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Peer review please...

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Mark Eatherton
Mark Eatherton Member Posts: 5,853
Wallies, I have been working on this idea for nigh on 20 some years, and I want to get some feed back from my fellow Wallies to make sure I am not too far off in the weeds.



Here goes. Snowmelt is viewed by environmentalists as a terrible waste of natural resources. They don't care that there is an associated reduction in slip fall hazard law suits, or reduction in the use of snow melting chemicals, to say nothing of the documented floor maintenance cost reductions. They don't like it.



What if the SIM slab became a solar powered low temperature collector/heat emitter (think heat rejection into the night sky).



It would maintain the slab at a minimum of 35 to 40 degrees F. My thinking is that the slab will generate more energy than it consumes. It will benefit not only from the solar thermal gain component, but also the ambient air energy potential, which is huge.



It will obviously need to be matched to a load. If that isn't possible, then the production of the slab is stored in either VBH thermal batteries, or sub surface Thermal Storage batteries.



My goal would be to eventually gain tax credits for proven use to availability ratios (Continuous COP) of 3 to 1. Using WSHP makes that a snap.



I'm thinking it could be 2 stage. Stage 1 is a direct exchange to any load that needs it and can use it at a given temp (I've seen 140 deg. F stagnated temperatures on slabs in middle of summer), including but not limited to DHW pre-heat, swimming pools, spa's and hot tubs, and even some space heating loads. When it is too cool to use for any of these loads, then the WSHP kicks on, drawing the slab temp lower (thereby increasing its "in flow" delta T) and takes it to one of two operating temperatures, depending upon the mode of operation. If it is in "water production mode", then its surface will be drawn down low enough to condense, but never less than 35 degrees F where frost might form.



If the slab does get called upon as a snowmelt surface, then all energy draws off of the slab stop.



If it is operated in the "No Water Production" mode, then the slab is never drawn to within more than 5 degrees above the dew point. But again, never less than 35 to 40 degrees F, unless doing so naturally. Dew point could be monitored and calculated know the rH and ambient temperatures. This would control the fluid temperatures being run through the slab.



The GREEN advantages of the system should be fairly obvious.



1. Using energy that is free for the taking (solar and ambient temperature differential), thereby,



2. Reducing the heat island effect and hence forth reducing the effects of alleged global warming.



3. Reductions of thermal stress typically associated with significant structural degradation of concrete slabs. Swimming pool decks would actually feel cool to the human touch (thinking bare footed children running around a swimming pool)



4. Controlled production of water (humidity) further reducing the potential of "green house" effects associated with alleged global warming. (this is not a conversation on wether or not its real or perceived. Climate change is for real)



5. Significant reductions in carbon foot printing of all connected loads.



6. The previously touted benefits of snow melting systems.



7. Can act as a heat rejection system (active or passive) at night for the production and storage of chilled water to handle peak loading conditions for buildings using radiant cooling. Night sky re-radiation through the use of proper colored concrete dyes has been shown to enhance absorption and rejection of thermal energy.



Feel free to chime in on any benefits I might have missed.



All of the components necessary to make these systems work are already available off shelf. I am going to generate a drawing in the next few days depicting how all of these components fit together to make this thing work.



I welcome your thoughts, positive or negative.



By the way, this is not a new concept, and if you or someone you know has deployed this technology before, please contact me. We need all the powder we can get for the legislative bullet to get credit for the cost of the components necessary to make this idea work. I think I remember something about Mario Andretti heating his olympic size swimming pool for free using his SIM driveway. I'm sure there are more of them out there…



Thanks for taking the time to read this lengthy submission, and thanks in advance for your comments.



ME
It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.

Comments

  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
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    Solar snowmelt

    Maybe just a darker color change of the concrete would pick up enough energy to at least loosen the bond between ice, and concrete. The snow does not need to be boiled off, and the snow shovel will still be needed.

    The production of concrete uses large amounts of heat-whether from natural gas, or burning recycled tires!

