Possibility for the leakages of the heat transfer medium in the underground TES systemsĬynthia Ann Cruickshank, Christopher Baldwin, in Storing Energy (Second Edition), 2022 8.2.2 Borehole thermal energy storageīorehole thermal energy storage (BTES) is one of the most common methods used for seasonal thermal energy storage currently employed around the world. Įnvironmental impacts due to the changes in the hydrological, biological, and geotechnical aspects of the underground.Įconomic risk factors between the utility and the facility operations in terms of electricity pricing policy.ĭisposal of the chemically derived PCMs and thermochemically reactive constituent materials into the environment without proper treatment as per the Standards and Regulations.Space requirements for the installation of the system Inherent thermal losses from the storage system by means of conduction and residual stored energy loss Stratification problems in realizing STES systems implementation Issues related to the storage and release of thermal energy at a constant temperature On the other hand, there are some major limitations in the successful installation and the operational aspects of the TES systems from the societal point of view, which include This chapter on BTES will define BTES in the wide context as given by IEA ECES (1997) and Nordell (2000), but will focus on larger applications with multiple boreholes and active storage, with or without the assistance of heat pumps. A distinction suggested by Sanner and Stiles (1997) is that if less than 25% of the annual thermal turnover from the borehole system is being exchanged with the surroundings, the BHE system would qualify as a BTES system. The distinction between vertical GSHP systems and BTES is vague. 11), BTES is said to consist of several closely spaced boreholes, but also that many countries have thousands of BTES systems with one to a few 100 boreholes, usually for heating and cooling of buildings. He defined BTES as multiple-borehole systems in rock, soil, or clay. 98) makes a distinction between BTES and “true BTES,” which in the latter case implies systems where the cold is actively stored and not passively recharged by heat transfer from the surroundings. 395–396) defined BTES as “deliberate thermal energy storage” in multiple-borehole systems with closed loops. In Paksoy (2007), BTES is defined differently by the various chapter authors, but the given examples are all multiple-borehole systems for seasonal storage of heat and cold. His definition of BTES comprised systems that provide cooling and/or heating, with or without heat pumps and with or without recharge, at all temperature levels, and any number of boreholes or ducts in rock, soil, or clay. He divided the technology into small-scale, large-scale, and seasonal storage. Nordell (2000) gave a wide but detailed definition of BTES. The energy recovered or stored in the subsurface environment is used for heating and cooling.

33) defined BTES as systems where rock or soil is the energy storage medium accessed by closed-loop heat exchangers placed in boreholes. There are diverse definitions of BTES in the literature. Gehlin (2015).īTES systems are referred to by many names in the literature including “ground heat store,” “borehole store,” “borehole heat store,” “seasonal thermal energy storage in rock ducts or ground,” “energy storage with borehole heat exchangers (BHEs),” “ground-coupled thermal energy storage (GCTES),” “storage system in rock,” “multiple-well storage system,” “vertical heat exchanger store,” and “vertical loops.” BTES systems do not necessarily use heat pumps, but when they do, they are sometimes referred to as “geothermal heat pump systems,” “ground-coupled heat pump (GCHP) systems,” “ground-source heat pump (GSHP) systems,” or “geo-exchange systems.”

Borehole thermal energy storage drilled in rock (left) and with pipes inserted in clay (right). Each lesson is linked closely with the AQA scheme of work. Some activities are differentiated for different abilities. Resource includes lesson plans, complete powerpoints, starter activities, lots of main activities, assessment for learning, homework and worksheets. The whole unit should take 6 hours to teach. Complete scheme of work for chapter 4.1.2 of AQA Chemistry (Trilogy) covering:

Chapter 6 periodic table chemistry tes