How about a solar car port on a budget?

[TimeMachine]

When electric companies do things like charge you for feed in or give a few baht for your efforts do they get you to sign an agreement. Or are they entitled to do whatever they want without notice?

Edited October 14, 2023 by TimeMachine

[Crossy]

3 minutes ago, TimeMachine said:

When electric companies do things like charge you for feed in or give a few baht for your efforts do they get you to sign an agreement. Or are they entitled to do whatever they want without notice?

 

To get an official feed-in tariff there's a whole stack of paperwork and regulations to deal with. You need to use approved equipment and an approved installer. Feed-in rate has been increased, but it's still around half of the import rate. This can make the ROI too long for many.

 

The contract is quite long and certainly used to have some punitive clauses if you didn't make enough juice.

 

Running the numbers, DIYers would likely be better off going with hybrid inverters and energy storage.

[TimeMachine]

10 minutes ago, Crossy said:

 

To get an official feed-in tariff there's a whole stack of paperwork and regulations to deal with. You need to use approved equipment and an approved installer. Feed-in rate has been increased, but it's still around half of the import rate. This can make the ROI too long for many.

 

The contract is quite long and certainly used to have some punitive clauses if you didn't make enough juice.

 

Running the numbers, DIYers would likely be better off going with hybrid inverters and energy storage.

Planning to connect up a solax X1 boost  5kw grid tied inverter to a spinning disc meter.

Does anyone know the technicals on how the inverters that are setup to stop feed in know how they determine if power is going into the homes load or the grid? I believe a current transformer needs hooking up but have also read some inverters just know without the CT albeit a less accurate result.

[Crossy]

3 minutes ago, TimeMachine said:

Planning to connect up a solax X1 boost  5kw grid tied inverter to a spinning disc meter.

Does anyone know the technicals on how the inverters that are setup to stop feed in know how they determine if power is going into the homes load or the grid? I believe a current transformer needs hooking up but have also read some inverters just know without the CT albeit a less accurate result.

 

It does depend upon the inverter, pure grid-tie tend to want a CT but the on/off grid hybrids (many run without a battery) have separate grid and load connections so they don't need an external CT.

 

The Solax has an external CT.

 

[TimeMachine]

30 minutes ago, Crossy said:

 

It does depend upon the inverter, pure grid-tie tend to want a CT but the on/off grid hybrids (many run without a battery) have separate grid and load connections so they don't need an external CT.

 

The Solax has an external CT.

 

Cheers. I think the plan will be hook up CT and stop feed back from the get go to avoid any hassle from authorities. I'll add a few batteries on a 240v outlet to capture a little for blackouts. I'm guessing the CT clamp must be between grid and load section of the 240v wire.

Edited October 14, 2023 by TimeMachine

[TimeMachine]

3 hours ago, Crossy said:

 

It does depend upon the inverter, pure grid-tie tend to want a CT but the on/off grid hybrids (many run without a battery) have separate grid and load connections so they don't need an external CT.

 

The Solax has an external CT.

 

Trying to find one of these CT clamps. Someone is taking a guess that a 100a/30ma simple clamp from AliExpress will do the trick. Worth a try? I'm guessing if anybody selling the original it will be at a stupid price for a coil of wire.

[Crossy]

3 minutes ago, TimeMachine said:

Trying to find one of these CT clamps. Someone is taking a guess that a 100a/30ma simple clamp from AliExpress will do the trick. Worth a try? I'm guessing if anybody selling the original it will be at a stupid price for a coil of wire.

 

They usually come with the inverter. If not, the inverter manual should tell you the correct ratio, most seem to need 3000:1.

 

Your 100A/30mA should do the trick if that's the required ratio.

[Crossy]

The numbers for October.

A somewhat "variable" month reflecting the weather at this time of year. Best day was 39.7kWh, worst a miserable 13.9kWh.

It still equates to 4,012Baht we haven't paid to PEA.

 

[gamb00ler]

System is SMILE-T10-HV-INV inverter with 25 440w panels and 16.4KwH of storage, located in CM.

 

Total generation 1047.7     Total consumption 1508.5
October numbers:
 

[Crossy]

Here are our numbers for November. Not the best we've had, spoiled by a few bad days but I'm not complaining.

 

About 4,188 Baht that we've not paid to PEA vs the 500 Baht we did pay them 

 

[Crossy]

Happy New Year everyone.