    Anything we can do to prolong the life of the concrete we have, will save energy. Snowmelt systems will prolong the life of concrete, by reducing the need for brute-force ice chipping, or or the application of concrete-destroying salts.--NBC
  • Rich_49
    Rich_49 Member Posts: 2,766
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    Mark

    This is something that I have given much thought to also . I have also thought of and others on the east coast have started use Black roofs as a sort of solar collection assembly . Sheath the roof with panels if you will . 

    While climate change is certainly a real phenomenon I view it as a very hot political potato and it may be best left out of the description as those who would discard or not take seriously because of the wording , and the Green / Passive guys will or will not accept it . They would rather stuff a house full of insulation , make it a 10,000 BTU per hour design house then install 23,000 BTU worth of ductless mini splits and call it efficient . Proceed to tell us our stuff is too expensive when in fact the only guys they are familiar with or worked with do not know what we know . I would rather view it as conserving our resources for future generations while not contributing to the heat ceiling effect , Co emissions and the like .

      I must go out to earn now but am interested to see where this goes .  
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Xlath...

    Rich, check out Xlath.com They make what you want. Can be used as a roof or a radiant ceiling/wall assembly.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Sal Santamaura
    Sal Santamaura Member Posts: 529
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    I'm not even close to being a peer...

    ...Mark, but am curious about your post.  Number 2 on Its list of advantages includes:



                 "...reducing the effects of alleged global warming."



    Implicit in your use of "alleged" is rejection of global warming's reality.  The overwhelming preponderance of scientists (other than those working for fossil fuel corporations) who've evaluated the data agree not only that temperature integrated over our planet's surface has been rising and continues to rise at an ever increasing rate, but that the clear cause is human activities releasing CO2 into the atmosphere.



    If you don't accept us as the cause of global warming, how can number 5 in the list



                 "Significant reductions in carbon foot printing of all connected loads."



    be an advantage?  :)
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Hi Sal...

    What I DON'T want this discussion to do is to go to a discussion on APGW.



    I think my opinion is fairly clear, and that is, regardless of wether you believe in it (APGW) or simply believe it is a natural change that we have to ride out, conserving our EVERY resource is important. Waste not, want not is my M.O. I do agree that man has done some long term damage to this planet, but I suspect Mother Nature has some things up her sleeve that we have yet to see. She is a resilient woman who has been around for billions of years, and will continue to be here for billions more. Regardless of what man does on her surface.



    The reference to Carbon Foot print is to show the environmentalist who are dead set against the use of SIM systems that it has potential, even in THEIR arena, using THIER chosen verbiage.



    Sorry to cut the conversation short on this thread, and if you want to start one, I'd be glad (as I am sure millions of others would as well) to chime in.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Steamhead
    Steamhead Member Posts: 16,840
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    Sounds like it could work

    but we'd still need anti-freeze in the slab loops, correct?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Correct...

    Yes Frank, antifreeze is still required. No way around that.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Steamhead
    Steamhead Member Posts: 16,840
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    So

    we need a heat exchanger of some sort, assuming we don't want to fill the whole system with glycol..... were you going to go flat-plate or run the slab circuit thru the coil of an indirect, or something else?
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    All the above...

    I don't like the use of antifreeze unless absolutely necessary. I envision reverse indirects for stage 1, and WSHP tied to the potable side of the tanks for stage 2, and or the secondary side of heat exchangers going to other loads. As with any hydronic question, there is only one correct answer, and you already know what that answer is, so I won't say it again :-)



    Thanks for chiming in Frank. I always value your thoughts.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • RobG
    RobG Member Posts: 1,850
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    It Depends

    Nuf said :0)
  • hot_rod
    hot_rod Member Posts: 22,144
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    performance

    next put some numbers to the heat exchange. I suspect the slab would perform a lot like an un-insulated pool collector. Good efficiency when the operating temperature and ambient are close, but performance drops quickly as ambient temperatures drop.



