evaporator single unti or multiple units

Air conditioning, fans, and anything related to keeping it cool, such as insulation. This would include any posts generally discussing how to keep it cool, such as which types of blocks are better insulators.... ideal wall thickness for keeping an A/C house cool, etc.

Moderators: Sometimewoodworker, MGV12, BKKBILL

evaporator single unti or multiple units

Postby arranp » Sat Nov 22, 2014 7:17 pm

When using an central earth loop condensor is it better to use a central evaporator unit with duct work or an evaporator unit in each room ?
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Andyfteeze » Wed Nov 26, 2014 6:17 pm

cental earth loop condenser? WTF is that!!!!
Evaporative aircon, I understand but CELC? new to me and I suspect many others, lol.
Man , you are chasing the most esoteric forms of energy looking for savings when all you do is spend ten times more than just conventional stuff.
I think the biggest bank for your buck is trying to lower your energy usage . Your kwhrs per month is HUGH. :lol: Cut this in half and you save 3000b, this is something you have checked out? :shock: talk about looking for band aids to cover a festering sore, hahaha.
Andyfteeze
 
Posts: 394
Joined: Sat Aug 30, 2014 6:29 pm

Re: evaporator single unti or multiple units

Postby arranp » Wed Nov 26, 2014 6:39 pm

conventional air con units use an air condensor, a geothermal system uses an underground loop of water connected to a condensor, it dumps the heat under the ground which is cheaper to cool than dumping the heat into the outside air.

look at the bottom right of this image
Image

Image

The evaporator units are inside the house, you can use a central evaporator, blower and ducting to force the cooled air around the house, or place separate evaporators / blowers in each room ( rather like air con units ) and connect them back to the central condensor / compressor.

a traditional air con unit is much the same as a fridge except for the fans both have : compressor -> condensor unit/coil -> expansion valve -> evaporator unit/coil

only difference is the condesor /coil in a standard fridge or air/con unit dumps the heat to air, it cheaper to dump the heat to a cold loop of water under the ground (about 2m under the ground) this technique is called geothermal cooling.
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Andyfteeze » Thu Nov 27, 2014 9:54 am

Ok, how about you implement it and then tell me how much it costs and how hard it was to get working. Then I will be your fan. :lol:
Seriously, in theory it sounds good. I have thought about a similar setup. the temp 2m below is about 18c.
An alternative is to use your swimming pool as a sink. ( see I have been there, lol)
problems i can foresee.
Cost. is it so effective it will reduce costs by a big margin? Is it expensive to setup?
Effectiveness. If your setup is large enough above ground, you could overwhelm the heat sink around the below ground coils/tank to create a hot spot which negates the purpose. It needs a lot of investigating to see what the energy equilibrium points are and the energy spread needed. Only then can you estimate the sizes above and below ground which feeds into the costs. Wish you luck with that. For a fee, I can conduct the experiments required and all the calculations for you. It may take two years to do it comprehensively that is to take into consideration seasonal fluctuations. :shock:
Points that I think you are missing on your search are 1/ are your appliances energy efficient 2/ have you built an infrustructure around your self that sucks up lots of energy? If your paying 7000b per month, there is your answer. Maybe cheaper in the long run to cut the waste. :oops:
Probably not what you want to hear :cry:
Andyfteeze
 
Posts: 394
Joined: Sat Aug 30, 2014 6:29 pm

Re: evaporator single unti or multiple units

Postby fredlk » Thu Nov 27, 2014 10:02 am

Andyfteeze wrote: the temp 2m below is about 18c.

Not where I live. The water coming out of my 49 meter deep borehole arrives at the surface at 24 degrees Celsius.
In the cool season you'll be lucky to get down to a temperature of 22 degrees at 2 metres below the surface.

