solar water heater and solar energy?

[leela123]

Hi,

I've just got a small kuti in Chiangrai (43m2) and there are only 2 lights and maybe a laptop in the future. No water heater.

I am thinking of using solar power to reduce costs on the wat.

I've contacted ABO trading in Chiangmai which gives me a reasonable price.

I think I'll get the solar water heater because my friend calculated that I can break even in 5 years.

Not not solar power because it is stand-alone and use batteries to store electricity. Ive read that the batteries are expensive to replace and also not environmentally friendly.

I read some old threads on this but the topics have been archived.

I wonder if some kind soul can give me any advice. All help appreciated. )))

[Greenside]

The guy at ABO seems to know his stuff. Good luck with your project.

[ignis]

How much hot water do you need ?

simply lay a roll of black pipe on the roof........ little more expensive use UPVC pipes, make a frame of say 4 pipes, fit on roof or clip to wall, paint black...... better to buy a 'tap and dye' set so you have screwed in joints and not relies on the glue holding only.. pay for itself in a month......... could also do the same but in the loft under the roof get hot up there and will give warm water and no sun damage............ just a cheap idea.

[Dante99]

How much hot water do you need ?

simply lay a roll of black pipe on the roof........ little more expensive use UPVC pipes, make a frame of say 4 pipes, fit on roof or clip to wall, paint black...... better to buy a 'tap and dye' set so you have screwed in joints and not relies on the glue holding only.. pay for itself in a month......... could also do the same but in the loft under the roof get hot up there and will give warm water and no sun damage............ just a cheap idea.

That black pipe works, know a guy that used it for years here, he pretty much just tossed it up on the roof.

[cloudhopper]

It doesn't sound like you need much power. If you already have access to commercial utility power I recommend you avoid both solar water and power from an economic standpoint. If you just need a quick shower in the cold season it's far more economical to buy and use a cheap instant water heater. All systems using tanks are not efficient for multiple users since cold water is drawn in and slowly mixes with the remaining hot water. If you want a hot shower on a cold morning forget about the black hose scheme. Likewise for electric - the panels, charge controller, inverter are expensive, and the batteries will need to be replaced every few years. You will never be able to generate or store enough power during the rainy season.

[leela123]

Hi,

Thanks so much for your great comments. ) I read with great interest and researched the whole day on black hose solar heater and by the time cloudhopper replied, I was already sourcing for black polyethylene tubing at the local hardware store. My inspiration came from

http://www.silent9.com/blog/archives/107-DIY-Solar-Pool-Heater.html?/archives/107-DIY-Solar-Pool-Heater.html

Because it is a kuti on monastery grounds, I've been trying to use renewable energy or at least use less energy. The mains are available and from what I've read, it does seem that conventional electricity is cheaper (and more convenient!).

I guess we'll probably just use the heater in winter, and not worth it to install a conventional water heater. I was thinking of just using the kettle to boil water if need be.

Still, I'll try and construct a prototype of the black hose solar heater and test it during my next visit to Chiangrai in winter. We can take baths in the afternoon when the sun is stronger. Still hopeful about making it work I guess. keeping my fingers crossed. If anyone has succeeded with the black hose thing, do buzz me please.

[ksamuiguy]

There is no way to even begin to figure pay back with a solar hot water system. There basicly is No Pay back.

Also no sun no hot water, best way throw a 100 m3 role of PE black pipe on the roof, works like a charm and cheap. Used it on my building in babgkok for years, had hot water 90% of the time (where there was Sun).

[nivram4491]

How much hot water do you need ?

simply lay a roll of black pipe on the roof........ little more expensive use UPVC pipes, make a frame of say 4 pipes, fit on roof or clip to wall, paint black...... better to buy a 'tap and dye' set so you have screwed in joints and not relies on the glue holding only.. pay for itself in a month......... could also do the same but in the loft under the roof get hot up there and will give warm water and no sun damage............ just a cheap idea.

I am trying to find information on UPVC but so far have not found anything relating to hot water use. For hot water CPVC (chlorinated poly vinyl chloride) is recommended.

Does anyone know where one can buy CPVC in Chiang Mai?

I would like to know about threading joints. Is this for plastic pipes? Please tell me more.

[ignis]

I would like to know about threading joints. Is this for plastic pipes? Please tell me more.

Yes,,,,,,, be sure to buy the thick pipes, as they also use a thinner pipe here....... in Portugal the cold water was blue and the hot water white, here both thick and thin tube are blue... the white is even thinner and used for electric cables........ many places here sell T's and bend's with thread already..

Be sure to add a tap cut off in the feed pipe, can also buy here UPVC in line tap with tread s on both ends..

Coil of black pipe even laying against a sunny wall = cheap hot water for the washing machine, far far cheaper than buy a washing machine with a heater

[Benjie]

There is no way to even begin to figure pay back with a solar hot water system. There basicly is No Pay back.

Also no sun no hot water, best way throw a 100 m3 role of PE black pipe on the roof, works like a charm and cheap. Used it on my building in babgkok for years, had hot water 90% of the time (where there was Sun).

How so?

My water heaters in my last house were rated at 1600 watts and were replaced or fixed every couple of years it seemed.

After Air-Con I would expect it to be my biggest energy expenditure.

[ksamuiguy]

If you calculate how long the Shower unit runs, the cost is very little. a shower is about 5 minutes, the water is already warm, by other countries standards.

We find that 80% of the instant water heater failures are due to clogged inlet filters and bad flow switches, mineral build up in the flow switch, very seldom do we find the heating element at fault. That said getting repair parts is very difficult, and there is also a safety issue involved in working on these units.