    So the key would be storing this low temperature, maybe 100F? for thermal loads in the slab or boosting HP performance. Not a lot of use for thermal energy in the summer, as you know.



    The quest has always been, and continues to be storage. Water is fairly good, affordable, easily moved, but it takes a lot of insulated space. A portion will always escape, how much to spend keeping that to a minimum is the critical number.



    There are some prototype underground tanks being tested, one is 10- 12" of foam with a liner to handle the potential temperature of summertime solar from high temperature collectors. One in particular is designed for ground mount drainbacks and has a well for the pump installation.



    As you know there are several projects running where they are dumping summer thermal into the earth to store, data is being collected. It would be good to get some actual performance numbers from Drakes Landing and the Weller School in Fairbanks.



    The ability to capture and store, with the least amount of loss will be the key to this being a viable system, as I see it.



    Bristol would be a good contact for some data on nigh sky re-radiation. He has some systems up and running using this concept. And I'll bet a lot of data with the SolarLogic system he engineers.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Thanks HR...

    Appreciate your input.



    Matching load to availability or coming up with cost effective thermal storage will be key to the efficient operation, but all technically feasible in my opinion. I ran my idea by Robert Bean who gave me a bunch of leads to research work done by IGSHPA. We will have to develop the software necessary to model it, but that is the easy part:-)



    Thanks for contributing.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Rich_49
    Rich_49 Member Posts: 2,766
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    Tanks

    Mark , I think these guys are onto something . I have received pricing from them but won't post it here but will say they beat up all other products without negotiation . Have a look ,  http://cocoontanks.com/ . 

      James Schenk from Thermal Battery Systems in Montana has some real interesting stuff going on including data logging .
    You didn't get what you didn't pay for and it will never be what you thought it would .
    Langans Plumbing & Heating LLC
    732-751-1560
    Serving most of New Jersey, Eastern Pa .
    Consultation, Design & Installation anywhere
    Rich McGrath 732-581-3833
  • Gordy
    Gordy Member Posts: 9,546
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    In a Nut Shell

    You want to design a "system". Where its side benefit is snow melt essentially for free. Its main benefit is maintaining loads where as energy would be needed in the carbon arena anyway. I don't think your in the weeds at all, but as soon as snow melt comes in the conversation, description, The greenists will wonder why the energy is not diverted to something more useful. The Snow melt has to just happen with out forced interaction which I believe your trying to accomplish.





    The biggy is getting the snow melt to be "dependable" . because if someone wants snow melt its not going to be part time or a side benefit of a stored energy system. For the buyer who in the end wants a snow melt system the side benefit will be stored energy for other things.



    Sooo with that being said how is the system going to be marketed?



    Snow Melt

    Solar collection

    WSHP

    GSHP
  • Harvey Ramer
    Harvey Ramer Member Posts: 2,239
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    Interesting concept!

    I believe a snowmelt system, coupled with a ground loop heat exchanger would be the way to go. A WSHP to pull energy to and from. Properly designed, this would provide essentially free snow melt sourced from the groundloop with only a circulator to make it happen. Solar energy could be reaped during the day time and packed into the ground loop thereby raising the average Wintertime COP of the WSHP.



    During the summer cooling season, the snowmelt could serve as preliminary heat rejection station (night) before the water passes through the ground loop. The WSHP should have waste heat recovery built in, to supply both DHW and pool/spa heating. That would lower the net heat rejection to the SM and the Ground Loop heat exchangers.



    A HP water heater should be developed that could take advantage of the solar gains by the snowmelt system during the winter time.



    I think it could be very feasible and not as complicated as it appears on the surface.



    I'm not sure that bulk storage is a good idea. Probably would loose 75% of potential customers just at the thought of having a huge water tank in there basement or on there property. I would try to focus on using all components readily available that are expected and accepted by the public. Taking full advantage of all components that are already in place, reaps bigger benefits than a lot of people realize.



