Solar panels for private homes

[Agusts]

I've been interested in a kind of hubby or small business installing buying/selling solar panels for private homes, in countries with so many sunny days, it sounds like a good idea...

 

But as I understand it there is no goverment subsides in Thailand for this, and no arrangement with power companies to just plug in your excess power and get paid for it, like in UK and Europe...

 

From news it says they are working towards changing regulation and allowing all this, I found these two links (not allowed to post)  that I think saying something about this, p2p power trade, Google search for these topics: 

 

 

BCPG seeks p2p power trade

 

EGAT to run solar power trade test

 

I think large enterprise solar power genetation is available here, but not for small or private homes...

 

Any more info from guys who are more clued in to this subject will be appreciated...

 

Edited February 25, 2020 by Agusts

[blackcab]

Moved to the Electrical Forum. Lots of solar PV knowledge there.

[Crossy]

In the past every man and his dog was jumping on the solar bandwagon, there was almost no enforced regulation and people were just spinning the meter backwards during the day. Nobody cared unless you became a net-exporter of power.

 

Then along came the government sponsored My Solar Roof scheme with a useless FIT, long contract and a list of approved equipment (which of course attracts premium prices) and approved installers (ditto). DIY isn't permitted, or is at least very difficult.

 

We spoke to our local PEA chaps about simple net-metering (spin the meter backwards) and DIY installation. "Cannot" was the response. The rather less official response from the supervisor was "don't let the meter reader see the meter going backwards"  

 

There are at least three outfits doing solar within 15 minutes drive of our place (northern BKK) and the big box players are also doing solar (with installation).

 

Our installation is here:-

 

 

Note that the standing load during the day is arranged so that the meter never really reverses and I've got an Arduino controlled dummy load (still in development) which dumps excess power on the days the meter reader usually turns up.

 

I suspect that you've really missed the boat on the "do installations as a hobby" scene.

 

 

[Crossy]

11 minutes ago, pdtokyo said:

what's the PEA office

 

Sorry, the PEA is the Provincial Electricity Authority, they do everything to do with supply, metering, inspection outside of metropolitan Bangkok (where it's MEA).

 

You will have plenty of dealings with PEA if you are building a home, particularly if there isn't a 220V supply right outside the gate.

 

I'm probably being over cautious with the meter going backwards, there must be thousands of other installations all over the place which don't care, but I don't want to attract any attention. Our panels aren't visible from the road so I'm not giving anyone any reason to poke around.

 

I've heard of one person who got into trouble over a big grid-tie solar installation, but I suspect there is rather more to that story. IIRC all that actually happened was that he was told to disconnect it from the grid and they fitted a meter with an anti-reverse gear. He was soon back on line with a hybrid system storing excess power in batteries to use at night.

[Crossy]

Yeah, Brit here (Bolton).

 

The PEA will probably put another meter on the pole with MiL's. 

 

What happens on the load side of the meter is your problem, but even here there are standards and you will have to pass an "inspection" to get a permanent supply and pay 4 Baht per unit rather than the 8 Baht for a temporary "construction" supply.

 

It's all good fun.

[Agusts]

Thanks for the info on solar panel installations. As I pointed to those articles maybe some changes coming and maybe Thailand authorities decide to loosen up their rules and grip, but who knows.... 

 

There is huge potential here with all the sun and barely anyone using solar panels,  but the market has to be regulated and opened up properly for this to take off, like in the west - authorities monopolizing and restricting it will not help. Time will tell...!

[sometimewoodworker]

1 hour ago, Agusts said:

maybe some changes coming and maybe Thailand authorities decide to loosen up their rules and grip

555555555555

[David B in Thailand]

The OP can walk into any Global House Store (when they open up again) and see a nice display on solar options both off grid and tie in. Easy to do the math. HomePro also has a display with prices of solar power options for a home in Thailand. There are half a dozen stores selling solar equipment in Buriram,  There are expats who design and install solar systems large and small in Buriram and Surin Province with actual customers. This blog shows a large solar system power a nice home in Surin Province. 

https://ecohousethailand.wordpress.com

 

[Crossy]

On 3/25/2020 at 10:46 AM, Agusts said:

Thanks for the info on solar panel installations. As I pointed to those articles maybe some changes coming and maybe Thailand authorities decide to loosen up their rules and grip, but who knows.... 

