PEA and Solar how low can you go?

[MJCM]

At the moment we are using a Grid-Tied inverter with 3 panels but we are preparing to get "real" Solar (Hybrid Inverter with 10 Panels).

 

We normally use on average around 300 Units per month (measured over a period of just over 2 years),  but this month and last month (since we started with the GTI) our bill is already reaching very low heights (for our standards), last month it was 191 Units and this month the prediction is 162 Units.

(Ps: This lowering of our bill is NOT 100% because of the GTI another contributing factor is the weather, lots of rains and thus no watering of the garden)

 

So a question for the guys with "unofficial" Solar installs that feed back into the grid

 

How low did your PEA meter go after you installed Solar and what was your normal (before Solar) usage?

[Crossy]

We "weened" PEA on to lower meter readings over some time (actually by gradually installing more solar). Whether I really needed to I don't know, but a sudden reduction in usage could raise eyebrows. 

 

My records don't go back to before we had solar but our bills were regularly 5-6k Baht per month. Now we are around 1k or less.

 

The critical point (as informed by the PEA supervisor) is not to let your meter reader actually see the meter running backwards.

[MJCM]

6 minutes ago, Crossy said:

The critical point (as informed by the PEA supervisor) is not to let your meter reader actually see the meter running backwards.

Thx,

 

yes and don't go into negative territory, I mean with that, that the Recent reading of the units on your new bill is higher then the Previous reading (or try to keep it at Zero as @Bandersnatch is doing (most of the time ???? )

Edited October 1, 2022 by MJCM

[KhunLA]

Rental was low of 450 units, high of 700.  Moved into house and solar installed shortly after.

 

First full bill with solar, 28 units and can't feed back to grid due to new digital meter.

 

House at Udon Thani before moving to PKK were 2500-5000 baht.

Edited October 1, 2022 by KhunLA

[MJCM]

thx

 

2 minutes ago, KhunLA said:

First full bill with solar, 28 units and can't feed back to grid due to new digital meter.

When we get our "real" solar installed, I will leave export to the grid off for the first month so the Solar (we will not install an ESS at first) will only contribute to Day time usage. I really am curious what that will do to our bill.

 

If the bill is too high, I will then turn export ON ????

 

Our current setup (only 3 panels) already contributes +/- 2 units a day (when it's not raining).

[Crossy]

Here you can see our PEA weening process.

 

Overall usage is the red graph, peaks in May 2020 and May 2021 when it was hot and I was WFH (with the A/C blasting), nothing this year as I wasn't.

 

Green line is PEA usage, steady downwards trend. The difference between May 2020 (1,704 kWh) and May 2022 (140 kWh) doesn't seem to have raised any flags. Yet.

 

Our total daily usage seems to have stabilised at around 30-35kWh so we could add a bit more solar (I have space for 6 more panels).

 

[MJCM]

nice and clear overview @Crossy
 

Looking at this I don’t think I have to worry with our 140 units lower then average ????

 

And just in case the PEA changes our meter I will just try to hurry the install of the ESS

[007 RED]

Prior to installing our small scale GT solar system (360 days ago), we were purchasing around 280 - 300 units per month.  The aim of the system was to reduce our bills by 75% thus ensuring that we never got into negative meter readings. 

 

Like @Crossy,  I weened the readings down incrementally for the first couple of months by activating the 'NO EXPORT' facility for short periods of time during the month to ensure that some 'bright spark' at our local PEA didn't notice a sudden drop in consumption,

 

Since the system has been operational our bills have been on average around 90 units per month, which is slightly less than I'd hoped for, or approximately 68% solar and 32% purchase.