Now if you are filling a bath tub that's a whole different kettle of fish, for that you need a tank type water heater, and yes it cost a lot to keep water hot!

1/2" black PE pipe the only way to go, no special tools needed and fittings cheap and readily available everywhere so you can adapt to PVC or any other pipe.

..

[Benjie]

If you calculate how long the Shower unit runs, the cost is very little. a shower is about 5 minutes, the water is already warm, by other countries standards.

We find that 80% of the instant water heater failures are due to clogged inlet filters and bad flow switches, mineral build up in the flow switch, very seldom do we find the heating element at fault. That said getting repair parts is very difficult, and there is also a safety issue involved in working on these units.

Now if you are filling a bath tub that's a whole different kettle of fish, for that you need a tank type water heater, and yes it cost a lot to keep water hot!

1/2" black PE pipe the only way to go, no special tools needed and fittings cheap and readily available everywhere so you can adapt to PVC or any other pipe.

..

two showers a day, 4 family members.

Also no chance of getting an electric shock, hot water when there is no electric etc... I'm definitely getting solar hot water next time.

[Dante99]

I would like to know about threading joints. Is this for plastic pipes? Please tell me more.

Yes,,,,,,, be sure to buy the thick pipes, as they also use a thinner pipe here....... in Portugal the cold water was blue and the hot water white, here both thick and thin tube are blue... the white is even thinner and used for electric cables........ many places here sell T's and bend's with thread already..

Be sure to add a tap cut off in the feed pipe, can also buy here UPVC in line tap with tread s on both ends..

Coil of black pipe even laying against a sunny wall = cheap hot water for the washing machine, far far cheaper than buy a washing machine with a heater

The blue pipe here is all cold water pipe, different thicknesses for different pressures. Hot water pipe here is grey and possibly some newer stuff in green.

[ignis]

I would like to know about threading joints. Is this for plastic pipes? Please tell me more.

Yes,,,,,,, be sure to buy the thick pipes, as they also use a thinner pipe here....... in Portugal the cold water was blue and the hot water white, here both thick and thin tube are blue... the white is even thinner and used for electric cables........ many places here sell T's and bend's with thread already..

Be sure to add a tap cut off in the feed pipe, can also buy here UPVC in line tap with tread s on both ends..

Coil of black pipe even laying against a sunny wall = cheap hot water for the washing machine, far far cheaper than buy a washing machine with a heater

The blue pipe here is all cold water pipe, different thicknesses for different pressures. Hot water pipe here is grey and possibly some newer stuff in green.

Thanks.... if I every need to replace know what to look for....... I am sure 9 years ago it was Blue thick or thinner only here.

[onthedarkside]

Thanks.... if I every need to replace know what to look for....... I am sure 9 years ago it was Blue thick or thinner only here.

I do believe the blue pipe (only for cold water) comes in 3 thickness - 8.5 mm, 10.5 mm and 12.5 mm. I always buy the 12.5 mm

[Dante99]

Thanks.... if I every need to replace know what to look for....... I am sure 9 years ago it was Blue thick or thinner only here.

I do believe the blue pipe (only for cold water) comes in 3 thickness - 8.5 mm, 10.5 mm and 12.5 mm. I always buy the 12.5 mm

I used to get 13.5, is 12.5 new?

[Greenside]

Blue PVC pipe is commonly available in 8.5 or 13.5 guage. I don't think the numbers relate directly to the thickness in mm but the the 13.5 is a lot stronger, more expensive and more resistant to UV light too.

[onthedarkside]

Sorry, 13.5 is correct. I always assumed the number related to mm, but I can't say for sure.

[4x4 CNX]

Using "black pipe" solution, is suitable if you take shower in day time until late afternoon, until still have sun and the water still heat by the sun. If you have to take shower in the evening or in the early morning, using the pipe is not suitable, due no have insulation and the water temperature drop quite fast, so need a conventional solar water system with insulated tank ( of course, more expensive solution compare with black pipe ).

[4x4 CNX]

The guy at ABO will only tell you what you want to hear....he is very 2 faced. Check out : http://www.engineo.co.th/index(eng).html

Way better selection with the staff to back up what they sell.

Wow, look like you know him well, any personal experience? Your advice should be important to avoid to go to buy in the wrong place.

[cloudhopper]

Sorry, 13.5 is correct. I always assumed the number related to mm, but I can't say for sure.

The numbers are a pressure rating in kiloPascals/cm2 or similar.

The green pipe is called PEX, uses special fittings and is for hot water.

[cloudhopper]

Using "black pipe" solution, is suitable if you take shower in day time until late afternoon, until still have sun and the water still heat by the sun. If you have to take shower in the evening or in the early morning, using the pipe is not suitable, due no have insulation and the water temperature drop quite fast, so need a conventional solar water system with insulated tank ( of course, more expensive solution compare with black pipe ).

It might be rather inexpensive to drain the hot water from the coils into an insulated tank every afternoon though, without going to the expense of a thermo-siphon type. Requires remembering to do it every 3pm though. Also has the advantage of not being diluted by pressurized cold water over multiple uses.

[nivram4491]

Sorry, 13.5 is correct. I always assumed the number related to mm, but I can't say for sure.

The numbers are a pressure rating in kiloPascals/cm2 or similar.

The green pipe is called PEX, uses special fittings and is for hot water.

PEX tubing cannot be used in applications exposed to sunlight, as it degrades fairly rapidly.

[HullyGully]

The numbers realates to the maximum pressure

1 bar = 14.5 psi x 8.5 etc = 123.25 Cold water