Solar energy Incentive
Solar energy Incentive
As a side note, I'm surprised but pleased with the farm system. As suspected, the two cheap solar panels are now covered with dust. I really don't know how much the nephew is using at night but the mornings I go to look, 9:00 or 10:00 AM the CC is blinking that the batteries are fully charged. I instructed the nephew that if the battery voltage drops below 12.2 volts, to shut the system down. He says that the voltage never goes below that. It is working better than the 310 watt panel and the expensive batteries at the house. Peak wattage from the expensive 310 watt panel seldom reaches 220 watts and that is with the panel being aligned as recommended. I have long suspected that 310 watts from that 310 watt panel is highly optimistic. Unfortunately the little meter I am using at home shuts itself down when it gets dark so it is basically useless at the farm. I have to reset it in the mornings.
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Bronze and aluminium also create a galvanic problem.glalt wrote:I think that running aluminum wire from your panels to the house is a sound idea. I certainly wouldn't have any qualms about doing it that way. The problem is joining the copper and aluminum. You will likely want a disconnect between your CC and the panels anyways. The knife type disconnects are cheap and the better ones are bronze. The aluminum wire goes in one end and the copper in the other end thus keeping the different materials away from each other. By having the disconnects you can easily keep an eye on the performance of each set of panels. The MC4 connectors on the panels to the feed wire are weatherproof and should be no problem. Any problems at the panel and aluminum feed wire connection can be easily checked with your multimeter at the knife disconnects.
The aluminium will corrode.
Penetrox or similar will help.
http://www.amazon.com/Burndy-P8A-Oxide- ... B008KLX2RY
Solar energy Incentive
These pastes (denso/penetrox) must be highly conductive? Is petroleum jelly conductive? 
At any rate, as glalt says, I think the MC4 connectors are water-tight, so "should" not have a problem. If so, then I just use MC4 connectors at both ends, as I do on my little system now. An MC4 at the panels, and MC4 at the CC/Inverter side. Should be a good solution, no?
At any rate, as glalt says, I think the MC4 connectors are water-tight, so "should" not have a problem. If so, then I just use MC4 connectors at both ends, as I do on my little system now. An MC4 at the panels, and MC4 at the CC/Inverter side. Should be a good solution, no?
Solar energy Incentive
glalt - So far I have not notice much of a difference before and after cleaning my panels. The cold water on the panels while cleaning does wonders for the power output though. Makes me think of using a sprinkler on my roof during the hot season to cool the panels down... water is so cheap here. This news article states that for a large commercial solar installation cleaning the panels often was not economical.
http://scienceblog.com/65232/cleaning-s ... iego-find/
Of course California has far less dust/pollutants in the air than here. I suppose for we un(der)employed folks a few minutes of our time to clean the panels isn't a problem, but it might not be much of a benefit either. Anyway, I would not worry too much about the dust. Of course freshly clean panels are "suay maak" for the neighbors.
http://scienceblog.com/65232/cleaning-s ... iego-find/
Of course California has far less dust/pollutants in the air than here. I suppose for we un(der)employed folks a few minutes of our time to clean the panels isn't a problem, but it might not be much of a benefit either. Anyway, I would not worry too much about the dust. Of course freshly clean panels are "suay maak" for the neighbors.
Solar energy Incentive
Panel Orientation
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It looks to me that solar panel power production during the dry season here will be far higher than during the rainy season. If you are in a situation where you are off-grid and do not want to use a generator as backup, then you would have to oversize your solar panel array. That is, the solar panel array would have to be large enough to power the home throughout the rainy season, but in the dry season you would be making too much power. Quite wasteful. This article discusses something I had been wondering about for a while and would seem to be very beneficial here. That is, panel orientation that provides more balanced power output between direct light and diffused light....
http://scienceblog.com/52948/solor-towe ... up-to-20x/
Interesting, but not ready for prime time
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It looks to me that solar panel power production during the dry season here will be far higher than during the rainy season. If you are in a situation where you are off-grid and do not want to use a generator as backup, then you would have to oversize your solar panel array. That is, the solar panel array would have to be large enough to power the home throughout the rainy season, but in the dry season you would be making too much power. Quite wasteful. This article discusses something I had been wondering about for a while and would seem to be very beneficial here. That is, panel orientation that provides more balanced power output between direct light and diffused light....