 

Foot Note:

In hindsight I'm not to sure if a sudden drop in meter readings will raise any 'alarm bells' with the PEA.  Prior to Covid restrictions being introduced 2 years ago, one of my neighbors (husband, wife and daughter) were living at home and commuting into BKK on a daily basis for work/university.  When the travel restrictions were implemented they rented an apartment in BKK and returned home at the weekends.  The whole family love their ACs which are on day and night, so their bills prior to Covid would have been substantial and there would have been a considerable drop in the number of units purchased each month once they started living in BKK.  I've just spoken to the wife and she advised that they have not been contacted by the local PEA.  So, no problem ????... hopefully.

Edited October 1, 2022 by 007 RED
typo

[MJCM]

You are right @007 RED

 

When we lived in our old house we had avg readings of well over 300 units, but when we moved  to our new house, the usage dropped to around 40 units because of fridge running, BIL sleeping there sometimes etc  and sometimes much higher when family from BKK were staying there. 
 

And we had never any questions or enquiries from the PEA as to why.

 

i will go ahead with my plan and leave the export OFF the 1st month after install and see what that does.

[sidgy]

As above. Within a couple of months, our usage from grid was down 60%, no concerns ever raised.

When home, i always ensure we are using more then producing on meter reading day, when i'm away, i am fairly confident the wife is not so "methodical"

Our bill is also creeping up as the wife is a lot more carefree with usage  "as its free" haha

[Crossy]

1 hour ago, sidgy said:

Our bill is also creeping up as the wife is a lot more carefree with usage  "as its free" haha

 

Yours too??

 

There's a new place going up opposite us, I will be watching closely what kind of meter they get.

[MJCM]

6 minutes ago, Crossy said:

There's a new place going up opposite us, I will be watching closely what kind of meter they get.

Maybe open another thread about it like the "brick" thread and it will another one full of suspense ????

Edited October 1, 2022 by MJCM

[MJCM]

Another question, this time about NO-Export

 

Suppose you have NO-Export turned on, and your house is only using let's say 300W, but the Panels are producing (again let's say) 1500W.

 

Where does those approx 1200W (difference between usage and producing) go instead of going into the grid?

[KhunLA]

4 minutes ago, MJCM said:

Another question, this time about NO-Export

 

Suppose you have NO-Export turned on, and your house is only using let's say 300W, but the Panels are producing (again let's say) 1500W.

 

Where does those approx 1200W (difference between usage and producing) go instead of going into the grid?

The inverter will handle that, and simply use what is needed.  Our's produces and uses all, until battery is topped up, then the produced/consumed is about the same.  On the graph, it's actually hard to see the produced over consumed, once battery is topped up.  Here's today's:

The extra over produced/blue, I'm guessing is what the inverter itself is using, and that's about 40-80w per hour, depending on workload of inverter.

 

TBH ... I haven't a clue where it goes, if it goes anywhere ????

[Crossy]

40 minutes ago, KhunLA said:

TBH ... I haven't a clue where it goes, if it goes anywhere ????

 

It doesn't go anywhere it just never gets generated, if anything the energy just goes into warming up the panels as it would if they were just the roof.

[007 RED]

1 hour ago, MJCM said:

Another question, this time about NO-Export

 

Suppose you have NO-Export turned on, and your house is only using let's say 300W, but the Panels are producing (again let's say) 1500W.

 

Where does those approx 1200W (difference between usage and producing) go instead of going into the grid?

As @Crossy has indicated above, it really never gets generated.  My inverter (Sofar 2.2kW GTI) can be set to export from zero to 100%.  I have it set to zero and activate 'NO EXPORT' a couple of days prior to meter reader visiting.  During the 'NO EXPORT' period the Current Transformer (CT) which is clamped over the live wire between the consumer box in the house and the meter on the pole outside is sending feedback to the inverter as to how much power we are using in the house.  The inverter then adjust itself to only produce enough power such that no power is exported thus making the meter spin backwards.

 

Take a look at the graph below produced from the system's monitoring facility the day before the meter reader came.  The system was in 'NO EXPORT' mode, and shows power production (blue) against power consumption (red). 

