aug, and first 2 weeks of Sept.

 

 

 

Picked up the BEV on 30 Oct, so easy to tell which days we were charging the car, along with which days we were out all day exploring locally, since no petrol cost to do so.

 

 

Happy New Year

Have a Safe & Healthy 2023

[Crossy]

@KhunLA - want me to update the topic title?

[KhunLA]

6 minutes ago, Crossy said:

@KhunLA - want me to update the topic title?

Please ... Thank You

[Crossy]

5 minutes ago, KhunLA said:

Please ... Thank You

 

Done ???? 

[Crossy]

1 hour ago, KhunLA said:

Picked up the BEV on 30 Oct,

 

Which BEV do you have? Thoughts?

[KhunLA]

1 hour ago, Crossy said:

 

Which BEV do you have? Thoughts?

MG ZS ... only 2 months, but really like it.  Had the ICE version just prior for 2 years/38k kms.  So no real surprises, nicer fit & finish, along with performance.  Nice upgrade all around.

[KhunLA]

So what's a semi-normal 'Solar' day like ?

 

Today, far from peak conditions, which would be sunny blue skies.  Instead we have some thin overcast, and AQI @ 78, but, sunshine still coming through and enough to cast strong, dark shadows.

 

Short vid, producing shy of 7kw, the EV is plugged in (2.3kW), and two inverter ACs running, set @ 27°, which I just raised to 28°, as the bedroom was a bit chilly, was 23° ish, now 25°.  ACs (13 & 24BTUs) conditioning about 105 m².

 

Producing ATM, 6.8 ish kw

EV & house load @ 3.5 ish kW

ESSs taking 3.25 ish kW

inverter using the rest, and minimal

Sun is still a little SE, as shadow is NW, so not prime exposure yet, especially on W panels. This about 1 hr ago.

[Peciacake]

Many thanks for your posts on this topic Khun LA.  Very much appreciate the information you've provided.  Good to see the results from your system - gives me confidence to go in a similar direction with the system I'm planning.

[KhunLA]

Here's breakdown of hours of sun exposure, for 'our' system, NOT having panels facing East.

 

Having 9 panels facing S & W, slight pitched roof, so good exposure on those panels.   Sun coming up a bit SE, so S panels getting better exposure, than say June/July, when rising sun more due E or slightly NE.

 

Panels start producing just after 0700, minimal, but producing.   EV was plugged in prior, so didn't produce more than consumption, until 0920.  Without the EV (2.3kWh), production would have been more than enough to meet consumption after 0800.

 

Very light overcast, but no clouds, as no peaks & valleys in the blue.  If no overcast, then would produce a bit more.  See it maxed at <7kW.  When clearer skies & sunnier, got near 9kW. 

 

At 11:20, it was producing 2X consumption, shy of 7kW vs 3.5 kW.  At 1200, the EV was about done, and 1230, batteries topped up.  Simply imported what was needed afterwards.

 

Stopped producing enough for consumption at about 1730.  So almost 14 hrs overnight, 1730-0730 today, the house runs off the ESSs.  

 

[KhunLA]

Today, and no EV charging, and ESSs topped up at about 0940 hrs

 

 

 

[KhunLA]

Stop producing, last bit to ESSs @ 17:23

Start producing, we bit to ESSs @ 07:13

94% - 70% = 24% = 4.8kWh overnight, 14 hrs

 

 

 

 

[Muhendis]

I really do like that display.

It's a simple, no messing about indication of what is happening overall.

[KhunLA]

Finally broke that 600kWh ceiling for the month.   Though it did take a few long day trips (4 (100-200kms), and 1 overnight (270kms) with the EV to do.  

[KhunLA]

Breaking another record, most produced/consumed in 1 day, without export.

 

Exceeded 41 before, but were exporting about 15kWh to grid.   Yesterday, 41 ish kWh, with the MG ZS using 20 of those kWh.   ZS will use another 13kWh today when finished topping up.

 

And we didn't even turn on the ACs for the house till noon ????