This stuff doesn't work in the tropics!!! :roll: :roll:
User avatar
fredlk
 
Posts: 5879
Joined: Tue Apr 07, 2009 3:11 pm

Re: evaporator single unti or multiple units

Postby arranp » Thu Nov 27, 2014 10:04 am

Andyfteeze wrote:Ok, how about you implement it and then tell me how much it costs and how hard it was to get working. Then I will be your fan. :lol:
Seriously, in theory it sounds good. I have thought about a similar setup. the temp 2m below is about 18c.
An alternative is to use your swimming pool as a sink. ( see I have been there, lol)
problems i can foresee.
Cost. is it so effective it will reduce costs by a big margin? Is it expensive to setup?
Effectiveness. If your setup is large enough above ground, you could overwhelm the heat sink around the below ground coils/tank to create a hot spot which negates the purpose. It needs a lot of investigating to see what the energy equilibrium points are and the energy spread needed. Only then can you estimate the sizes above and below ground which feeds into the costs. Wish you luck with that. For a fee, I can conduct the experiments required and all the calculations for you. It may take two years to do it comprehensively that is to take into consideration seasonal fluctuations. :shock:
Points that I think you are missing on your search are 1/ are your appliances energy efficient 2/ have you built an infrustructure around your self that sucks up lots of energy? If your paying 7000b per month, there is your answer. Maybe cheaper in the long run to cut the waste. :oops:
Probably not what you want to hear :cry:


earth loop ( water )
6ft deep
45 - 70 degrees
high density polyetherlene pipes - earth loop system - all joints are heat fused

vertical loops 45 - 90 mt in depth - 1 bore hole per ton of equipment capacity
horizontal loops 45 - 90mt in length @ depth of 2 meters - 1 trench per ton of equipment capacity

apparently its 25% of the cost to dump the heat through a earth loop condensor compared to an air condensor, due to less kWh needed.
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Andyfteeze » Thu Nov 27, 2014 10:39 am

ok, are your assumptions based on 8*c underground as in your drawings? thats the first problem as it seems it was designed outside of thailand.
its a big excavation, you factored that cost? Have you done the necessary research on the size required and ability of the earth to absorb that amount in the available area? that 25% suddenly looks way optimistic. That plan looks to me like something that has to be scaled up to be of any benefit. 10% of FA is different to 10% of huge. Have you just taken the figures at face value without doing any actual research?
I know I bang on at you, but I am just playing devils advocate. When I shut up, you are on a winner. :D
Andyfteeze
 
Posts: 394
Joined: Sat Aug 30, 2014 6:29 pm

Re: evaporator single unti or multiple units

Postby arranp » Thu Nov 27, 2014 10:43 am

Andyfteeze wrote:ok, are your assumptions based on 8*c underground as in your drawings? thats the first problem as it seems it was designed outside of thailand.
its a big excavation, you factored that cost? Have you done the necessary research on the size required and ability of the earth to absorb that amount in the available area? that 25% suddenly looks way optimistic. That plan looks to me like something that has to be scaled up to be of any benefit. 10% of FA is different to 10% of huge. Have you just taken the figures at face value without doing any actual research?
I know I bang on at you, but I am just playing devils advocate. When I shut up, you are on a winner. :D


you banging on is most welcome, I have no one else to talk to :-( ....

all taken at face value thus far. I need more research and calcs. my contractor is a friend so can drill me a few more holes if needed, I'm not sure the cost of the pipe.
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Andyfteeze » Thu Nov 27, 2014 11:03 am

Ok , just some basic research
"A GHP system was installed to a building at Kamphaengphet, in October 2006. This system was experimentally used as a
space cooling system for 17 months, till March 2008. Temeprature changes in the heat exchange borehole, at inlet and
outlet of heat pump, and of room and atmosphare, and electricity comsumption were measured. The results of this
experiment are summarized as follows;
- 85% of temperature increase in heat exchange well was recovered in ten days after stopping operation.
- A successive operation of the system causes temperature increase in the heat exchange well even at the bottom hole, but it
recovers in a week after operation has stopped.
- No long term subsurface temperature increase occurred over a year of operation.
-
For effective cooling of the room, proper setting of heat pump operation is necessary. Difference between maximum and
minimum temperatures of the inlet fluid should not be bigger than 5K.
- With a proper setting of operation, room temperature was kept from 23 to 28
o
C, while outside temperature was from 30
to 35
o
C during the period.
- The electricity consumption rate was around 0.6 kW with proper settings of operation.
- The COP value for this stable operation period was around 3.
Thus applicability of GHP in Thailand is confirmed by this experiment. For more effective utilization with better cost
performance and COP, some adjustment of the system would be necessary.
ACKNOWLEDGEMENT
This study has been conducted by international collaboration of AIST Japan and DGR, Thailand.
REFERENCES
Yasukawa, K., Uchida, Y., Taguchi, Y., Tenma, N., Muraoka, H., Buapeng, S. and Nguyen, T. H.,
(
2006)
.
Possible utilization of ground-
coupled heat-"
Seems there are limitations. the bore holes do heatup. The bore holes may also be below the water table. This may be good or may be bad.
Why am i DOING YOUR RESEARCH? :oops:
Andyfteeze
 