http://scienceblog.com/52948/solor-towe ... up-to-20x/
Interesting, but not ready for prime time
Solar energy Incentive
The new generation hybrid inverters can harvest all the energy from your panels year round. The problem is that they are big, heavy and expensive. Of course they are useless if you are not connected to the grid.
http://www.aliexpress.com/item/3000w-on ... 59439.html
The scienceblog article is very interesting. I suspect that within the next couple if years much more efficient panels will be available at reasonable prices. It's good to see that they are working on improving solar systems.
As long as my dusty panels are keeping the batteries fully charged, I'm content to leave them dirty. If/when they no longer keep up, I'll send the wife up on a ladder with a water hose and a squeegee. LOL!
http://www.aliexpress.com/item/3000w-on ... 59439.html
The scienceblog article is very interesting. I suspect that within the next couple if years much more efficient panels will be available at reasonable prices. It's good to see that they are working on improving solar systems.
As long as my dusty panels are keeping the batteries fully charged, I'm content to leave them dirty. If/when they no longer keep up, I'll send the wife up on a ladder with a water hose and a squeegee. LOL!
Solar energy Incentive
Thanks for the link, I hadn't seen that inverter. Still, at nearly $2800 it is rediculously expensive. I guess there still is some place to make a profit in electronics these days.
Solar energy Incentive
Off grid pure sine wave inverters. I sized my original inverter for my small home system. It is 600 watt. The second was for the farm system with expanding the system in mind. It is 2,600 watt. That inverter is right now way oversize for the farm system. The general belief is that the inverters are the weakest link in the systems. I bought an 800 watt spare inverter that is suitable for home or the farm. Since I have an accurate DC ammeter at home, I was curious about efficiency between the three inverters. The fans in the 600 and 800 watt inverters are fairly noisy whereas the 2,600 watt has two fans. Those fans are quiet and they seldom run. My DC ammeter is a class 2 50 watt. The class 2 analog is supposedly more accurate than the more common class 2.5 models. The bottom line here is that if there is any efficiency difference between the 600 watt, 800 watt and the 2,600 watt, it is VERY little. I would have expected the 2,600 watt to be the least efficient with the light load. That appears to NOT to be the case. This whole deal is a constant learning process. Based on using three different inverters, I have come to the conclusion the the oversize unit will likely last longer and will stay cooler. There is very little if any difference in efficiency.
The next trip I make to Udon, I intend to buy another cheap 280 watt panel and test it under the EXACT same conditions that I am using with the expensive 310 watt panel. I want to learn as much as possible because there is a possibility that I may build a new house off grid and that will have to be 100 percent solar.
Does anyone have experience with solar hot water water systems?
The next trip I make to Udon, I intend to buy another cheap 280 watt panel and test it under the EXACT same conditions that I am using with the expensive 310 watt panel. I want to learn as much as possible because there is a possibility that I may build a new house off grid and that will have to be 100 percent solar.
Does anyone have experience with solar hot water water systems?
Solar energy Incentive
I know a wee abit about solar water heaters..whats your question?
Solar energy Incentive
I'd like to know how much difference there is between the high tech vacuum tube types and the simpler more or less home made units. Do you use an insulated tank and how big of a tank? If the collectors are mounted on the roof, will the no pump needed thermal siphon method still circulate the water from the tank on the ground to the collectors? Obviously we don't need to worry about anything freezing. I would be very happy keeping the water about at about 40 C. I'd prefer not to have to use extra plumbing for mixing valves and extra pumps to regulate the water temperature. Simpler is better. The commercial units advertise 70 to 80 C water temperature.
Solar energy Incentive
I said a wee bit..hahaha
one mate across the valley has the newish glass tubes model, apparently heated the water quicker, but he had problems with leaks and broken glass..He tried to sell them to other mates but not very successful..
