Backyard Aquaponics
A place to discuss aquaponics

I'm a little cross ,, not angry , about this CRUD. I;ve taken pics of two normal drinking glasses being filled from the same warm water container , I've taken Pic's of the burial of one and insulation of the other ,, I've taken pic's of the time ( clock).....,
I say ,,there will be a substaintially warmer ABOVE ground glass within 30 minutes???

Any bets?

While i would like this topic to continue i think that rupe is right that it needs its own thread and maybe we could keep this one for my system (selfish i know).

However i just cant resist making a few comments.

I agree with rupe in that why would a manufacturer of HWS spend more money on making a tank that was `ground proof' when they are not the ones who end up paying the energy bill, it is us the consumers that do.

as for the antartic base there may be many reasons they did it this way. It seems that it is built on rock, not soil, which may actually be very difficult to have `dug in' a base due to machinery availability and cost. You might also find that as it is a protected place the restrictions on digging in might prevent this also.
not burrying igloos might be something to do with the fact that the digging into permafrost may have been too hard to do with the tools they had available.
there are many earthburmed or earth covered houses around the world showing much less heating/ cooling energy due to the thermal mass that large amounts of earth provide.
This is due to the diurnal temperature of the air, as it is a very poor insulator when moving. The earth stays a much more consitent temperature than that of air, especially in areas of desert etc. One has only to look at the town of coober pedy, a town underground in order to maintain a constant temperature for living. The reason they can do this is they have the resources available to dig you a big hole in ground that will support this sort of living.
The principle of geothermal heatpumps can be raised to show proof of this. In areas where ambient temps are low (either night or day), pipes are sunk into the earth or under a large body of water in order to exchange heat into a fluid medium that is then pumped up to a house where the heat moves out of the tubes to the colder air.

As for my little settup, the wind chill in esperance is quite large, and having a tub exposed to that would surely reduce temp more than having it out of the wind. I could have insulated it with a paper adobe type medium which would have provided a great biomass to keep the temp stable, but hey i am a bit lazy and was pushed for time.
Also the stand i got for free would not have allowed for a gravity fall if the tub was above the ground.
So i guess i am saying that my tank was put in the ground so as to allow for ease of setup as well as removing a large amount of surface area which the wind could suck heat out of. I hope to continue this discussion on another thread as biomass and geothermal heat is another one of my intrests.

ROFLMAO ,, about 20 minutes more on my test run will show truth.

tick tick tick..

Couldn't wait ,, ABOVE ground glass warm I mean nice and warm ,, buried glass already very cold to the touch.
I'll leave it at that on this thread.

Cheers


'

I have no doubt that an insulated glass will cool down quicker in you experiment. I think that the fact is on a very small scale and you are using earth only cm thick will prove nothing other than you have put something warmer into a cooler medium and heat transfer has occured. Now if you put that glass out in the cold air blowing around it, lets say 15-30 knots we might see some different changes. Have you ever been into a mine shaft, at about 10 meters you start to notice that it does not matter what the ambient temp is on the surface, it will remain a consitent 25 or so degrees. It also gets warmer as you get much deeper, (see geothermal ideas) Chappo i love your enthusiasm for this topic and i hope that we continue it, but your little glass experiement wont sway the arguement for me, I hope that your insulated glass does win, cause otherwise insulation companies might loose out business to people with shovels.

i'm somewhat amused , Point was proven and now you wish to change the parameters.
Acually there was some wind speed , but let's face facts ,, the above ground container remained warmer,.
25 meteres down ,, anyone have their tanks buried at that depth??? And i doubt temp was 23C
I concede that a tank buried in Earths MANTAL would pre steam your fish ,, that is NOT what is being discussed here.

next experiment will be 2 X 50 litre buckets ,, one buried at say 50 cm ,, other above ground and insulated ,, I expect result will be the same ,, but take a little longer.
Anyone want more parameters changed before ONCE again being proven WRONG ,

I note, I was welcomed to continue this forgone conclusive experiment , within this thread.

ah yes, the next experiment will prove the same. Now all i say it that i look at the nice little extra known as insulation, as with my little pun above you will see that i conceed that manufactured insulation may well provide better heat reflective properties, but as you will note from the above discussion, i was never willing to spend money on insulation, therefore by my parameters some insulation from the earth would be better than none. However I wish to see the data from this experiment, i hope that you will try different types of insulation as members may benefit from your research on what type they should spend their money on if they are indeed willing to spend anything. I am happy for you to post the results on this page chappo, keep up the good work, and remember...the truth is out there.

Gee its hard to talk nice sometimes.....

Chappo - If you read my post - I was talking about the ground @ 1 METER DEPTH (IBC depth).

You have people telling you FACTS that we know from EXPERIENCE doing what we are doing.

You cant seem to take it as it is.

I have two AP systems, one is an IBC above ground, and one was an IBC below ground (before the addition of more tanks) The below ground one in summer was 8 degrees cooler in the middle of the day, compared to the above ground one. Now in winter the below ground system at 630 am in the morning is 7.0 degrees warmer @ 16 deg c, compared to the above ground system @ only 9 deg c.

This is the difference between being able to keep a fish species to growout size - or loosing them.

Also due to radiation, the above ground system has a 8 - 10 deg c difference in temperatures through out the day. The below ground system (although having a bigger thermal mass skews the results) varies 0.5 degrees c per day.