Posts: 394
Joined: Sat Aug 30, 2014 6:29 pm

Re: evaporator single unti or multiple units

Postby arranp » Sat Jan 10, 2015 8:00 pm

Came across the same document, this link shows study:
http://www.geothermal-energy.org/pdf/IGAstandard/Asian/2008/8_18_yasukawa.pdf

They summized the following:

- With a proper setting of operation, room temperature was kept from 23 to 28*C, while outside temperature was from 30 to 35*C during the period.
- The electricity consumption rate was around 0.6 kW with proper settings of operation.


a single conventional split air con unit uses 1.5 kW upwards, the Geothermal Heat Pump (GHP) (as per study) uses 0.6kW, the GHP consumes less electric than the split air con unit.

the only other thing to do is work out the cost of installation and maintenance compared to conventional split air con units.

however, still not satisfied that Geothermal is the way to go in Thailand, heres a thai company promoting the use of geothermal http://led-gpi.com/solarpower/geothermal-cooling.html

I understand these Geothermal systems are only used in the daytime when the ambient temperature is above the subsurface temperature. During the night time it would seem more appropriate to use a "house fan" which draws the cooler outside air into the house space and out through the attic.

http://islandcooling.com/blog/hawaii-island-life/proper-air-ventilation-relief-from-the-heat
Image

However, the "house fan" system relies on the doors and windows being open, whilst the "geothermal heat pump" system relies on the doors and windows being closed. Not sure I could be ars**d going round opening and closing the doors and windows every day or would want a system that requires me to do that. ummmm.
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Roger Ramjet » Sun Jan 11, 2015 9:38 am

arranp wrote:however, still not satisfied that Geothermal is the way to go in Thailand, heres a thai company promoting the use of geothermal

arranp,
Everything you've posted is hypothetical and you haven't read the geothermal thread. I posted a university study done in Thailand on the use of geothermal cooling. I also posted the photos, which included the size of the land needed, the pumps needed and exactly what they used along with all the technical details. The size of the land was staggering, the cost of the materials staggering, the cost of digging and recovering the area staggering and the cost savings were minimal. Just one "leak" in the underground coils and the cost of finding it far outweighed any "benefit", if there was any at all.
If you wish to hypothesise the whole time, perhaps you should post the plans of your build, size of your land and especially your budget. There is no such thing as a green house. Thai builders have limited knowledge of construction as it is and have absolutely no/little knowledge about science. If on the other hand you're posting science, perhaps you'de like to start a new thread as I have access to many university scientific studies that are not on the mainstream (accessable to the public) which I would be willing to share, without fee, but at this stage I do wish you would stop guessing about topics that have already been answered.
User avatar
Roger Ramjet
 
Posts: 5284
Joined: Tue Apr 27, 2010 12:55 pm

Re: evaporator single unti or multiple units

Postby arranp » Sun Jan 11, 2015 11:12 am

Roger Ramjet wrote:
arranp wrote:however, still not satisfied that Geothermal is the way to go in Thailand, heres a thai company promoting the use of geothermal

arranp,
Everything you've posted is hypothetical and you haven't read the geothermal thread. I posted a university study done in Thailand on the use of geothermal cooling. I also posted the photos, which included the size of the land needed, the pumps needed and exactly what they used along with all the technical details. The size of the land was staggering, the cost of the materials staggering, the cost of digging and recovering the area staggering and the cost savings were minimal. Just one "leak" in the underground coils and the cost of finding it far outweighed any "benefit", if there was any at all.
If you wish to hypothesise the whole time, perhaps you should post the plans of your build, size of your land and especially your budget. There is no such thing as a green house. Thai builders have limited knowledge of construction as it is and have absolutely no/little knowledge about science. If on the other hand you're posting science, perhaps you'de like to start a new thread as I have access to many university scientific studies that are not on the mainstream (accessable to the public) which I would be willing to share, without fee, but at this stage I do wish you would stop guessing about topics that have already been answered.