The guys at each end of my road have the older flat glass panels with the metal tubes inside , and the round cylinder on the roof which I think has a plastic bag inside..
and my mate who works as the local solar installer, has the same flat model, but he has attached the panel to his deck railing at about head height off the ground, and on the end of the deck behind it he has built a cupboard and inside is an ordinary house water cylinder..standard house size ( 4ft high) cant remember how many gallons /litres..the size of tank depends on how much hot water you want..
the idea is to keep the length of pipe between panel and cylinder as short as possible, as you loose heat out of the pipes...we use a round rubber sponge type material ( seen on some surfboard racks ) to insulate the pipes...I dont think there is a pump needed, the hot water displaces the cold water and cirulates by itself..the pump only comes in bwteen the tank and house, so when you turn the tap on, if you havent got a header tank, the pump will come on, and shut off when you turn the tap off....if you PM I will give you an email address for my solar installer mate who happens to be married to a Thai, so knows Thailand conditions....
one mate across the valley has the newish glass tubes model, apparently heated the water quicker, but he had problems with leaks and broken glass..He tried to sell them to other mates but not very successful..
The guys at each end of my road have the older flat glass panels with the metal tubes inside , and the round cylinder on the roof which I think has a plastic bag inside..
and my mate who works as the local solar installer, has the same flat model, but he has attached the panel to his deck railing at about head height off the ground, and on the end of the deck behind it he has built a cupboard and inside is an ordinary house water cylinder..standard house size ( 4ft high) cant remember how many gallons /litres..the size of tank depends on how much hot water you want..
the idea is to keep the length of pipe between panel and cylinder as short as possible, as you loose heat out of the pipes...we use a round rubber sponge type material ( seen on some surfboard racks ) to insulate the pipes...I dont think there is a pump needed, the hot water displaces the cold water and cirulates by itself..the pump only comes in bwteen the tank and house, so when you turn the tap on, if you havent got a header tank, the pump will come on, and shut off when you turn the tap off....if you PM I will give you an email address for my solar installer mate who happens to be married to a Thai, so knows Thailand conditions....
Solar energy Incentive
PM sent.
Solar energy Incentive
Going after the Govt on the solar roof program. I don;t think it was about the government it was about price gouging.
Looks like that backfired on companies their own fault. We qualified and the lowest price we got a for a 5KW system was 350K. So we didn't use it. The electric company itself was very helpful.
http://www.bangkokpost.com/business/new ... e-defended
Looks like that backfired on companies their own fault. We qualified and the lowest price we got a for a 5KW system was 350K. So we didn't use it. The electric company itself was very helpful.
http://www.bangkokpost.com/business/new ... e-defended
I reserve the right to be wrong, mispell words type badly. leave words out of sentences because my mind works faster then my fingers. To be an OLD GIT I've earned it
Solar energy Incentive
Maaka, I have been in contact with your friend. He seems like a great guy. Just like my solar electric, I plan to design and build a small system to learn from here at home. If/when we build a house off grid, I will have learned enough to build a system that will easily supply an off grid house.glalt wrote:PM sent.
I have two solar hot water quotes. One is 54,000 baht and the other is 38,000. I cannot use a factory built unit at home because I can't get enough sun thus just a small unit to learn from for now. Even If I could use the factory built hot water systems, like the Thai solar electric systems, the payback would take far too long.
Solar energy Incentive
Rodger that Glalt...glad you hooked up..yup my young mate does solar installation as a business on our island, which has no grid, so he knows his stuff, and is an accommodating sort of fella, and of course is married to a lovely Thai lady from Kalasin, so knows the weather conditions and all in the Land of Smiles..he is always good to use as a sounding board for ideas...me I am just the broad black and white picture ideas, but hes the colored HD version..hahaha
Solar energy Incentive
I finally made the trip to Udon Thani on Friday. I went to Amorn on Saturday to buy another cheap 280 watt poly solar panel. Surprise, surprise, no have. They have been replaced with 275 watt panels and there were not too many of them. There was a big stack of the expensive 310 watt mono panels. The 275 watt panels are priced at 5,500 baht. I wanted a 280 watt panel and a DC water pump. No water pumps in stock. Questions about the 280 watt panels were met with a blank look. MC4 connectors ? Mai mee. Service at Amorn leaves a lot to be desired.
When I got home on Sunday, I looked at their web page and neither the 310 watt mono panel nor the 280/275 poly panels are shown. The missing DC water pump is still shown.
I took the 310 watt panel out of the holder and put in the 275 watt. I have been using the 275 for a couple of days now and it is doing a pretty fair job. Tomorrow I will record the different readings from the watt meter for a few days and then swap back the 310 watt and do the same. I will report the differences. I can say at this point that the 310 watt panel seems to have a little more output but not a lot. It certainly is not worth the premium price. Both panels will be oriented exactly the same and both use the same wiring and components.
When I got home on Sunday, I looked at their web page and neither the 310 watt mono panel nor the 280/275 poly panels are shown. The missing DC water pump is still shown.
I took the 310 watt panel out of the holder and put in the 275 watt. I have been using the 275 for a couple of days now and it is doing a pretty fair job. Tomorrow I will record the different readings from the watt meter for a few days and then swap back the 310 watt and do the same. I will report the differences. I can say at this point that the 310 watt panel seems to have a little more output but not a lot. It certainly is not worth the premium price. Both panels will be oriented exactly the same and both use the same wiring and components.
Solar energy Incentive
I think the 310watts are mono while the 275's are poly's . The polys have slightly lower output (% wise ) but will have less fallback from temp . If you put the 310 in the same string as a 275 ( or other ) the lowest panel will have the performing output of the system ( as far as im told ) . This means your 310 will act like a 275 . This is important if you have shadow on 1 of the panels as it would infect the output on all panels in the string .glalt wrote:I finally made the trip to Udon Thani on Friday. I went to Amorn on Saturday to buy another cheap 280 watt poly solar panel. Surprise, surprise, no have. They have been replaced with 275 watt panels and there were not too many of them. There was a big stack of the expensive 310 watt mono panels. The 275 watt panels are priced at 5,500 baht. I wanted a 280 watt panel and a DC water pump. No water pumps in stock. Questions about the 280 watt panels were met with a blank look. MC4 connectors ? Mai mee. Service at Amorn leaves a lot to be desired.
When I got home on Sunday, I looked at their web page and neither the 310 watt mono panel nor the 280/275 poly panels are shown. The missing DC water pump is still shown.
I took the 310 watt panel out of the holder and put in the 275 watt. I have been using the 275 for a couple of days now and it is doing a pretty fair job. Tomorrow I will record the different readings from the watt meter for a few days and then swap back the 310 watt and do the same. I will report the differences. I can say at this point that the 310 watt panel seems to have a little more output but not a lot. It certainly is not worth the premium price. Both panels will be oriented exactly the same and both use the same wiring and components.
Solar energy Incentive
About a week and a half ago I looked at the amornsolar.com website and noticed that 2 of the previous 4 pages of products were no longer there. This included the 3kw and 5kw GTI systems that I was seriously considering buying. So we called amornsolar and they said that they were still selling everything, they were just updating their website. So, as of this morning I see that the website is still missing the products.
glalt - are you sure that the 275W panels are not the same as they have had in there for a long time? Some of those panels are 280W (just have to search for the right code on the panels). I have not been in Amorn for a few weeks so I don't know, maybe they sold out of the other panels, or maybe they were just feeling guilty putting a "280W" sign on those panels as only a few were actually 280W. I was looking at the datasheet for the panels and finally noticed the "NOCT" table. It is based on the "Normal Cell Temperature" testing, unlike the STC. In the "NOCT" table they clearly show "maximum power" as 201W (rather than 275W). That is testing with ambient temperature at 20C (the cell temperature at 45C). Yesterday I believe the temperature was around 34C here, so that 201W would have to be derated by another 0.33%/C past 20C, or 4.62%, or about 9W... down to 192W. The NOCT testing assumes 800W/m2 though, but our AM now is probably around 1.1-1.2 so the irradiance should be higher, offsetting the temperature difference.
I've been trying to upload the datasheet for about fifteen minutes but udonmap.com keeps hanging on it so maybe i will post it later.
