Would strongly advise the 10 baht option as a cold drink could to be a rather costly experience.

one fairy tale after the other in this thread!

if your LG 18k btu/h uses 5.2 kWh it must have been produced pre-World War II. even a 20 year old 18k unit does not use more than 2kWh in cooling mode.

Used an online calculator to convert BTU to kWh, that's what it came out with. Both are units of energy, one measures energy to heat a pound of water by 1°C, the other is 3.6MJ, one unit of household electricity.

I am no expert, just giving the OP my experience.

Air conditioners don't heat water.. it isn't actually producing heat or removing it, it's just moving it around (from inside to outside), which is much more efficient than producing it.

Hence Air conditioners have a so called '(S)EER' rating (name and definition have changed a couple of times) but basically it's the 'Energy Efficiency Rating' factor that you have to work in to convert from BTU (moved) to Actual power usage.

http://asm-air.com/airconditioning/seer-vs-eer-what-is-seer-what-is-eer/

(edit) This is why that huge air conditioning installation in your house is using about the same power as your electric kettle...

Air conditioners don't heat water.. it isn't actually producing heat or removing it, it's just moving it around (from inside to outside), which is much more efficient than producing it.

Hence Air conditioners have a so called '(S)EER' rating (name and definition have changed a couple of times) but basically it's the 'Energy Efficiency Rating' factor that you have to work in to convert from BTU (moved) to Actual power usage.

http://asm-air.com/airconditioning/seer-vs-eer-what-is-seer-what-is-eer/

(edit) This is why that huge air conditioning installation in your house is using about the same power as your electric kettle...

hold your horses mate! some airconditioners do heat water, e.g. the one below who's modification and installation i designed to heat my pool. i refrain to comment on "energy of huge aircons and electric kettles" to avoid any embarrassment

note: besides moving heat each airconditioner also generates heat like an electric bulb who's energy input is not only generating light but also heat. the two fan motors and especially the compressor generates heat (behind the back of unsuspecting laymen).

Yeah I wasn't really talking about your industrial sized equipment, but fact remains a 18,000 BTU airconditioning unit uses about the same when running full-blast as a kettle (1.5 - 2kW)

The loss due to inefficiency (heating, insulation losses etc) are all accounted for in the (S)EER.

Nice modification, though. Any schematics on what you did exactly? Looks like you added a water pump and a heat exchanger to the return pipe?

But a kettle only has to run for about 10 minutes - insulation is a bit better than in a home. Once water to boil it uses almost nothing even if still plugged in. That is not the case with an air conditioner (in other than winter) and they will always be running fan if in cooling mode and have to cycle much more often.

The way to save on air conditioning is to set temperature a bit higher - unless doing physical work 25c is not really needed for most people to be comfortable - I find setting at 28c is fine for computer/tv/reading room activities.

this is our cooling system ...

Yeah I wasn't really talking about your industrial sized equipment, but fact remains a 18,000 BTU airconditioning unit uses about the same when running full-blast as a kettle (1.5 - 2kW)

The loss due to inefficiency (heating, insulation losses etc) are all accounted for in the (S)EER.

Nice modification, though. Any schematics on what you did exactly? Looks like you added a water pump and a heat exchanger to the return pipe?

the method is a rather simple one. the only problem was to find a contractor to carry out the work (which was done to my full satisfaction).

the heat exchanger takes the heat from the aircon and heats up by recircling (using a ½hp pump) the water of the overflow tank which works as a buffer from where it is pumped to the pool. so basically the aircon works water cooled when pool heating is required. the aircon cools at the same time my (enclosed) pool area. a sensor switches from water cooled to air cooled (triggering the condenser fan) when pool heating is not but cooling of the pool area is required.

the installation was some years ago only a stop-gap solution. in the meantime i installed solar roof panels through which pool water is pumped when heating is required. these panels were not available then.