I dont need any silly bury a 50 litre bucket in the ground and see what happens experiments, I have already done it with 4000 litres of water.

We have done it - you havent, so you shouldnt be running around trying to debunk everyones FACTS.

GRR you've made me late for work AGAIN!

Sorry Wolfy, see you on Saturday arvo

Ahh Chappo...... why is it that "it's above ground"???



Too important points in that little sentance Chappo...... "rock on the coast"....

I'd be guessing (substantively, Id say) that the rock is very hard, by nature, and VERY COLD... by centuries of EXTREME COLD .... i.e the rock has an ambient temperature that's probably very close to that of the air anyway... even allowing for seasonal fluctuations...

The fact that it's VERY HARD... would have meant shipping a complete drilling rig, probably with diamond cutters.... or the use of lots of explosives.... to dig holes.

Given when the base was built, number of available personnel, costs of shipping.. and available season length to do the installation....

Then I'm not the least bit surprised that they didn't bother about any possible thermo-efficiencies.....

Just plonk it down, bolt/strap it down.... and HEAT it.... they have to HEAT everything anyway... and shipping down/installing a deisel unit to heat quarters and water etc is a darn sight easier and cheaper... and more servicable .... than burying the stuff for any efficiencies.

Considering the likely narrow range of temp differential between the "rock"/earth and the air... it probably wouldn't have been worth it anyway

Apart from which OBO and others in the DESERT are a completely different set of thermodynamics...... centuries of HOT influences.... and a fairly stable HIGH ambient ground temperature....

As proven by the case of places like Cooper Pedy.... caves etc....

Apples are apples Chappo.... and oranges are oranges.... science doesn't mix apples and oranges into the same experiment.... you just can't get results that allow proof of your "hypothesis" that way...



In other words a "proposition", for the sake of arguement but one that needs to be tested to see if proof can establish it's validity...... a "conjecture", until proven otherwise... one way or another....

And in order to prove it, you need to keep the variables the same for both experiment...

i.e
you need the same sized/dimensioned containers
... to ensure the results are consistant (obviously)

you need to fill them with the same liquid with the same capacity
.... to ensure the results are consistant (obviously)

you need the ground and air temp to be the same
.... to ensure the results are consistant (seemingly obviously)

you need to run the experiment for same length of time for both scenarios
.... to ensure the results are consistant (obviously)

you need to run the experiment for sufficient lenght of time
.... to see if the results are are a straight line projection, or if time alters the result in some possible "exponential" trend

To my mind Chappo... you need to conduct at least 8 experiments.... to obtain reliable data

(1)
Two buckets, one uninsulated, the other insulated... in the ground... for a set time period
... to demonstrate the comparative influence of the insulation in relation to thermal properties of the ground

(2)
Two buckets, one uninsulated, the other insulated... in the air... for a set time period
... to demonstrate the comparative influence of the insulation in relation to thermal properties of the air temps

(3) & (4)
Repeat above steps with different sized containers...
... to demonstrate the comparative influence of the thermal mass of water volume in relation to thermal properties of the ground and air

(5), (6), (7), (8)
Repeat above steps over a longer, greatly extended period of time
.... to see if any measured effects "plateau"... or trend directly or exponentially over time

You may find that you get certain results for a "small" volume of water... but significantly different results (over the same time period) for a "arge" volume of water...

Or that your results vary significantly over time....

You cant insulate one bucket (apple) and put it in the air... and put another uninsulated bucket (orange) in the ground....

And compare "apples" and "oranges".... it just doesn't work that way.... tooo many different variables.... thermal properties of the insulation, thermal properties of the different base media (ground/air), and different base temperatures

Let only the "possible" thermal properties of either over time.... or over capacity....

Yep Rup,
I've worked at Mawson and I can assure everyone that the rock is indeed VERY hard.

If the point of burying the tank were really to Insulate a heated amount of water, then that would not be an efficient way to do it. But as most people who have been burying tanks seem to say, it is for the thermal mass (not the insulation.) The ground is actually not a very good insulator beyond it's own temp. However, I've found that having my big tank in ground is very good for keeping a more stable temp (keeping the water a little cooler in the heat of summer and keeping the water mass warm enough in the coldest part of winter to keep the fish alive without added supplemental heating.)

If you go with fish that like your regions average ground temp, then burying the tanks makes sense. If you are going with fish that want really warm temps and your average ground temp is much cooler than that, you are better off with insulation no matter where the tank goes.

So how is the system doing Wolfy?

Wolfy , I agree all this does not belong in your thread ..... Mods ,, could you please moove this into my " two system one cold one hot NO compromise thread".

Thanks to wolfy for letting us ( mainly me )wreck his thread ( although temporarily).

Yay for TCL

I have been monitoring the temps in my shed and fish tank since I started. The graph pictured is of this data.
The left hand axis is temps in degrees C and range from zero to 40 degrees.
The base axis is dates and ranges from 22/09/07 to 10/06/08.
I have been a bit slack from time to time and didn't check the thermometer every day - this is why the dots are not often connected.
I have however recorded ALL maximum and minimum temps during that time as the thermometer is an electronic one which records such things. The tank max and mins are the blue and green dots while the room/shed variations are the orange and red dots.
While I am having temps lower than I would like it is very clear to me that having the tank buried in the ground is of IMMENSE value as far as temperature stability is concerned. Quite frankly I can't see how this is not a good thing!

well done Jim, shows things very clearly