 

You will notice that at times the consumption 'hits the roof' and the system tries to match that demand but fails abysmally because there was not enough sunshine hitting the photocells.   You will also see that at other times the power production equals the power consumption even when there was good sunshine (mid-day) thus illustrating that power production is matching power consumption.

[MJCM]

Another 11 days to go but we will (estimate) have only used around 169 units in total when the meter reader comes. Previous month we used 191 units so 169 is another 22 units below that

 

This is a screenshot of our last 4 readouts

 

 

[KhunLA]

One more bill to go, and PEA's calculator tell me ฿58

 

Then the wait to see how many months of -0- units used, it takes for them to replace the meter ... ????

Edited October 5, 2022 by KhunLA

[MJCM]

6 hours ago, KhunLA said:

Then the wait to see how many months of -0- units used, it takes for them to replace the meter ... ????

No replacing I guess a Software Update

 

which will do the following

 

Quote

 

if PEAMeter from KhunLa and Unit IS NOT increasing then

  increase anyway

end if

 

????

Edited October 5, 2022 by MJCM

[MJCM]

PEA bill for Sept - Oct just arrived.

 

Instead of the expected 169 Units used, we ONLY used 155 units (which is our lowest BILL ever) thus another 36 units less then the previous month in which we used 191 units.

 

Also first bill ever (for us) under 600 THB, it's even lower then the month were we got our permanent meter and we weren't even living here yet.

 

Next month we will be trying to get a bill under 500 THB ????

 

[Crossy]

Don't forget you should have received the FT discount of nearly 1 Baht per kWh for under 300 kWh ???? 

 

[MJCM]

13 minutes ago, Crossy said:

Don't forget you should have received the FT discount of nearly 1 Baht per kWh for under 300 kWh ???? 

 

 

144.82 original Ft charge discount of 142.66 THB = 2.16 THB Ft charge. Without it the bill would be over 700 THB.

Edited October 16, 2022 by MJCM

[digbeth]

Does the 'digital' meter has feature to prevent export? newer TOU meter seem to be all digital now

[Crossy]

18 minutes ago, digbeth said:

Does the 'digital' meter has feature to prevent export? newer TOU meter seem to be all digital now

 

Generally they don't go backwards on export unless programmed to (if you join the FiT scheme).

 

There are reports of some that actually log exported energy as chargeable, so you actually pay to export, not something you want to do of course.

[MJCM]

Another 13 days before the meter reader comes and we turned off our GTI as the BILL will be really getting low. We are now, if we leave the GTI running (prediction) going into low 100 units used, 87 to be precise that almost 44% lower then the previous month

 

Edited November 2, 2022 by MJCM
SpElLiNg

[JAS21]

Our system ... https://aseannow.com/topic/1274669-another-diy-solar-project/#elControls_17662832_menu ... has been running for about one month now.

 

The meter man comes every 16th of the month. Since 16th October we have been running NO EXPORT. Since then we have generated 216kWh and imported from the grid 48kWh. So in total have used so far this month 264kWh. Expect this month our usage to be IRO 80-90kWh.  

 

We have charged the car up a few times but most of the usage has been air con which was the reason for putting solar in anyway.

 

We have had quite a cool house, so much so that the mosquitoes have had trouble walking, nevermind flying. Cooling the house during the day has resulted in using less air con in the evening.

 

[MJCM]

2 hours ago, JAS21 said:

Expect this month our usage to be IRO 80-90kWh.  

What was your previous months usage from the PEA/MEA, we in 4 months dropped from 262 units to (prediction) 87 units (and could have gone even lower

[JAS21]

166-246-390-387-448-325 ... but don't read a lot into that because we had away periods in most of those months 

[MJCM]

On 10/16/2022 at 1:36 PM, MJCM said:

Next month we will be trying to get a bill under 500 THB ????

 

Last month I said this, today our bill came, and we used 106 Units for a total price of 410.91 THB (inclu the Ft Discount)

 

Previous month we used 155 units so this month we used another 49 units less.

[Encid]

So... planning for 60 units next month?