    Harvey
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Drawings...

    Here are some conceptual drawings I generated. My apologies for the roughness of some of them. I've been away from Visio for way too long.

    I am posting four concepts.:

    1. basic high efficiency SIM,

    2. High Efficiency SIM that also does DHW (for the family with lots of teens),

    3. SIM with single stage DHW preheat, and

    4., SIM with 2 stage DHW preheat.

    Comments and questions are welcome.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • hot_rod
    hot_rod Member Posts: 22,144
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    info on slab temperature

    http://www.lhaps.com/images/DogTemperatureArticle_09jun2010.pdf



    Probably not as warm where the tube would be located, but even 100- 120F would be a good amount of energy to add to 55F potable water to pre-heat DHW.,



    In reality the average household spends 300 bucks or so per year for DHW, so the DHW summer load is not what you want to chase. Wind and cold temperatures would make the outdoor slab a non-starter for thermal in all but the hot summer months.



    I found a really detailed German study on outdoor slabs for heat exchangers, lots of technical data, I'll look for the link again.



    I'd imagine Viessmann has researched your idea also. But after seeing that large ice storage device at ISH last year :) I don't think you can store the thermal energy efficiently and affordably to make the numbers work.



    Perhaps that is why Viessmann is looking at ice storage in the ground not high temperature water?



    Certainly the desire for Europe to move away from Russian oil drives the heat pump concept, but properly designed and applied it's tough to beat a heat pump. Spend all the extra cash on a PV array large enough to run the heat pump :) Here is the link to the ice storage device they had on display at ISH.



    http://www.youtube.com/watch?v=Z7qPCeRhbPc
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Thanks HR...

    Much appreciated as always.



    Obviously, this is still in its conceptual stages, and I don't want to limit the application to residential settings. Anywhere that there is a good and continuous hot water load is a good candidate. Restaurants are a great example. They can use the snowmelt system in the winter to avoid slip fall hazards, as well as decrease the maintenance costs (salt and chemicals are BAD for carpet and tile), and they can use the hot water it provides when available. Remember also that the operation of this system is not limited to the availability of solar energy falling upon the surface, although the advantages of that are quite obvious. There are times, at night, when the slab is still being exposed to significant energy potentials from the higher ambient air temperatures,



    In addition to DHW, there are a LOT of other thermal loads that can be satisfied with low temp (120 F) energy. Hot tubs, swimming pools, spas, even some space heating needs. As for storage, there are a whole bunch of new phase change materials coming across the pond that will revolutionize thermal energy storage. That, and good old Mother Earth (drakelanding.ca). Plus, as we have proven over the years, a slab, at night makes an excellent heat emitter, providing a passive cooling source for radiant cooling loads.



    I think it is a huge opportunity staring hydronic contractors in the face. Once we prove it is technically and economically viable, we (The RPA through IAPMO) can start pushing for tax credits for the equipment necessary (except for the slab and boilers) to make it work. How many square feet of snowmelt systems is currently sitting there doing nothing for most of the time, right next the the physical plant for heating hot water and buildings?



    I think just about every system I installed would make a great candidate. Plus, by cooling the slab, and keeping it relatively stable temperature wise, we lessen the opportunity for thermal expansion and stress related cracking of the slab. Imagine the looks on peoples faces when they step onto a pool deck that is cooled? Probably as nice as the look they have on their face when they step on a warm floor for the first time...



    Need to round up some volunteers (equipment manufacturers and end users as well) to document the potential to move the initiative forward. I have one candidate (consumer) already, and am looking for more.



    Did I mention that we can "make" water by keeping the slab below dew point, and can use that water to maintain our Xeriscape Landscaping? Green, green, green, green, green. Plus, by condensing moisture out of the atmosphere, we can slow down global warming, because in reality, its not the Co2 that's causing issues, it is WATER vapor :-)



    The Bean is giving me many articles from IGSHPA folks to read. They've been looking at this for some time now. I know of a building in Aspen Colorado that has received numerous awards for its design that uses its snowmelt system as a cooling tower.



