Understage energy storage tank

How do underground thermal energy storage systems work?

Underground thermal energy storage (UTES) systems store energy by pumping heat into an underground space. There are three typical underground locations in which thermal energy is stored: boreholes, aquifers, and caverns or pits. The storage medium typically used for this method of thermal energy storage is water.

What is underground thermal energy storage (Utes)?

Alessandro Casasso, ... Rajandrea Sethi The expression Underground Thermal Energy Storage (UTES) identifies shallow geothermal systems where heat from external sources (solar thermal collectors, industrial processes, combined heat and power systems) is stored seasonally into the ground to be used during periods of higher demand.

What are the limitations of underground thermal energy storage systems?

However, as reported by Lanahan and Tabares-Velasco (2017), limitations of underground thermal energy storage systems applied with elements such as energy piles include the comparatively large amount of heat loss compared to insulated water tank or gravel tank systems (Schmidt and Mangold, 2006; Rad and Fung, 2016).

How much does underground storage cost?

The costs of underground thermal energy storage (UTES) systems, such as boreholes and heat exchangers, range from 0.1 to 10 €/kWh. These costs depend heavily on local conditions. Compared to UTES, phase change material (PCM) storage and thermochemical storage (TCS) systems are significantly more complex and expensive.

Why is the underground a good place to store thermal energy?

The underground is suitable for thermal energy storage because it has high thermal inertia, i.e. if undisturbed below 10-15 m depth, the ground temperature is weakly affected by local above ground climate variations and maintains a stable temperature [76, 77, 78].

What is thermal energy storage (TES)?

Thermal energy storage (TES) is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes.