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How to model borehole ground heat storage/recovery in EnergyPlus

Hi, Currently I am using TRNSYS for plant loop modeling, but verifying E+ capabilities too. One of the types used there is Type257a for ground heat storage, a modification on Type 557 (ground heat exchanger) to be used with simultaneous charging and discharging using four pipe boreholes with two independent counter-current circuits, developed by S. Chapuis and M. Bernier on their work " SEASONAL STORAGE OF SOLAR ENERGY IN BOREHOLE HEAT EXCHANGERS". I know EnergyPlus has the GroundholeHeatExchanger:Vertical component, but I would know if is possible to model ground heat storage as well. Any input is appreciated. Thanks

Edit: added a diagram image description

saccon's avatar
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saccon
asked 2017-04-13 13:17:39 -0600
__AmirRoth__'s avatar
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__AmirRoth__
updated 2017-05-05 10:16:06 -0600
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Welcome to Unmet Hours! To clarify, do you want to model a buried / underground thermal storage tank, or account for the thermal storage effects of the ground volume surrounding the ground heat exchanger?

Aaron Boranian's avatar Aaron Boranian (2017-04-13 13:35:57 -0600) edit
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Hi Aaron. Thanks for the welcome and the comment. It is a tankless system. We only account the ground volume around the heat exchanger.

saccon's avatar saccon (2017-04-13 14:02:18 -0600) edit
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The GroundHeatExchanger:Vertical object in EnergyPlus has an input field where you define the ground conductivity, heat capacity, and far-field temperature. EnergyPlus uses these inputs to determine interactions between the ground heat exchanger and the working fluid. There are EnergyPlus objects for other ground heat exchanger models (slinky, pond, surface, and horizontal trench), which have similar input fields to define the ground.

You could also read the Engineering Reference documentation for EnergyPlus that describes G-factors and other parameters that are involved in the heat exchanger calculations.

Aaron Boranian's avatar
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Aaron Boranian
answered 2017-04-13 15:59:43 -0600
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Dear Aaron, I am having some unexpected results when changing the ground thermal conductivity, the length of the boreholes and the diameter, the changed value does make any difference in the heat pump consumption nor in the building response. I am wondering if EPlus is a software for such an analysis or am I doing some thing wrong in my model. Thanks in advance for any help in this regards.

Qamar's avatar Qamar (2023-04-21 11:04:02 -0600) edit
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@Qamar is this related to a post that you created? If so, you can upload your IDF to Google Drive, Dropbox, etc. and then share a link there for others to review your model inputs.

Aaron Boranian's avatar Aaron Boranian (2023-04-21 12:12:04 -0600) edit
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Yes thank you. I will post my model there.

Qamar's avatar Qamar (2023-04-22 11:53:25 -0600) edit
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