    Thanks for chiming in Bob. I look forward to your contributions.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • hot_rod
    hot_rod Member Posts: 22,144
    edited July 2014
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    storing energy and delta Ts

    Lets assume you could get 130F from a black colored pad, and you had insulated storage in the ground to leverage that fairly consistent ground temperature.



    140F in a tank of hot water in the ground at maybe 60F, so an 80° ∆T grabbing at that stored energy.



    With a block of ice, say 20°F in 60° ground, only a 40° ∆T.



    With ice you could get ac with dehumidification, as you have a cold enough temperature to condense.



    In the Viessmann approach you transfer this energy with solar assisted heat pumps, no boiler comes close to the efficiencies the heat pump can. And the energy to run the HP could be with a PV array, that also could be also offsetting the buildings electrical loads.



    The PV array, maybe more of the system, qualifies for rebates, utility buybacks, or adding to the community solar garden.



    I just don't see solar thermal, even with the most efficient fossil fueled boiler back up coming close?



    I've been a die hard boiler and thermal guy all my life, but you cannot deny the HP and inverter technology when looking into the future.



    The Chiles boys did some pool deck recovery systems around here many moons ago. not sure if they are still operating, may have been solaroll systems?



    My next heat pump may be the size of my microwave, and an energy fence for my loop field



    http://www.energyfence.com
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    edited July 2014
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    But...

    What about degrading PV efficiencies over time?



    http://www.nrel.gov/docs/fy12osti/51664.pdf



    I hear what you are saying regarding a 300% efficient device versus a 95% device, but still, using a solar PV array at a 20% peak efficiency versus a flat plate at around 60%?



    My gut tells me we end up at the same place efficiency wise (except for your graphic delta T in storage example), but the ST systems efficiency will not degrade significantly over the life of the collectors, Having to completely replace the PV array before it has paid for itself just doesn't sit right with me for some reason. Plus, we can completely recycle a ST collector, but can't do the same with a PV array can we?



    Lots of numbers to chew on. :-)



    Buyer beware…



    Thanks again for chiming in.



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • hot_rod
    hot_rod Member Posts: 22,144
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    an unglazed collector, aka a radiant outdoor slab

    lying horizontal, what is the efficiency of that? Look at the performance slope on an unglazed collector, which a driveway or parking lot slab could be considered. Although an unglazed collector would have the absorber directly in the sun. The slab would have the absorber tubes 2-4" below the direct sun. So probably less efficient.



    An unglazed collector has great performance compared to flate plate or evac tubes when the ambient and fluid temperature are close. Once the ambient drops 10- 20 below the fluid the unglazed goes in the toilet, performance wise. Not to mention wind across the slab or vehicles parked over it in a commercial parking lot.



    So first consider the cost of tube and insulation, labor etc to install lets say 10,000 square feet of slab. How much would you bid to tube and insulate 10,000 sq ft of slab the was to be poured? Concrete and labor to install is already covered, just the cost to turn it radiant. Divide that by the efficiency of that slab collector across 12 months.



    I'm thinking that dollar amount spent towards flat plate or evac tubes would give you much more energy, and perform in the cold months to 120- 140F, whereas the slab would not exchange much energy below 80°F ambient.



    Here is a performance graph, notice how an unglazed collector drops as temperature drops. Once the ambient is about 20° cooler than the fluid, you performance is completely gone. unglazed collectors, or slabs are good for providing 80- 85 pool water temperatures in warm climates.



    That slab would make a great heat dump, but you have no solar thermal to dump :)



    Someone good with solar simulation could model 10,000 square feet of un-glazed collector with 10,000 gallon of storage and see what the SF is. Then model that same load with flat plate or tubes and compare the required square footage and see how the costs work out.



    True the PV is less efficient compared to thermal collectors, but there is ALWAYS work for the pv, unless you have a consistent all day DHW load all year you thermal numbers will never pencil.



