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My Issan 10kw on grid solar project fully installed by contractors 337,500bht


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The no-export controller for inverters with a CT is here 

I'm working on a software update so it can be automatically configured to your WiFi meaning I can program an ESP8266 for you so no need for messing about with programmers.

 

EDIT Attempt 1 at the auto-config is now in the Solar Carport thread 

https://aseannow.com/topic/1120934-how-about-a-solar-car-port-on-a-budget/?do=findComment&comment=16961880

Enjoy.

 

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9 hours ago, 007 RED said:

I’ve just installed a small solar system on my carport roof comprising 4 x 415w panels plus a Sofar 2kWh grid tied inverter.  Approximate total cost 26K (THB).

 

My wife and I are not big electrical users. Our average monthly usage (over the past year) has been about 650 units/month, so my intention from the onset has been to create a system that will reduce our bills by 50%.  I appreciate that ROI over the short term (a couple of years) will not be that great, but I was taking a longer term view where reliability was paramount due to our age.

 

My electrical knowledge/experience was somewhat ‘rusty’ (Ohms Law at polytechnic 50 years

ago) but following the basic common sense safety rules (switch things off and testing before ‘playing’) enabled me to DIY the installation with some great support from members of this forum.  The biggest concern on my part was getting up onto the sloping carport roof, which is 4 meters above ground level at its lowest point, to install the panels.

 

From the initial research that I did, I think that you will find that the ‘cheaper’ grid tied inverters do not have any capability of controlling the export of any surplus power generated by the system, other than turning the inverter off completely.   Some of the more expensive grid tied inverters have a facility to allow a Current Transformer (CT) to be connected to the positive line from the power pole to the house.  The CT is then used by the inverter to measure the flow of current which allows the inverter to determine if, and how much, power is being exported.

 

The Sofar grid tied inverter allows you to set the maximum amount of power you want the system to export e.g. Zero or 100%.  What the inverter cannot do is determine what days of the month it will allow the system to export, or not export.  This has to be done by either physically, or electronically, breaking the connection between the inverter and the CT.  Strange as it may seem, with the CT connected to the inverter (and the inverter set to zero export) there is no export, however, with no connection between the CT and inverter the inverter allows the system to export any surplus power to the grid.

 

My initial Export Controller is a simple on/off (light) switch located in a water/insect proof housing between the CT and inverter.  I have the calendar on my mobile set to remind me to physically switch the Export Controller off a day before that meter reader is normally due to come.  I leave the Export Controller off for 3 consecutive days just in case he comes on a different day.  I’m currently installing Crossy’s electronic Export Controller which will allow the system to be controlled automatically or via my computer/mobile.  A wonderful little self-made addition.

 

I found that installing my small grid tied system was not that difficult and only required some very basic knowledge, skills and tools.  If I can do it at 75, I sure that most younger folk can make a better job of it than me.

 

Go for it and good luck.

 

PS... My little system is currently churning out about 5kWh per day despite the recent heavy rain and clouds.

Thanks for the very interesting and inspiring post. I’m an enthusiastic DIY’er and willing to tackle most jobs but must admit to being apprehensive about electrics due to potentially severe and possibly even fatal consequences. There is also the small issue that I live in a double storey house whereby my lowest roof line is about 8 metres up. I do have a carport roof that’s only about 3 metres high so that might be a possibility….

 

For a similar 2 kwP system from a commercial installer, the price would be around Thb 100k. How can they justify such a huge difference in price? Sure, they have to pay labour, business operating expenses and profits but still…

 

Finally, I have a few questions if you don’t mind. Is it difficult to source for all the required materials such as cables, connectors, circuit breakers etc? Did you custom make the mountings for the solar panels or just simply purchase ready made ones? Apart from the panels and an inverter, I would also need a CT and an export controller? (although if I’m not mistaken, Crosby mentioned that some inverters come with a built in export disable switch/function). And finally, connecting to the grid. Is this a simple matter of literally plugging in a plug to an existing socket or having to tinker with the main fuse board?

 

Cheers

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10 hours ago, KhunLA said:

A question on PEA 'buyback' of excess.  Do they actually pay in baht if sending more than used.  Going solar hopefully before end of year, when house done, and hope I over estimated to system.  To the point of not needing any PEA service and bill will be the 41 baht hook up charge.

 

If sending PEA 100 or 200 units a month would they pay cash, or simply deduct from PEA use only, and if no use, obviously not deduct but can any cash payment be expected, or just a very silent, non existent thanks.

If you don’t intend to be drawing any power from the grid, I would assume that you are going for a hybrid solution with lots of batteries? If so, I wonder if you would actually have any excess to export to PEA as surely the surplus would be required to charge your batteries instead?

 

P/s: I’m an absolute noob in this so trying to learn as much as possible 

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10 hours ago, KhunLA said:

A question on PEA 'buyback' of excess.  Do they actually pay in baht if sending more than used. 

KhunLA going from what my Luv Machine was told by Nang Rong PEA (Burriram) there are a few options. You can get a transfer into a bank each month for any excess. Save the monthly excess and claim at a later date (why would you do this!!). Save the excess and take it off future readings when the consumption is higher than production. Note.. I have not seen this in writing anywhere just from the horses mouth..