posted my build story here http://www.coolthaihouse.com/forum/viewtopic.php?f=3&t=4862
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby arranp » Sun Jan 11, 2015 11:24 am

came across this article, this chap has cools his house by convection only, this seems interesting and "very green" at first glance.

Passive Solar House in Tropical Areas http://www.kotaronishiki.com

In our case, When the outside temperature is about 33 degree Celsius, without the second board, the outside part of the wall becomes 43 degree Celsius and the inner part of the wall become 35 degree Celsius at 3 pm.

With the second wall, inner wall is 28 degree Celsius. This means that the wall maintains night time temperature. Remarkable !!!.


2nd roof for convection air flow
Image

night time cold store
Image

Image

Image
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby arranp » Sun Jan 11, 2015 11:27 am

arranp wrote:
Roger Ramjet wrote:
arranp wrote:however, still not satisfied that Geothermal is the way to go in Thailand, heres a thai company promoting the use of geothermal

arranp,
Everything you've posted is hypothetical and you haven't read the geothermal thread. I posted a university study done in Thailand on the use of geothermal cooling. I also posted the photos, which included the size of the land needed, the pumps needed and exactly what they used along with all the technical details. The size of the land was staggering, the cost of the materials staggering, the cost of digging and recovering the area staggering and the cost savings were minimal. Just one "leak" in the underground coils and the cost of finding it far outweighed any "benefit", if there was any at all.
If you wish to hypothesise the whole time, perhaps you should post the plans of your build, size of your land and especially your budget. There is no such thing as a green house. Thai builders have limited knowledge of construction as it is and have absolutely no/little knowledge about science. If on the other hand you're posting science, perhaps you'de like to start a new thread as I have access to many university scientific studies that are not on the mainstream (accessable to the public) which I would be willing to share, without fee, but at this stage I do wish you would stop guessing about topics that have already been answered.


posted my build story here http://www.coolthaihouse.com/forum/viewtopic.php?f=3&t=4862


do you mean this one ?

Re: evaporator single unti or multiple units
Postby arranp » Sat Jan 10, 2015 8:00 pm

Came across the same document, this link shows study:
http://www.geothermal-energy.org/pdf/IG ... sukawa.pdf
arranp
 
Posts: 163
Joined: Wed Jan 19, 2011 8:45 pm

Re: evaporator single unti or multiple units

Postby Roger Ramjet » Sun Jan 11, 2015 12:18 pm

arranp wrote:do you mean this one ?

No, that was just one of a large number of experiments conducted in Thailand over a period of 40 years. Most, if not all were looking at using geothermal heat exchange to generate electricity. There were four phases to the experiments and all were restricted by seismic actvity, deapth of bore holes (some over 2,000 metres) and the location of "hot springs". Which is the reason I asked about area and Phuket is not an area regarded in great stead as far as geothermal transfer is concerned unless your land is sitting over this. http://www.thehotspringbeach.com/
And for air conditioning using underground piping you do not have enough land.
As far as your photos are concerned regarding the "green house" you're living a pipe dream, the inside temperature will always be the same as the outside temperature unless you use all the best materials (superblock), Colorbond roofing, insulation and double glazed glass (not the cheap Chinese version)..... but none of that is "green" it's just best building practice and has been used for years. All of this has been extensively covered in other threads so why don't you ask all the questions on your building thread? That way at least builders can point you to a thread that has already been written instead of hypothetically guessing on threads that have a specific designation. IE Solar Power has now two threads and one has basically nothing to do with solar power but guesses.
User avatar
Roger Ramjet
 
Posts: 5284
Joined: Tue Apr 27, 2010 12:55 pm

Next

Return to cooling systems

Who is online

Users browsing this forum: Google [Bot] and 0 guests