    Some thoughts for that load year around water parks, huge daily DHW and indoor pool loads. Prisons, plenty of them around, most over crowded. Predictable daily DHW loads.



    NRT Rob has some pretty good, actual data comparing PV to thermal on one of the solar threads, but not unglazed thermal.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • icesailor
    icesailor Member Posts: 7,265
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    Ancient Ideas:

    Just in case you didn't know, the concept is quite old. Storing energy in the ground for later use. I've spent my life reading useless but interesting (to me) articles about little or nothing. I read this article once about agricultural practices in ancient Bolivia at high altitude that some archaeologists "discovered". It was probably In Scientific American. They used to run a lot of articles on ancient peoples. Bolivia was part of an ancient civilization that in the end was part of the Inca Empire. Probably before that, the indigenous peoples developed a system of storing heat in the ground to raise crops at high altitude. They excavated large areas and made them flat, lined the bottoms with impervious earth and then rocks. Finally soil. They were built on raised beds and if it rained, it would trap the water and it acted as a reservoir. If there wasn't rain, it still held water and the roots would find the moisture. During the day, the soil heated up and retained heat. The water and soil transferred the heat to the rocks below. At night, when they might have radiational cooling, (heat from the land, radiating back into space because of a lack of clouds)  the rocks, moisture and soil kept the crops warm through the night. This is at elevations at and above 10,000'. In some places, they could get 3 crops of specialized foods like Potatoes, beans and Quinoa. The practice was lost when the Spanish made them switch to Spanish crops but it was re-discovered in the 1970's or somewhere.

    Its all related. Using the Sun and the Earth in passive ways. It just takes a lot of space. Here is a link to what is being done similarly today.

    Those old South American dudes were cleaver. In Peru, at one time, the Inca's decided to move a river from one side of a valley to the other side, to irrigate crops on the other side of the valley and stop flooding of the crops. So they did. It is perfectly sloped for its entire distance and is still visible today.

    How did they make the fields "dead level" like a lake? Anyone that is familiar with a water level should understand. A "Water Level" is a Third World Transit. How did they do what they did without a transit? Water seeks its own level. Or as I once said to someone having a problem understanding the concept of level, "You ever see a lake where the water was higher at one end than at the other?"  Take a large gourd, pot or container filled with water, put a stick or board, with two equally sized/lengths of wood, sticking up vertically from the board, and float it in the water filled container. Sight across the two small sticks and you have a perfectly level sight line. A Third World transit, almost as accurate as a $5,000 Laser Level. And  as accurate as a 6' level, stuck in a pile of hill sand and a 6' wooden rule, sighted to prove to a contractor that the building was sited 12" higher than it should have been according to the plan.

    But before anyone gets the puffed up chest from discovery, someone else did it before.

    But the modern concept for snow melt and radiational heat/cooling is sound with a long and practical history, Those old dudes may not have understood the theories, but it was FM that it worked. FM from the mythical dudes in the sky.



    http://www.new-ag.info/en/focus/focusItem.php?a=1015
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    All great points HR...

    And just so it is clear, I am not advocating flat concrete panels in lieu of properly placed solar collectors. I guess what I am saying, is if you are going to install a snowmelt system, why not take advantage of whats there energy wise for not a lot of extra cost and effort. It just seems to make sense to me. And yes, availability and load have to be matched, or storage taken into consideration, which will add costs. I see your points and they are well taken. It won't be for everyone, but commercially speaking, I do believe there may be some opportunities there that can and should be utilized.



    In order to test all of this, its going to require some dependable instrumentation. Do you know of any flow sensors that are reasonable in cost and can be compensated for use with fluids other than straight water? I believe you were working with some Grundfos flow meters at one point in time.



    I have the necessary computer power for data logging to show us the potential, and it is flexible enough to handle pretty much anyones sensors. I can get 32 points of monitoring, and 8 points of output control for fairly cheap. Just need the ultrasonic flow sensors to make it work.