A little update on my system. I believe I fried the super cheap ($12) 20A solar MPPT charge controller that had been working fine for 3-4 months now. The impatient person I tend to be, I switched the solar panels onto the CC before the battery side was switched/connected. This is a no-no with solar CCs. So, my bad, not the CC's fault. After that, the CC ramped the battery voltatge past 32V (on a 24V string), before I shut it down. I believe it damaged one of my batterries a bit. Live and learn... thankfully the battery only cost around $12.
glalt - are you sure that the 275W panels are not the same as they have had in there for a long time? Some of those panels are 280W (just have to search for the right code on the panels). I have not been in Amorn for a few weeks so I don't know, maybe they sold out of the other panels, or maybe they were just feeling guilty putting a "280W" sign on those panels as only a few were actually 280W. I was looking at the datasheet for the panels and finally noticed the "NOCT" table. It is based on the "Normal Cell Temperature" testing, unlike the STC. In the "NOCT" table they clearly show "maximum power" as 201W (rather than 275W). That is testing with ambient temperature at 20C (the cell temperature at 45C). Yesterday I believe the temperature was around 34C here, so that 201W would have to be derated by another 0.33%/C past 20C, or 4.62%, or about 9W... down to 192W. The NOCT testing assumes 800W/m2 though, but our AM now is probably around 1.1-1.2 so the irradiance should be higher, offsetting the temperature difference.
I've been trying to upload the datasheet for about fifteen minutes but udonmap.com keeps hanging on it so maybe i will post it later.
A little update on my system. I believe I fried the super cheap ($12) 20A solar MPPT charge controller that had been working fine for 3-4 months now. The impatient person I tend to be, I switched the solar panels onto the CC before the battery side was switched/connected. This is a no-no with solar CCs. So, my bad, not the CC's fault. After that, the CC ramped the battery voltatge past 32V (on a 24V string), before I shut it down. I believe it damaged one of my batterries a bit. Live and learn... thankfully the battery only cost around $12.
Solar energy Incentive
- 175 watt poly
The 175 panel has a different data plate.
Solar energy Incentive
Everytime I try to upload the .jpg file I get returned to a blank page...
http://www.udonmap.com/udonthaniforum/p ... 42&t=29234
They are second hand car/light truck batteries. I just go into the town and go around to two or three shops and look for the best battery I can find. I take a volt meter and an impedance tester. Sometimes I will find a decent battery, then go do something else for an hour or so and come back and check the battery again. I seem to be getting better at the task as the last battery I bought (for 500 THB) has a voltage about 12.73V after being off charger for more than 5 hours. That means it is pretty close greater than 90% of design capacity. Most of the batteries I check are quite bad, but somewhere in the two or three shops there usually is a decent one to buy. Don't ask me why a nearly new battery would be be sitting in an auto-parts/repair shop but they sometimes do.
http://www.udonmap.com/udonthaniforum/p ... 42&t=29234
275W panel? Last time I was in Amorn the 275W Suntech were mixed in with the 280W (better binout) Suntech panels, and both in the same stack upon the wall, and labelled 280W poly panels. If you look for the I3 label on the side, then that will be a 280W panel and the Suntech data plate (like the one you posted) will read 280W. Just look at the white label on the side for I3. Last time I did not see any I3, just I2 and I1 (the worst binout).glalt wrote: What sort of a battery do you get for $12 ? I'm not having a lot of luck getting good data from the 175 watt panel. Too cloudy. When I change back to the 310 watt mono, it's not likely that the clouds will be the same.
The 175 panel has a different data plate.
They are second hand car/light truck batteries. I just go into the town and go around to two or three shops and look for the best battery I can find. I take a volt meter and an impedance tester. Sometimes I will find a decent battery, then go do something else for an hour or so and come back and check the battery again. I seem to be getting better at the task as the last battery I bought (for 500 THB) has a voltage about 12.73V after being off charger for more than 5 hours. That means it is pretty close greater than 90% of design capacity. Most of the batteries I check are quite bad, but somewhere in the two or three shops there usually is a decent one to buy. Don't ask me why a nearly new battery would be be sitting in an auto-parts/repair shop but they sometimes do.