 

The numbers for December, another 4,600Baht that PEA didn't get

 

 

I also did a month-by month plot comparing 2023 with 2022.

Overall total pretty similar but some interesting variations (note that the vertical scale starts at 600 kWh so variations are exaggerated).

 

[Pink7]

3 hours ago, Crossy said:

Happy New Year everyone.

 

The numbers for December, another 4,600Baht that PEA didn't get

 

 

I also did a month-by month plot comparing 2023 with 2022.

Overall total pretty similar but some interesting variations (note that the vertical scale starts at 600 kWh so variations are exaggerated).

 

Nice Numbers. Happy New Year too.

 

 

Pink

[Crossy]

January production, not wonderful and several really miserable days 😞

 

 

[Crossy]

February numbers, not particularly wonderful.

 

We just took delivery of 4 more 380W panels which will take us to just over 12kWP on the car port

 

 

The overall percentage solar/grid was reduced by the presence of family over the long weekend. Having all the A/C running really does hit the bill  

 

[ExpatOilWorker]

1 hour ago, Crossy said:

February numbers, not particularly wonderful.

 

We just took delivery of 4 more 380W panels which will take us to just over 12kWP on the car port

 

 

The overall percentage solar/grid was reduced by the presence of family over the long weekend. Having all the A/C running really does hit the bill  

 

2 hours and 16 minutes full solar power per day on average. Why so low?

February wasn't particularly rainy, but maybe cloudy? Pollution? The position of ur panels?

The national average is 4.5 hours.

[Crossy]

2 hours ago, ExpatOilWorker said:

2 hours and 16 minutes full solar power per day on average. Why so low?

February wasn't particularly rainy, but maybe cloudy? Pollution? The position of ur panels?

The national average is 4.5 hours.

 

It's been pretty murky although we are down on the same period last year. Seemingly thin, high cloud makes more difference than one might expect.

 

The good days are pretty much average for our system, so I don't think there's actually anything wrong, the bad days slug it

 

Year on year variations can be rather large.

October 2022 was when we lost one inverter for a while due to a software failure.

July 2023 was our panic when we thought PEA might have seen our meter going backwards.

 

[lom]

5 hours ago, ExpatOilWorker said:

2 hours and 16 minutes full solar power per day on average.

How do you get that number? You can't take the production and divide by panel capacity and deriver solar hours from that.

I assume Crossy doesn't have any batteries, his ratio between produced and bought power is about the same as I got the first month I test ran my system before batteries arrived. 

 

 

Edited March 2 by lom

[Crossy]

11 minutes ago, lom said:

How do you get that number? You can't take the production and divide by panel capacity and deriver solar hours from that.

I assume Crossy doesn't have any batteries, his ratio between produced and bought power is about the same as I got the first month I test ran my system before batteries arrived. 

 

We do have batteries, but only about 6kWh.

 

If you look back in this thread there are monthly posts, produced/total is much nearer 90% in some months, depends who is here and just how much A/C they use.

 

Hammering down right now, array is only producing about 350W

[ExpatOilWorker]

25 minutes ago, lom said:

How do you get that number? You can't take the production and divide by panel capacity and deriver solar hours from that.

Why not?

 

1694512963-thailand-20solar-20information.avif

[lom]

4 minutes ago, ExpatOilWorker said:

Why not?

because production is dependent on usage, if you not utilize the panels to 100% then you will get a flawed solar hours value.

I utilize my panels to 100% until 1pm, then batteries are charged and remaing production goes to consumption only.

My 52-54 KWh daily production  from 14KW of panels would be slightly less than 4 solar hours but I have full production from 7.30am covering the consumption then consumption+ battery charge from 8.00am to 1.00pm  and then until 5 pm covering consumption.

I have been up to 70KWh of production when I tested grid feed-in which would give 5 solar hours according to your calculation.

Edited March 2 by lom

[Crossy]

People.

 

If you want to start a discussion about theoretical vs actual solar production please start your own thread.

 

Further off-topic posts of this nature will be removed without notice.

[lom]

Sorry Crossy

[Crossy]

Just to calm the waters.

 

Our system is arranged so that we can use every joule it makes, if it's not immediately consumed it charges the batteries, when the batteries are full we export to the grid and spin the disc-type meter backwards (naughty I know), it goes forwards again at night.

 

In February 2024 we made at total of 2.84GJ.

