Air conditioner that stores cold in ice for later

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  • DanKegel
    Banned
    • Sep 2014
    • 2093

    #1

    Air conditioner that stores cold in ice for later

    No idea how cost-effective or energy-efficient this is, but for people with lots of solar panels who need lots of cooling after sundown, it's fun to think this unit might pay off:



    "Cooling Capability
    • Maximum Cooling Load .......................... 10 Tons
    • Total Storage Module Capacity .............. 20 Ton-hours Daytime Peak Power Reduction
    • On-Peak Power Reduction .................... up to 14 kW
    • On-Peak Electric Demand ..................... up to 300 Watts
    • Round Trip Efficiency: >95% using Ice Cooling, 100% DX
    • Energy Shifted Off-peak ........................ 28 kWh
    Nighttime Ice Make
    • Copeland Scroll Compressor ................... 4.3 T
    • Ice Make Time (full make) @ 55F ........... 6 hours
    • Ice Make Time (full make) @ 75F ........... 7.5 hours"

    14kW load is huge compared to a normal house's solar capability, so I am skeptical.
  • SunEagle
    Super Moderator
    • Oct 2012
    • 15151

    #2
    Originally posted by DanKegel
    No idea how cost-effective or energy-efficient this is, but for people with lots of solar panels who need lots of cooling after sundown, it's fun to think this unit might pay off:



    "Cooling Capability
    • Maximum Cooling Load .......................... 10 Tons
    • Total Storage Module Capacity .............. 20 Ton-hours Daytime Peak Power Reduction
    • On-Peak Power Reduction .................... up to 14 kW
    • On-Peak Electric Demand ..................... up to 300 Watts
    • Round Trip Efficiency: >95% using Ice Cooling, 100% DX
    • Energy Shifted Off-peak ........................ 28 kWh
    Nighttime Ice Make
    • Copeland Scroll Compressor ................... 4.3 T
    • Ice Make Time (full make) @ 55F ........... 6 hours
    • Ice Make Time (full make) @ 75F ........... 7.5 hours"

    14kW load is huge compared to a normal house's solar capability, so I am skeptical.
    While not efficient using solar to make ice (or cold energy storage) has been used by a number of people. If the initial cost can be reduced or if the cold storage energy could equal gird power costs you can justify the system.
    Last edited by SunEagle; 02-05-2016, 12:44 PM. Reason: spelling

    Comment

    • Logan005
      Solar Fanatic
      • Nov 2015
      • 490

      #3
      I had thought about a solar thermal trough design that uses coper pipes painted black containing ammonia feeding a condenser to remove the heat and then into an evaporator to adsorb the heat from indoors. similar to an RV propane refrigerator. It would be costly, but for an island/remote government building it could be viable.
      4X Suniva 250 watt, 8X t-105, OB Fx80, dc4812vrf

      Comment

      • sensij
        Solar Fanatic
        • Sep 2014
        • 5074

        #4
        This isn't being sold as a system to do what you are suggesting (store energy during the day to run an AC at night). It is being sold as a way to time shift the energy required to run the AC during the day... in other words, "charge up" the AC system at night when energy is cheap, then run the AC during the day for just the cost of the blower, not the compressor. The cost-effectiveness will depend on the differential between daytime and nighttime power and energy costs.

        For a solar application, if you need the AC at night, you probably need it even more during the day. You would need a seriously oversized PV system to not only run the AC during the day, but also bank enough energy in ice storage to continue running the AC at night at a lower cost that just running from the grid. Hard to see how that would ever make sense.
        Last edited by sensij; 02-05-2016, 03:55 PM.
        CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

        Comment

        • J.P.M.
          Solar Fanatic
          • Aug 2013
          • 14995

          #5
          Using The idea of thermal storage via latent heat of fusion, or melting/freezing, or more generally, large heat capacity, has been around for a long time - several thousand years if building integrated thermal mass is considered. There's not much new under the sun in that sense.

          It's pretty much analogous to the concept of storing electrical energy in batteries for later use, or time shifting for load management, cost savings or other reasons.

          Sizing/matching the thermal load and storage, and the particulars of the storage medium/heat exchange method/distribution system/etc. have been subjects of fairly recent ( ~ 40-50 or so years) efforts in alternate energy circles. For those interested, some of the most extensive efforts were headed by Doug Balcomb at Los Alamos. See the "Passive Solar Design Handbook", ISBN 0-89553-124-0, published 1983 for some details.

          To me, anyway and only, what the O:P has shown looks like another attempt to separate the energy ignorant from some of their financial assets. I'd turn up the summer setting on the thermostat before I'd spend the time/effort/money.