    Thanks for your perspective.



    By the way, I seem to remember a European plan (Swedes or Danes) who were planning on doing this very thing (road based snowmelt/energy harvesting system). Wonder what ever happened with that?



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
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    Interesting stuff Chris...

    We could learn a LOT from the ancients, if we'd just listen :-)



    Oh wait, you and I are considered ancients, are we not :-)



    Borderline Dead Men, standing in line waiting for the next threshold…



    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • hot_rod
    hot_rod Member Posts: 22,144
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    understood and agreed

    the concept of storing energy in the ground. Really a GEO system IS solar energy. Cave dwellers in Colorado lived in a hole in the rock facing south. I doubt they had much snowmelt square footage, however.



    My question is how a surface slab could store or exchange energy better than well or trenches into the constant 55°f earth temperature.



    The insulated slab will hover around ambient except for sunny summer months. The bore holes or deep trenches always have around 55°F to offer.



    The surface slab sounds more like a large air to water exchanger that you can park on :)



    Sure there is some DHW pre-heat potential, not nearly what a manufactured collector could produce, however.



    We all know and acknowledge that energy storage is the holy grail. The whole world is looking for the best most efficient option, especially Europeans where todays fossil fuel price is $8.56 per gallon.



    So far this year I have read about energy storage in compressed air, latent HX materials, flywheel inertia, all sorts of batteries, it's all being considered.



    Best I can tell a modern HP with the latest refrigerants and high efficient ECM motor technology, tied into a earth loop or pond loop is as good as it gets. If you want heat, cooling and DHW at the flip of a switch, as most do, not under the suns fickle terms.



    I think we all agree on the HP as the key, the discussion seems to be slab on grade, or reach deeper into the ground for the energy exchange.



    I'm onboard for trying ME's concept, I just wonder how a residential pilot project, ME spoke of, without a huge summer DHW or heat load will pencil out? Nobody will spend $50,000 or more to save $300.00 per year?



    Currently they are capping off NG wells with a glut and low prices. If you have the $$ to install snowmelt, pay the NG costs so the oil guys can make a decent living and the radiant contractors have work. Isn't it mostly the oil folks building those custom homes with large snowmelts in the mountains, currently? Or their financial guys.



    With the US becoming the largest oil producer, better melt snow before the world comes shopping for that NG, prices may go up.



    Certainly the bright folks at NREL would have some knowledge in these areas, I'd like to hear their thoughts. All this is calculate-able, the data exists at places like IGSHP and NREL and many other Energy Universities across the world.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • icesailor
    icesailor Member Posts: 7,265
    edited July 2014
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    Ancients:

    I'm more ancient than you.

    Next time you have a moment to spare from your profession of trying to explain to "Youngsters" that thingy about "That might work for you. I've never seen it work for anyone else, but it might work for you" concept, read Jared Diamond's "Guns, Germ, and Steel. The Fates of Human Societies".  All those ancient societies that lived before, all crashed for one reason or another. Mostly because they used up all their food and other resources. Then, read his "Collapse. How Societies Choose to Fail or Succeed". Easy and fun reads. Like "Knock me in the head" Reads. Like Easter Island in the South Pacific. With all those statues and no people. Actually, in the 1700's when they were discovered, there were a few hundred people living there. The survivors that were still alive. The original people came from Polynesia. The Island was covered with giant trees and palm trees, Which they cut down to build houses and roll the giant statues they erected to whomever, fuel to cook with. They introduced rats which ate all the palm nuts and the Palm Trees all died off. They cut down the trees to plant crops but soil erosion ruined the soil and lost it. They killed and ate the nesting shore birds and ate their eggs. So they wiped out nesting sea birds. And the rats ate the rest of the eggs. And they fished out the waters of edible shellfish and large edible fish species. When they got all done, and a population of close to 10,000, they had a big war and killed off a bunch of each other. Then, they starved to death and got the population down to sustainable levels. The same thing happened to Pitcairn Island where Fletcher Christian went to in Mutiny On The Bounty and the boys (and girls) went to hide from the British. The Polynesians had already been there, stripped the resources and died off. ALL of them.