 

A good, sunny month (May 2023) the same system produced 4.34GJ

 

1kWh = 3,600,000J

[Muhendis]

3 hours ago, Crossy said:

1kWh = 3,600,000J

I wondered about this so had a quick look at Wiki and here is the result:-

 

James Prescott Joule FRS FRSE (/dʒuːl/;[1][2][a] 24 December 1818 – 11 October 1889) was an English physicist, mathematician and brewer, born in Salford, Lancashire. Joule studied the nature of heat, and discovered its relationship to mechanical work. This led to the law of conservation of energy, which in turn led to the development of the first law of thermodynamics. The SI derived unit of energy, the joule, is named after him.

He worked with Lord Kelvin to develop an absolute thermodynamic temperature scale, which came to be called the Kelvin scale. Joule also made observations of magnetostriction, and he found the relationship between the current through a resistor and the heat dissipated, which is also called Joule's first law. His experiments about energy transformations were first published in 1843.

 

Man after my own heart.

 

Being as how he was borme not too far from Manchester, I wonder is our learnéd author might have met him.......

Edited March 2 by Muhendis

[Crossy]

Well, here we are, April 1st.

But the March production was no joke with daily production ranging from pretty amazing to amazingly awful.

 

Note that we are now at 12.1kWp of panels from 03/03/24.

 

 

 

This is our total daily energy consumption (solar + PEA). 

 

Family (grandkids) arrived from a snowy UK on the evening of the 28th hence the sudden jump due to 4 x teens (3F, 1M) taking 1-million-year hot showers and running the A/C at arctic temperatures.

They are also eating us out of house and home  

Love them all really

 

[Crossy]

Interestingly (or maybe not) we have a mixture of 300W, 340W and 380W, average size is 338W.

 

On a per-panel basis we get about 1.1kWh per-day on average.

 

 

[lom]

Interesting to see that I'm not the only one to have a consumption peak 31/3, our daily consumption during March was 52KWh ± 3KWh with 0.5KWh daily purchase from the grid (because current transformers in wrong place) and no feed-back to grid.

31/3 we had the record consumption of 68.4KWh and we had to buy 6KWh, I'll have to rectify that purchase today 😁

 

Edited April 1 by lom

[gamb00ler]

Here's my March chart from Hang Dong district of Chiang Mai.

The most significant changes were the acquisition of an EV and the addition of a 3rd battery (total 24.58 Kwh capacity).

The battery was added a few days after the EV.

PV generation = 1,250 KWh

PEA consumed = 614 KWh

 

 

Edited April 1 by gamb00ler

[Crossy]

CrossyPowerCentral has expanded somewhat with the addition of 3 more 340W panels taking us to 13.1kWp on the car-port.

 

 

Our motley collection of panels demonstrates just how widely the dimensions of panels vary. Except for the baby 100W panel on the right (which powers some of our floodlights) all those panels are 300-340W. This is one of the disadvantages of building a "bitsa" system.

 

Energy storage has also expanded, these are "Archibald" XDLP48-100 (51.2V 100Ah) LiFePO4 battery packs. Sadly, they've been in storage for at least 3 years and I'm not convinced they used new cells even then. They all measure at about 60Ah from full charge to BMS cut-off, they may improve as they balance with usage cycles.

 

 

I got these packs and a stack of other solar stuff which I'm still inventorying from the estate of a friend who sadly died last year.

 

There are inverters and a stack of panels that I'll need to clear so watch the forum for stuff becoming available.

 

Of course, with all these upgrades we are hitting the limits of our current inverters, so replacements are also on the cards.

 

EDIT Of course, life being life, this collection of stuff came up a week after I'd ordered two new 280Ah 48V packs from Shenzhen Luyuan Technology Co., Ltd.

 

All in USD3,774 for two including DDP shipping to Thailand. Saved a few hundred $$ by ordering them as kits rather than fully assembled. Amy Wan and Shenzhen Luyuan come highly recommended on other solar power forums.

 

https://www.alibaba.com/product-detail/14KW-48V-51-2V-280AH-Pre_1600894719244.html

 

 

 

[Crossy]

The more observant will note that there's a framework at the far end where half a dozen more panels will fit and I've got plans for 14 more on an extension to the front edge of the car port.

 

That would add a further 6.8kWp bringing us to just under 20kWp!

 

Madam has plans for enclosing (and air-conditioning) our ground level space, I'll need all the energy I can get.