          Comment

          • jflorey2
            Solar Fanatic
            • Aug 2015
            • 2331

            #6
            Originally posted by DanKegel
            No idea how cost-effective or energy-efficient this is, but for people with lots of solar panels who need lots of cooling after sundown, it's fun to think this unit might pay off:
            Our company does this for one of our larger buildings. At night they run the chillers and cool down big tanks of eutetic salts. During the day they circulate water through the salt and use that for air conditioning.

            Comment

            • SunEagle
              Super Moderator
              • Oct 2012
              • 15151

              #7
              Originally posted by jflorey2
              Our company does this for one of our larger buildings. At night they run the chillers and cool down big tanks of eutetic salts. During the day they circulate water through the salt and use that for air conditioning.
              Cool. That is similar to where they use molten salt to store heat during the day and then use the heat to generate steam and electricity at night.

              Comment

              • J.P.M.
                Solar Fanatic
                • Aug 2013
                • 14995

                #8
                Originally posted by jflorey2
                Our company does this for one of our larger buildings. At night they run the chillers and cool down big tanks of eutetic salts. During the day they circulate water through the salt and use that for air conditioning.
                Dr. Telkes at U. of Delaware (SunEagle's Alma Mater I believe) probably did more on eutectic salts than most. Viable methods once corrosion and maint. are addressed. Times to cost effectiveness tended to be somewhat long, but have probably improved since last I checked several years ago. Economics of phase change materials were usually still not attractive vs. large water large chiller plants 10+ years ago.
                Last edited by J.P.M.; 02-08-2016, 11:14 PM.

                Comment

                • SunEagle
                  Super Moderator
                  • Oct 2012
                  • 15151

                  #9
                  Originally posted by J.P.M.

                  Dr. Telkes at U. of Delaware (SunEagle's Alma Mater I believe) probably did more on eutectic salts than most. Viable methods once corrosion and maint. are addressed. Times to cost effectiveness tended to be somewhat long, but have probably improved since last I checked several years ago. Economics or phase change materials were usually still not attractive vs. large water large chiller plants 10+ years ago.
                  Ah I remember those days back at U of D. When it was fun to be part of solar pv research.

                  Comment

                  • DanKegel
                    Banned
                    • Sep 2014
                    • 2093

                    #10
                    I saw a big array of ice storage systems at Los Angeles Community College recently. ( the vendor mentions them at http://www.calmac.com/energy-storage...energy-storage ) That's huge compared to the Ice Bear 20, though.

                    Comment

                    • J.P.M.
                      Solar Fanatic
                      • Aug 2013
                      • 14995

                      #11
                      Originally posted by SunEagle

                      Ah I remember those days back at U of D. When it was fun to be part of solar pv research.
                      Do you mean to imply you're not having fun now ?

                      Comment

                      • DanKegel
                        Banned
                        • Sep 2014
                        • 2093

                        #12
                        I love the 'satire in comic sans' convention!

                        Fun fact: one of my son's teachers required the students to use Comic Sans for an essay recently. No idea why.

                        Comment

                        • Sunking
                          Solar Fanatic
                          • Feb 2010
                          • 23301

                          #13
                          Originally posted by DanKegel
                          No idea how cost-effective or energy-efficient this is.
                          Well spoken Danny boy. I am proud of you as you finally admitted you have no clue.
                          Last edited by Sunking; 02-05-2016, 08:55 PM.
                          MSEE, PE

                          Comment

                          • DanKegel
                            Banned
                            • Sep 2014
                            • 2093

                            #14
                            Originally posted by J.P.M.
                            To me, anyway and only, what the O:P has shown looks like another attempt to separate the energy ignorant from some of their financial assets. I'd turn up the summer setting on the thermostat before I'd spend the time/effort/money.
                            Looks like both the Ice Bear and Calmac systems pay off for some people;
                            http://www.utilitydive.com/news/ice-...torage/408356/
                            discusses both, and mentions that some of the savings can come from reducing demand charges or getting paid by the utility for reducing load on demand.

                            Comment

                            • J.P.M.
                              Solar Fanatic
                              • Aug 2013
                              • 14995

                              #15
                              Originally posted by DanKegel

                              Looks like both the Ice Bear and Calmac systems pay off for some people;
                              http://www.utilitydive.com/news/ice-...torage/408356/
                              discusses both, and mentions that some of the savings can come from reducing demand charges or getting paid by the utility for reducing load on demand.
                              Looks to me they pay off mostly for the manufacturers if I read the text of that drivel correctly and believe any of it.

                              That link looks like little more than more time and energy wasted on hype and advertising masked as information and more of the same stuff you spread around here and probably elsewhere that does little or no good and often less. You keep spreading your tripe and I'll continue to call it tripe. Fair enough ?

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