Optimized Thermodynamics and Building Physics of large-scale Thermal Energy Storage
Abstract
Seasonal thermal energy storage (TES) systems are a key element to promote the increase of renewable energy in district heating networks. Their complex dynamic operation within the energy system as well as their interaction with the surrounding environment requires detailed planning and design. The TES envelope plays a key role: the TES efficiency and the temperature of the surrounding ground are strongly influenced by the thermal losses through the cover and walls. Numerical simulations are a fundamental step to define the baseline targets for the optimal TES performance. Materials testing are required to assess the effective performance of the selected materials under the specific TES operating conditions and to support the design of the specific envelope performance. The construction of mock-ups is a third element to verify the test results and to identify possible challenges in the real scale application. In this work, these three elements are mutually integrated to support the design and optimization of the final TES structure with particular attention in preventing the formation of convective heat flux within the insulation layer.