Reader question: Who has (recent) experience with solar panels?

Dear,

As in that last message, a generator is perhaps the cheapest and not expensive.
Honda supplies light “silent” and compact generators and provided two or three jerry cans of gasoline (2-stroke?)
do you have spare.

Well, maybe there is not enough power to power a washing machine, dishwasher and iron, but more than enough for TV, radio and LED lighting.

Dirk

I have had 3 solar panels for 18 years now and I am very satisfied with them, only the friends of the PEA (Provincial Electricity Authority) have messed things up, they think it is dangerous for them if the meter turns backwards so that if they work on the cables and the have turned off electricity that one of the motors can still fall dead from my solar panels power. I explained to the basket if he wants to talk about cycling he must first learn to cycle, in other words he must first learn about solar panels and then he will learn as soon as there is no more power on the system, the solar panels will no longer supply power. But that put I think bad blood and now got a meter that cannot turn back so during the day it stands still and at night it turns up the position so I have little benefit left I went from 6500 Bht/month without solar panels to 1700 Bht/month with and now 2500Bht/month with the fucking meter! and then I have the trick that I turn off all refrigerators at 4 am and start them again at 8 am when the sun is shining. Batteries are not an option as they are prohibitively expensive and have a lifespan of only a few years.

Solar panels are 12V, if you install (a 2nd?) electricity network at home in 12V in collaboration with LED lighting, you can use simple batteries in dark light / radio etc, refrigerator also works (camping model)

If you do washing and heavy power tractors during the day, when the sun is out, you should still come a long way.

It's mainly about, what do you use in kW in the evening?
Heavy boys are of course the refrigerator, washing machine and AC (possibly), if you cook electrically, plates or microwave or otherwise, that costs power.
In terms of lighting, you can of course use as many LED lamps as possible, which saves money.
You have LED lamps of 10 W with 1000 lumens, which give good light. Can be less natural, saves, but gives less light, eg 3 w 300 lumens.

You see batteries of 12V 200Ah on alibaba. Varying in prices and warranty, everything ex transport costs of course. These weigh +/- 60 kg/piece.
Lipo batteries again save a lot of weight, but are more expensive and require a special charger.
Smaller batteries 90 Ah weigh less, but then you need more.

With 12V 200Ah you can theoretically get an inverter 230V 10 Ah on the secondary side, all that for 1 hour, after that the battery is empty. Now you will not use 10 A continuously in an hour (??), but this is not possible due to cabling.
so you need several batteries.
Whatever you want, of course, and depending on what you want to feed. You see various batteries and prices,

Cabling is also an issue, the larger the diameter of the cable, the less power loss, so more efficient, so better. Also the material, is it pure copper or an alloy? Is used in Asian countries to reduce cable costs. You have to connect several batteries in parallel.

As the amperage increases on the primary side (12V), the cable can get warm and possibly even hot with insufficient diameter, after all 200 A is quite a bit. I actually wonder which cable should be for it, since at 12V max 30 amps can flow through a 4 mm2 cable at a distance of max 1 meter. https://www.rfsystems.nl/techniek/Kabeldoorsnede_12V_24V_LED.pdf
So briefly to the inverter. 200 A from a battery is therefore NOT an option.

By doubling the cables, you can then draw a maximum of 60 A from a battery. i
This means that you need at least 10 batteries for 230 A secondary side (4 volts) and have this secured on EACH battery (60 A). So is 240 A primary and secondary 12(.5217) A
I am only left with the problem, where the cables come together and 240 A flows. So it should be a copper strip attachment
But the batteries will continue to deliver longer. At 10 A continuous, so about 3 hours.
Maintenance also plays a role, as resistance increases when the cable is oxidized and efficiency drops. And it is humid in Thailand. Greasing with a non-conductive grease (vaseline) on the connections helps a lot.

With a 15-year warranty, the battery costs USD 200 per piece excluding shipping, transport, so they weigh about 60 kg.
thus a train of thought

I also had the idea of ​​doing something with solar energy, but I have shelved the project because it was “not profitable”.
If you want to work completely autonomously, so no mains connection, then you need a decent installation with sufficient storage capacity. Also keep in mind that the panels here achieve a lower efficiency than in Europe due to the heat. By the way, you need “light” and not heat.
Start with a proper calculation of the required power over a period of 24 hours. Multiply this by factor 4 to calculate the capacity of the panels. Know that you only have half of the sunlight per day, so you need to be able to produce enough during the hours of sunlight to cover the non-productive hours. That is as a factor 2 and the other 2 to absorb the losses regarding efficiency and consumption of the peripheral equipment, voltage regulator, converter to 220V and also wa So you will need a large storage capacity.

I'm thinking about it too. Not so much to save money but more to cope with the regular power outages here on Samui, Electrical equipment still takes a hit every time the power goes out. I was thinking and solar panels with a Tesla battery. However, they are indeed very pricey