Geothermal Aquaponics

[William J Silverthorn]

I have not seen any discussions about GeoThermal water temperature regulation, and I can think of many reasons why it could be a bad idea in an AP system, but I wonder if anyone has found a way to make this work???

most geothermal water temperature regulation set-ups that I have seen would be a more permanent design, and being buried under a widely dispersed area for ensuring a broad area of exposure, which would make it difficult if even possible to conduct periodic maintenance and cleaning out of whatever might clog a closed loop system rich with nitrates and fish solids.

I imagine that it might be possible to incorporate into an AP design, but difficult to design with accessible maintenance in mind that wont harm the efficiency of the design.

if a water pump pipe is routed from a sump tank down a well and back up before taking its regular course into the top of an AP design, then you could use this to regulate the temperature of your fishtank to that of the well water (without mixing the two), and possibly provide a more stable environment for certain designs that might previously have unstable temperature swings at certain times of the year.

thoughts?

[Jim Troyer]

Hey Johnathon! 

Nice write up regarding your greenhouse ideas, they certainly make good sense in some locations.

Today it got to 93 outside and the inside temperature got to 92

The comments regarding your swamp cooler(s) makes me want to comment.  We use coolers here in the Arizona desert, in fact, I have one for my house and it works just great until the dew point gets into the 50s, after that you're just blowing air around because the water doesn't evaporate off the cooler pads anymore.  Adding another cooler will not help cool your green house at all.  Today, your cooler only made a one degree temperature split because the air is saturated.  Don't get me wrong, it would have been much hotter in the GH without the air flow! The point is: you could have turned off the water pump and only used the fan and had almost the same effect. 

I am running my air conditioner currently because the dew point is in the low 60s.  When the dew point is in the 20-30 degree range here; the cooler will make a 20 degree temperature split,  100f degree air in and 80f air out, saves lots of greenbacks...   

We just keep a spare motor, belt and pump on hand since they are so simple to fix, no need to have an extra cooler in the way.  I recommend you spend some time cleaning it up real well this fall, toss the pads, repaint the inside and spray it down extra good with spray undercoating or cooler coating everywhere. Be sure to store it where the rain doesn't get inside all winter too, the rust worms get everywhere if you don't.

As far as keeping your veggies cool, I have mine growing under shade cloth (50%) and they did just fine this summer to 118 degrees.   Tomatoes won't take a blossom after 105 degrees in early June, but we are back to perfect growing weather now... ;-)

All the best,

Jim

[Jon Paul]

 Jim Troyer said 

 Today, your cooler only made a one degree temperature split because the air is saturated.

The Air blowing into my greenhouse from my swamp cooler was 75-76 degrees.  The outside temperature was 93 degrees.  That means the swamp cooler is cooling the air about 18 degrees.  After the cooled air runs into the greenhouse it is heated by the sun to 92 degrees fahrenheit.   If i where to turn the water pump off the swamp cooler would blow 93 degree air into the greenhouse and the sun would heat the greenhouse up to 110 Degrees.  

I definitely need my swamp cooler but i worry that one day the water pump or blower motor could fail.  This would result in cooked plants.  Where i live it commonly is above 100.  On a 100 degree day the swamper cools that greenhouse to about 98.  If the water pump failed, the greenhouse could get to 120 degrees.  If the swamp cooler failed the greenhouse would get very hot.  It failed on me one time at the beginning of the year and i got home to a greenhouse that above 150.  That failure was a result of a GFI tripping.  After investigating the cause of the tripped GFI I found that the problem came from inside the swamp cooler.  I found mineral build up where the pump plugged in.  I cleaned around the mail and female reciprocal which solved the problem.  Since then I have put the swamp cooler on a different circuit that is not GFI protected

 

The second swamp cooler would do two things...

1) On a 100 degree day the greenhouse is currently cooled to 98 degrees with the swamp cooler blowing 78 degrees.  If I had two swamp coolers I predict that i could get the greenhouse to 90 degrees  

2) If one of the swamp coolers failed there would be a second one to cool the greenhouse

There is also another problem....   What happens if the power goes out during the summer. 

I have a neptune controller with 2 power strips.  One Power strip is plugged into a dedicated 20A circuit.  The other will eventually get plugged into a UPS battery back up.  One of the swap coolers and the other vital equipment will be plugged in to the Power Strip that get power from the UPS.   It would be nice to have 5 hours of battery runtime during summer days just in case.  The problem is finding a battery backup that has big enuff batteries.  The best solution that i have come up with is to buy a UPS battery backup and remove the factory batters with a couple of large deep cell batteries.  

[Ian Cameron]

Anyone tried this in the North? I live in central BC, where summer weather is not a problem but -20C - 30C in the winter is. I've looked at the sites around geothermal etc. and have come to the conclusion that a 'stable' feed temperature is the best for warming air or water. What I'm trying to say is its easier to lose heat than gain it, and for Northern areas where fuel costs are so high its better to raise the temp from a stable 57deg @ 8ft to  65deg. that way one is not fighting (fuel wise) large fluctuations in temps. BTW, in my green house at one end I have a home built 3ft dia chimney built in 3 sections 3ft long. The bases are flared to create a venturi effect as they sit over the lower section of straight pipe and slightly above it to allow air movement. On 30C plus days this year, the plastic covering was stressed to the point of tearing if I did not get to open the ends of the greenhouse in time. I wish I had a flow meter for air cause that pipe was vibrating on a good hot day. Now that is convection in motion!