 

Nah, if anything they're tightening things, there are at least two members who have been caught out doing net-metering (spinning the meter backwards) and have had no-reverse meters installed.

 

At this time I would advise against an installation which exports significant power, if you can control it so it doesn't export when the meter reader is about that would help but no warranty implied or inferred. 

 

I've adjusted our pool pump timing to run during maximum solar generation, but even then we are drifting into export. About -200W for 20 mins or so, time to get Madam to do the ironing at peak solar.

 

There are an increasing number of hybrid inverters which, whilst remaining grid tie (so easy to connect), can be programmed not to export and to store excess solar in batteries. The batteries then send power into the system (still grid-tie without exporting) when the sun is sleeping. 

 

[Metropolitian]

I will have to think about DIY mechanism to bypass the excess generated power to anything internal. (batterypacks, pumps,.. )

With some microprocessors (PI, duino,..) and sensors (amp/volt) and maybe a script to read the modbus data from the meter. it is all possible.

Unless the hybrids drops in the comfort price range.

Still, doing some projects are nice despite the costs ????

[BritManToo]

1 hour ago, Crossy said:

There are an increasing number of hybrid inverters which, whilst remaining grid tie (so easy to connect), can be programmed not to export and to store excess solar in batteries. The batteries then send power into the system (still grid-tie without exporting) when the sun is sleeping. 

 

I've been looking at the off grid hybrids, powered by the grid/battery/solar and with their own 220V ac output.

Do we really need to connect back to the grid, if they won't let us spin?

Around 12k for 2.4Kw

https://www.lazada.co.th/products/3000kva-2400w-sine-wave-off-grid-24vdc-220vac-50a-pwm-30a-ac-i634284407-s1216710875.html

[Crossy]

12 hours ago, BritManToo said:

Do we really need to connect back to the grid, if they won't let us spin?

 

Like many things "it depends".

 

Firstly, I wouldn't get a PWM unit, MPPT is much less wasteful of your valuable solar power.

 

I was looking at the MPPT version of those units, they're great if your load will never exceed the rating of the inverter (and you can parallel them for more power). But you have to supply the load via the unit which may involve extra wiring and will need some form of bypass switch in case the inverter fails / needs servicing. A big plus is that you don't lose power if the grid goes off (UPS functionality).

 

Going with the grid-tie version means simpler wiring, but you will lose power if the supply goes out (but most do have a UPS function too). Your load can be many times what the inverter can provide, the excess is simply drawn from the grid. All the batteries do is provide "curve flattening" so that the inverter provides power over a longer period so the meter just stops. And, if your meter will go backwards (even if not permitted), you can get away with a smaller battery.

 

in either case you need enough battery to absorb all your excess solar of course.

 

Horses for courses.

[BritManToo]

50 minutes ago, Crossy said:

I was looking at the MPPT version of those units, they're great if your load will never exceed the rating of the inverter (and you can parallel them for more power). But you have to supply the load via the unit which may involve extra wiring and will need some form of bypass switch in case the inverter fails / needs servicing. A big plus is that you don't lose power if the grid goes off (UPS functionality).

I'm thinking of just pulling the wires out of the 'living room fuse' and directing both ends to the off grid unit.

So the living room sockets powered by solar and battery first, then mains if the others run out.

 

Would make me 'fai dap' proof as well.

This one can take 16 panels ........

https://www.lazada.co.th/products/hybrid-off-grid-inverter5kva5kw-i429562957-s811424645.html

 

Edited March 27, 2020 by BritManToo

[Crossy]

3 minutes ago, BritManToo said:

I'm thinking of just pulling the wires out of the 'living room fuse' and directing both ends to the off grid unit.

 

Assuming you provide mains to the inverter mains input.

 

As I said, horses for courses, if it does what you want great ????

 

 

[Agusts]

BBC News - A breakthrough approaches for solar power
https://www.bbc.co.uk/news/business-51799503

 

Higher efficiency solar panels on the way, hopefully make them more popular.

 

Very exciting future technology, I wish we could easily invest on these, but I think the few startup companies are all privately owned and too small and risky, I bet they will be swallowed up by bigger players once they have some commercial success...