Advances in Underground Thermal Energy Storage

Dear Colleagues,

We invite you to submit an original contribution to the Special Issue ‘Advances in Underground Thermal Energy Storage’. There is a global drive towards a net-zero carbon economy, which could be achieved with the help of underground thermal energy storage. Heating and cooling have to be decarbonised, since they account for much of the energy spent globally. For instance, within the EU, this accounts for half of the energy consumed. Presently, fossil-fuel-based heating is the main source of energy, and has to be replaced with alternative energy sources. The mismatch in demand and supply remains an issue to potential sources of renewable energy, such as solar and wind. Therefore, underground thermal energy storage could serve as the technology to enable the subsurface storage of heat to allow for a greater efficiency of renewable technologies. Heat can be stored underground (i) using borehole heat exchangers, (ii) in aquifers, (iii) in caverns or mines, (iv) in pits or (v) in tanks close to ground level. There are various sources of heat, such as renewables (e.g., solar–thermal collectors or curtailed wind) and waste-heat from industrial, domestic or nondomestic processes.

The aim of this Special Issue is to present advances in underground thermal energy storage. This can include case studies, theoretical studies, studies that involve system design, modelling, control, implementation, monitoring or optimisation, as well as reviews. Please also note that studies are not limited to subsurface technologies only, and the implementation of charge sources and demand (i.e., through heat networks) is also of interest.

Topics of interest include, but are not limited to:

• Borehole thermal energy storage;
• Aquifer thermal energy storage;
• Pit thermal energy storage;
• Mine thermal energy storage;
• Geothermal heating and cooling;
• Thermal response tests;
• Whole-system modelling;
• Heat networks;
• Surface analysis of demand and charge;
• Waste heat recovery;
• Energy efficiency;
• System optimisation;
• Economic analysis;
• Technological advances (including materials).

Dr. Isa Kolo
Dr. Christopher Brown
Dr. Chaofan Chen
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• borehole thermal energy storage
• aquifer thermal energy storage
• pit thermal energy storage
• mine thermal energy storage
• geothermal heating and cooling
• thermal response tests
• whole-system modelling
• heat networks
• surface analysis of demand and charge
• waste heat recovery
• energy efficiency
• system optimization
• economic analysis
• technological advances (including materials)