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1 hour ago, Gweiloman said:

Finally, I have a few questions if you don’t mind. Is it difficult to source for all the required materials such as cables, connectors, circuit breakers etc? Did you custom make the mountings for the solar panels or just simply purchase ready made ones? Apart from the panels and an inverter, I would also need a CT and an export controller? (although if I’m not mistaken, Crosby mentioned that some inverters come with a built in export disable switch/function). And finally, connecting to the grid. Is this a simple matter of literally plugging in a plug to an existing socket or having to tinker with the main fuse board?

It is not difficult to source all the materials. You can get through the usual Lazada etc on-line stores if you know what you need. I have not purchased anything from these guys in the link below as at the 11th hour I decided to stick with contractors. (I'm talking about my up and coming Battery installation). Sometimes you get sick and tired of searching for stuff. This site has all the bells and whistles solar related and the sales guys very helpful with info. Note they like the phone App Line to communicate and not email.. Just the Thai way.. Quick to respond. The prices for batteries beat everywhere else I looked (Huawei). They sell complete kits. Thai based company.

 

https://www.godungfaifaa.com/

 

Pluging into an existing socket can be done ...BUT.... that is really scary stuff...really scary!! Make sure the main breaker is off to the grid and have the local fire truck number saved in the phone... It's best to tinker with the main fuse board with an inverter that will not export during a blackout. Like i have said before "I know enough about electricity to know I know very little"..Silent killer..

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1 hour ago, Gweiloman said:

If so, I wonder if you would actually have any excess to export to PEA as surely the surplus would be required to charge your batteries instead?

Good question.. The batteries can only charge at a certain rate ie consume so much energy while charging. So if the Solar is putting out more than the batteries can eat while charging the excess goes back into the grid.... That's what I am hoping for anyway when my batteries show up!!!!

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On 2/24/2021 at 4:51 AM, tgw said:

 

it's much more complicated than that, there are days with insufficient production because of cloudy weather where power has to be bought from the grid, malfunctions, battery weardown, etc.

 

Does a typical system not come with some sort of emergency storage?

 

Am I right in saying on average do you pay for for electricity from PEA then they buy it from you? never looked at my bills 5555

 

Thank you so much for everyone contributing to this thread. A fountain of knowledge and great advice for my plans.

 

Krap Phom ????

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7 hours ago, bangkokbonecollector said:

Does a typical system not come with some sort of emergency storage?

 

Generally no, the cheapest systems are grid-tied, see the pinned thread on inverter types https://aseannow.com/topic/1228023-whats-all-this-on-grid-off-grid-hybrid-stuff-all-about-solar-systems-demystified/

 

 

If considering going DIY this thread is worth a look.

 

 

 

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On 2/24/2021 at 12:38 AM, mistral53 said:

I have a very similar system, albeit having 3 phases, I am able to use a single Huawei 12 Kw inverter (leaves some head room for expansion is I decide to do so)

I want to make some comments to your interpretation of the above graph: your consumption is massive at 87 Kwh per day, for 23 PV panels your production is off the charts at over 60 Kwh - nevertheless, it leaves you with a 17 Kwh deficit. Also, the graph does not make sense as your energy usage is almost perfectly tracking the output - I can see every load I add, e.g. pool, AC1, 2, 3, 4, water heater, car charging etc - a totally jagged 'curve'. If you are interested I can share my yield/usage graph to show what I mean. Not intended to hi-jack your thread, just adding some context.

Out of interest, how old is your system and was it a simalar cost to install?

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12 hours ago, Thaifish said:

 

 

Pluging into an existing socket can be done ...BUT.... that is really scary stuff...really scary!! Make sure the main breaker is off to the grid and have the local fire truck number saved in the phone... It's best to tinker with the main fuse board with an inverter that will not export during a blackout. Like i have said before "I know enough about electricity to know I know very little"..Silent killer..

If I recall correctly, Crossy mentioned in another thread that it is quite safe to plug into an existing socket if using up to a 2Kw inverter. I would imagine that the inverter would have a built-in automatic cutoff to the grid when it is not getting any power from the socket/grid. 
 

If so, then getting 2 identical inverters (with the corresponding number of panels) would be the simplest way to go. I can get up to 4kwP easily that way. 
 

Waiting for 007 Red to start his thread ????

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12 hours ago, sezze said:

Like the post from Crossy , but there are plenty of options , all with a price point . A grid tie inverter with limited feedback to grid( or none) and battery connection does exist ,  but many aren't cheap . I think 1 of the cheapest around is the Sorotec Revo 2 . This is very useful if you want the feed in grid and keep the battery as a backup in case of blackouts . For the same amount you can double out your system , 1 grid tie inverter , taking care of daily needs and putting in the grid , and a standard hybrid off grid which does take care when power is out . 3th and most expensive option , and most of the time the best option is having all that in 1 single box . Unfortunate they do not come cheap , there is no reason why they would be more expensive then the others , but since i do not make them , that's just the way it is . This 1 can do all , meaning grid tie if you want to , put in net what you want , and inject even from battery when your solar isn't enough.

