I need some basics here

Discussion in 'Geothermal Loops' started by Krsw, Feb 15, 2016.

  1. Krsw

    Krsw Member

    Solar collectors are quite affordable.... Looking at somewhere in the range of 8-10k for avout 500k btu per day
     
  2. Krsw

    Krsw Member

    Its not even a debate lol, I was considering it a discussion
     
  3. Krsw

    Krsw Member

    New path of thought there, I could quite literally recycle some of the heat... May not be much but every little bit helps
     
  4. Krsw

    Krsw Member

    You are all correct though it sounds great in theory, but developing is a another ball game entirely.... Which is why Im going to a school that offers all I need....
     
  5. Krsw

    Krsw Member

    Correction thats 500 gallon
     
  6. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Ok, my 12 year old daughter won.
    To go from 212F water to 212F steam requires 970 BTUs per pound, 8.33 pounds per gallon, times 50 gallon, makes 404,005 BTUs for a 50 gallon tank.
    The energy required for a phase change is the same if you create a vacuum, it just happens at a lower temperature.

    404 Kbtu stored it will not even last you a day, with a 50 gallon tank. Now if you convert 50 gallon of water to steam, don't you think the tank will blow up? Where do you put the pressure? There goes your vacuum. Why do you think they use salts for phase change storage, and use only the solid to liquid phase change?

    What size solar system are you proposing which delivers 500 KBTU/day in the winter, when you actually need the heat? For $10-15 K? With snow falling occasionally?
    For reference, my $21K solar PV system delivered 14 KWH on a sunny day.

    It appears that you lack the theoretical knowledge, despite your previous notion that you "... know 12 year olds that could do the math you do to hook up a system you had nothing to do with designing. I could teach the average 4th grader to read your gauge and subtract..."

    Indeed it would be an interesting discussion to have on how to store more energy. Unfortunately you lack the theoretical and practical knowledge to contribute to that discussion.

     
  7. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Mel:

    WB

    Trolls?

    Here?

    Students yes.
     
  8. Krsw

    Krsw Member

    It appears your right I was ising the latent heat og ice, so that means I dont need need nearly as big a tank... Even better.. I didnt say solar pv.. It would be more affordable to go with solar collectors.... As it turns out a 100 gallon tank could cover it.. At 817.71kbtu thats enough that I could keep the coil in contact with liquid at all times
     
  9. Krsw

    Krsw Member

    A super heated vapor does not follow the temperature pressure relationship, because it starts at saturation temperature at the given pressure
    No the tank is not going to blow up. Why is it that your refrigeration line doesnt blow up before it reaches the compressor? Why does tje gauge pressure stay the same no matter what? This is something already being done. Take it up with the people doing it....
     
  10. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    If you have 50 gallons full of water, and start turning it into steam (gas), it will expand, thus pressurize a close system.

    The refrigeration line has passed the expansion valve in the heating cycle, thus has lost pressure and is colder.

    You need a much bigger tank, again, phase change storage is only working well with the solid/liquid interphase.

    Don't you understand that you will deplete that heat, those 800+KBTU, on a winter day, within 24 hours. Then what?

    I know you did not talk about solar PV, but even at 14 KWH on a sunny day (at 20% efficiency) gives you an indication how small the solar contribution is, 48 KBTU max. Now account for the efficiency of the solar hot water system. Which tells you much less than 48 KBTU/day.

    That is good for one hour of heat for the house, probably much less, assuming you have only sunshine.
    Now a day of cloud coverage ....

    Do I need to go on?
     
  11. Krsw

    Krsw Member

    Hmmm i got you, yea that is a problem.. Hmmm.... Im not going to give up on it though.... If you could use the liquid to vapor state change it would be pretty cool... My home uses about 65 million BTU per year.... Somebody will find a way to use the vapor state change. It probably will never be needed.... The advent of production small scale fusion reactors is a decade or less away at this point
     
  12. Krsw

    Krsw Member

    Turn the compressor off, the hot high pressure side is condensing, the cold low pressure side is evavorating.... I get it now... Im still not giving up on the idea... There has to be a way to use that liquid to vapor state change.... In my neck of the woods it would be extremely useful
     
  13. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    You need to understand that yes, there is a certain amount stored in a medium, and phase change will release it, but you will deplete that energy. With phase change you will do that slower, maybe it buys you a day with a big tank, then what?
    Unless you resupply that energy, like the ground does, since the heat travels towards the borehole, you will run out of it in matter of days. Phase change is not nuclear fusion, which keeps going for a while. It happens once and that's it.
     
  14. Krsw

    Krsw Member

    I understand that, its not as if I didn't intend to charge it. So back to my original Idea using the swimming pool. Which would work great for heat, but would not work good at all for cooling due to flow rates and a decrease in delta T as compared to geothermal.... And If im going to keep heating the pool with it I might as well have heated the house with it to start with......
     
  15. Krsw

    Krsw Member

    The pool just makes a high volume storage more feasible and usable. The amount of water you would need in the sensible heat range would just take up space.... Perhaps the potable hot water could have a chiller set up like the sortech, air condition by pulling some water off, put it in a vacuum and let it boil off untill it will not boil anymore and send it back at a slightly higher enthalpy...
     
  16. Krsw

    Krsw Member

    Yep lol got to have a few dumb ideas and make a few mistakes befor you really know it or come up with the right Idea.... But I already knew that.... Well thanks for the opportunity to learn a little from you all.... The tank will do nothing.... Boiling water at a low temperature is practically useless for anything but cooling.
     
  17. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    You are welcome...:)
     

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