Geothermal passive chilled beam for cooling

Since the summer are getting hotter and hotter, and AC almost becoming an essential now a days especially where i live it is brutal especially this year as it basically went from below constant < 0 to a constant +30c in less then a month. that really hard for the body to adapt so quickly … before you had until August to adapt to +30 now it is +30 by the end of May.

I thought I share . what I use as AC. it is extremely cheap system to operate as it basic design is passive mostly. while i do have geo thermal and I could use that to cool my house … i use the “chilled beam” method but instead of cooling using the geothermal pump I simply use the the geo thermal loop. and run that through my chilled beam. it temperature is almost optimal for it as the chilled beam is suppose to cool at a rate just around the dew point… the cooling fluid come in from the ground at 10 to 15 c and will cool my house to 22-25 c ( depending on the temperature out side. but also I have fair amount of heat being introduce to the house because of solar water heaters) … but anyway it is extremely cheap cooling system to operate as my circulation pump is 49 watts per hour or roughly a 1kw a day to operate to cool 1200 sqf house if it ran 24/7 ( for me it runs 8 hrs aday as the nights are cool still .

on a side note and climate change:
maybe it me as I get older but i just can not handle the heat any more… but does not help the +30 every day and cool at night, where it dew is almost like a rain. and every morning it burns off and back to +30 by 10am again and ~ 100% humidity it like you are living in jungle, yet there no trees around you. but with climate change if it getting tough now… makes you wonder how much tougher it going to be when climate change effects really kick in hard… the current yearly 5 inch hail is scary enough especial when the biggest you might seen before was 1 inch every few years … I chicken wired all my solar equipment last year just in case I get direct hit of 5 inch hail as currently it being dance all round me 20 mile this way or that way

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Thank you so much for sharing this! I already read somewhere you talking about that system and i got curious.
Unfortunately, i have never heard of it in here (Portugal), so it was completely unknown to me.
If you don’t mind, i would like to make some questions:

-Do you have some “schematics” about how its built? or can you make some with fotos included?
-How deep the is the loop burried underground and the lenght of it?
-What type of material are the pipes buried underground and in the rest of the circuit?
-And the Chilled beam is a homemade “radiator with fan (or fanless) system” or was bought on store?
-How is the pump?

Sorry for all this questions but i am interested in this system for my future house but only know it just for heating, not for chilling!

Thank you!

In the UK, there is not so much demand for cooling installs. I have heard of similar setups and at work, my German counterparts have hydraulic plans for integrating their 3 phase GSHPs and using the brine from the ground loops via a plate heat exchanger to provide passive cooling. Not many examples of it over here. Whilst it can work in the right conditions, it does need the pipework suitably insulated & dew point monitoring for silent cooling (where there’s no fan, just a chillled underfloor or panels used). The control strategy also depends on the GSHP used.

Here’s a funky old school flash animation showing how it is done:
Passive Cooling animation

In my personal circumstances, there’s just no room for a GSHP, let alone a passive cooling setup. a mid terraced 110 year old house with a small garden. I have a split AC system to keep one room cool where PCs and a 3D printer are used :grin:

hi there – I use chilled beam for cooling and radiant for heating, hot air rises so it better to be at floor level . cold air falls so it better at the ceiling level where the hottest air is . also it works on the psychology of the human mind … ie if your feet are warm you feel warmer even though the house is quite cooler then what one would consider “warm” and the reverse for cooling if your head feels cooler then you feel cooler over all even though it warmer then what you would call cool…

so if it for heating and not cooling then radiant would be the better choice as heat rises in a passive system

but in either case for me my geothermal pipes - basically if your house is 1200 sqf you need 1200 feet of pipe in the ground ( you can get away with less but I find that is the easiest method)… my pipes are buried at about 7 feet. optimal is +10 feet at that depth the ground temperature is pretty constant . for years I had little issue at 7 feet, but we are having severe droughts lately and the ground is getting quite dry so temperature migration is dropping significantly, under that condition 10 feet would be better… to compensate i probably going to install a drip line above my ground loop at about a 2 foot depth. and start saturating the soil when it gets to dry in the fall…( but I have a massive abundance of water so that not an issue for me and there no cost to it).

so if you are considering GSHP I would ask some local installers for the best depth and length of pipes as your conditions are mostly likely much different then mine… as sure i can hit + 40c in the summer, but I easily hit - 40C in the winter too ( -45c this winter that with out wind chill) so my ground temperature and conditions are different as my soil is normally heavy white loam clay with a high moisture content which is perfect of ground loops
the heat pump i got from china (water to water) cost $500 with shipping 1100 it 7kw version which works fine in my house under it normal condition. in my house but my house is ultra efficient… the circulating pump is justrun of the mill circulating pump. the chilled beam i was lucky, a local beekeer was dismantling bee cooling system m and I got them for basically nothing

Thank you @moojuiceuk and @stephen!
Going to explore and research more since now i know how it works!