Everything has got it's pricepoint , it all isn't extremely expensive , but neither is it cheap , and requires a initial investment . It will pay back itself after a while , but putting a system together needs planning , since you are looking at payback of at least several years (2.5 to ???? .

Really good advice so thank you very much for your taking the time. Everyone on this thread have really done a great job of explaining individual systems and issues.

 

I can definitely see it is expensive and without sounding too much of a snob, I would rather get European or Japanese tech and I presume that would cost even more! We have a few years until we start to build, so hopefully by that time things might have become slightly cheaper and streamlined.

 

Thanks again to all!

 

Bone

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Not to mention , but many work on main lines is done under "life" or "hot" conditions . Meaning , the grid is still on , and he is working when there is power on it . This also means he got protection gear on ( in Thailand prob Thai style ) and is ready for possible hazard .

In the cases where he expects the power to be really off , he will check this a few times .

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Most problems will prob occur indeed with a transfer switch and generator . When the grid is off , generator is on , and thx to faulty wiring/installation/transfer switch , putting it back in the empty grid is possible.  I highly doubt it is possible when the grid is on , since it would cause a massive short circuit thx to the generator not in sync with the grid .

All grid ties like said do have anti-islanding features and while it might be possible in theory when having several GTI in house to have a islanding happening , chances on that happening are very unlikely ( has been tested before , and even then , they still go out within milliseconds ) .

Off grid hybrids , they simply cannot put back in grid , while they have a incoming wire from grid , they will not send anything over to that side , since it isnt connected . Putting IN/OUT wrong , might in theory send back in grid , but then we get the same problem as with the generator , not sync'd -> short circuit .

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  • 4 weeks later...

Christmas aint come yet. Still no Smart Meter and still no Batteries!! On the positive side had two visits from Korat PEA regarding installation of the Meter. For the life of me I'm not sure what they where actually doing or the real purpose of the visit. The first visit as explained by the Luv Machine who also had no idea was the Thai Energy Regulatory Commision who are the PEA Police in lose translation!! The task was to ensure that Tax had been paid on the installation. The thing is they never inspected anything. No receipts or paperwork just had a friendly chat got the Luv Machine to sign a document saying we had been inspected and everything was Hunky Dorey. Chock Dee and off 3 men went on their 1.5hrs return trip back to Korat!!!

The next Guy to turn up a week later brought a Multi Meter and actually opened up the Solar fuse box's and took a few readings. Got the Luv Machine to put her Monica Lewinsky on another piece of paper saying we had been inspected and everything was Hunky Dorey.

At least PEA know we are alive.

Have been waiting on the Batteries for 6 weeks now. No need to say anything more!!

 

Produced 1.295Mwh for the month. Production seems fairly constant with just over 1Mwh each month since installation. We had plenty of Sun this month.  The panels orientation are pointing more directly at the sun but struggling to put out 8kw whereas during the wet they where pumping 9.5 to 10kw but less direct orientation and obviously plenty of cloud/rain. Gave PEA 959kwh free (2100Bht) and also paid 1,500Bht Fai Bin... 74% of production went to PEA free... BREATH IN THE GOOD AIR BREATH OUT THE BAD!!!!!!!!! No blackouts for the month.

 

Monthly Solar Yeild December 21.png

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  • 1 month later...

The winter Solstice came and went and so did Santa. Managed to break another record with production 1.42Mwh. Lots of Sun but short days and the Inverters struggling to pump out more than 8Kw around midday. Somehow the Inverters changed from Export to Non Export during the last couple of days of November and the first couple of days of December before I picked it up.. Me thinks Big Brother in Bangkok has been playing with settings remotely?? So averaged 49Kwh per/day (using29 days to average).

 

Santa never left me a Smart Meter or any Battery's. Exported 1.024Mwh to PEA (4300Bht). It would have been nice of them to refund in kind 2,250Bht..

Monthly Solar Yeild December.png

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Sorry to hear that @Thaifish.

 

Yeah it really is a shame that you don't have that reverse spinning meter, that would help a lot and as I have the same meter as you have, the more important part, for my future installation, is now the availability and also able to easily upscale the Batteries!

 

Also thanks for the help!!!

 

:wai:

Edited by MJCM
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  • 3 weeks later...
On 9/2/2021 at 10:27 AM, JBChiangRai said:

I bought the Hybrid inverters direct from MUST Solar in China, they are 5.5Kw models and cost 16,333 baht delivered all duties paid. I bought the MUST Grid-Tied inverters from Thai Jeen Solar on Lazada. I had to add those because I export on average 80 KwHr’s per day (peak 120) and we use about that too as we run all the 11 air conditioning units 24/7 and keep the house at a constant temperature.

 

The MUST Hybrid Inverters are extremely poor at exporting power to the grid.

Could you please explain what do you mean by that and state your hybrid inverter model. I'm considering a 5Kw Pro series hybrid fanless one, specs do look quite solid and the prece is quite attractive compared to similar spec Sofar Solar one (HYD5000-ES).

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