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Title: Thermal storage system with coupled tanks

Abstract

Methods and apparatus are disclosed for high-efficiency thermal storage with a fluid-filled “battery” tank positioned within a fluid-filled “reservoir” tank. Fluid loops couple the tanks to a heat pump and a building. The heat pump can charge the battery tank or deliver thermal energy (cold or heat) to a building, using the reservoir tank or ambient air as a thermal energy source. The battery tank can discharge energy to the building jointly with the heat pump or, at periods of peak electricity usage, with the heat pump switched off. Operating modes allow significant savings in electricity usage and mitigate the “duck curve.” Low duty cycle usage of the reservoir enables efficient underground thermal storage with less digging than conventional geothermal technologies. Additional efficiency is achieved with phase change materials installed inside a tank or in a tank wall, providing temperature regulation. Control methods are disclosed.

Inventors:
; ; ;
Issue Date:
Research Org.:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1925018
Patent Number(s):
11421914
Application Number:
17/434,264
Assignee:
UT-Battelle, LLC (Oak Ridge, TN); University of Tennessee Research Foundation (UTRF) (Knoxville, TN)
Patent Classifications (CPCs):
F - MECHANICAL ENGINEERING F24 - HEATING F24D - DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS
F - MECHANICAL ENGINEERING F24 - HEATING F24H - FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT GENERATING MEANS, IN GENERAL
DOE Contract Number:  
AC05-00OR22725
Resource Type:
Patent
Resource Relation:
Patent File Date: 03/13/2020
Country of Publication:
United States
Language:
English
Subject:
29 ENERGY PLANNING, POLICY, AND ECONOMY; 15 GEOTHERMAL ENERGY

Citation Formats

Liu, Xiaobing, Qu, Ming, Warner, Joseph K., and Shi, Liang. Thermal storage system with coupled tanks. United States: N. p., 2022. Web.
Liu, Xiaobing, Qu, Ming, Warner, Joseph K., & Shi, Liang. Thermal storage system with coupled tanks. United States.
Liu, Xiaobing, Qu, Ming, Warner, Joseph K., and Shi, Liang. Tue . "Thermal storage system with coupled tanks". United States. https://www.osti.gov/servlets/purl/1925018.
@article{osti_1925018,
title = {Thermal storage system with coupled tanks},
author = {Liu, Xiaobing and Qu, Ming and Warner, Joseph K. and Shi, Liang},
abstractNote = {Methods and apparatus are disclosed for high-efficiency thermal storage with a fluid-filled “battery” tank positioned within a fluid-filled “reservoir” tank. Fluid loops couple the tanks to a heat pump and a building. The heat pump can charge the battery tank or deliver thermal energy (cold or heat) to a building, using the reservoir tank or ambient air as a thermal energy source. The battery tank can discharge energy to the building jointly with the heat pump or, at periods of peak electricity usage, with the heat pump switched off. Operating modes allow significant savings in electricity usage and mitigate the “duck curve.” Low duty cycle usage of the reservoir enables efficient underground thermal storage with less digging than conventional geothermal technologies. Additional efficiency is achieved with phase change materials installed inside a tank or in a tank wall, providing temperature regulation. Control methods are disclosed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2022},
month = {8}
}

Works referenced in this record:

Including Energy Price in Optimizing Refrigerant System Operation
patent-application, January 2009


Heat pump and air conditioning system incorporating thermal storage
patent, October 1997


Self Sustaining Energy System for a Building
patent-application, May 2012