    Of interest to you would be his discussion of his favorite State to your North, Montana. Where it is an environmental disaster. He doesn't discuss Colorado, but just look in the mirror. The Colorado river doesn't run to Mexico now, it ends on the US side in California. Did the USA stealing Texas, New Mexico, Arizona, and California from Mexico give us all the water rights to water flowing into Mexico? Will they have to stop watering all those desert golf courses in Phoenix and give some water back to Mexican farmers? When you look at the Colorado River, or follow the US Interstate where the Welfare Cowboys had their standoff with the BLM folks trying to get illegal cattle of OUR land, and you look down from space on Google earth, notice all those big round green circles along the road. Are those agricultural crops being watered by big impact sprinkler water cannons in the middle of a field of fertilized green surrounded by yellow desert and sagebrush? Is that ground water laced with the residue of acid/cyanide heap recovery gold mining? Like what is polluting Montana?

    No water, no crops, no food, no people. And the water going in to hydronic heat/cool systems better be treated first.



    If you are at all interested in the Natural History and geology/archeology of your new Western home, "Collapse" is an interesting. It isn't a book about Climate change. All the glaciers are melting in Montana's Glacier National Park, so they don't provide melt water for rivers and streams. But he points out what a great idea it is for countries to send their raw materials (cheap) to other foreign countries, where labor is cheap and environmental laws are non-existant, and then buy back the finished goods to be sold back for cheap in the country that provided the raw materials.

    Read that while doing what I used to do when working on 8,000 Sq. Ft summer cottages by the beach. Where the owners spend Spring & Fall in the Hamptons and Winters in South Florida. In gated communities.

    Have you developed a jaded point of view like I have in my old age yet?

    It might happen.

    Please excuse and understand my snarky-ness. It come from becoming a grumpy old man with no service calls to attend to.
  • icesailor
    icesailor Member Posts: 7,265
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    Oil V Gas:

    (( Currently they are capping off NG wells with a glut and low prices. If you have the $$ to install snowmelt, pay the NG costs so the oil guys can make a decent living and the radiant contractors have work. Isn't it mostly the oil folks building those custom homes with large snowmelts in the mountains, currently? Or their financial guys.



    With the US becoming the largest oil producer, better melt snow before the world comes shopping for that NG, prices may go up. ))



    Drillers capping of fracked gas wells? Us is largest world producer of oil now?

    The Wall Street Crime Syndicate has this all in their 20 year plan to own the world.

    You think all that "new" oil will be sold for US consumption? It will be refined here or shipped unrefined to another country and sold on the world market. Once they have eliminated oil as a heating/DHW source in the USA, All the Frack Gas caps will come off and the prices for Nat Gas will be heading up to European prices. And the same with fuel oil. At $8.00+ per gallon, you will hear the Banksters on Wall Street crying poverty. They're barely covering expenses.



    That Fracked gas? Will all be compressed into LNG and shipped to the worlds markets to compete with Siberian (Russian Gas) to save Europe &China from the Great Russian Bear. The only part of some of that Fracked Gas some will see is in the polluted tap water coming out of your kitchen faucet that you can heat instant coffee with. If you light a match and set it on fire. We used to import LNG from Algeria and Libya to the USA. We've stopped that. We'll be shipping that LNG to Europe to get back at the Russians for futzing with the Wall Street Crime Syndicate.
  • jumper
    jumper Member Posts: 2,255
    Options
    no solar collector

    Maybe you don't need no stinking solar collector? Ever notice how snow disappears under a maple tree? So...... maybe you just have to insert pipes or rods thirty feet down to draw geothermal heat up to driveway. I never heard of it but I'm interested in how well that would work and also what objections envirowhackos will fabricate.