, as the UPHES-PTES hybrid storage, could also grant a low LCOS, a low investment (compounded Capex of only 4 USD/kWh thermal, for a 216 h storage) and low-emissions for the faster deployment of solar and wind, deemed to displace fossil fuels in future district heating and cooling networks, as required by cities and by most industrial developments

, Pending Patent: Dispositif hybride de stockage ou de conversion énergétiques, à fluide propulseur liquide, gazeux ou supercritique, filed at INPI, by Pascal Lalanne holder of patent rights, 2019.

M. Ram, D. Bogdanov, A. Aghahosseini, A. Gulagi, A. S. Oyewo et al., Global Energy System based on 100% Renewable Energy-Energy Transition in Europe Across Power, Heat, Transport and Desalination Sectors; Study by LUT University and Energy Watch Group, International Energy Agency. The Future of Cooling, 2018.

G. Cavazzini, Solutions for Pumped Hydro Energy Storage Plants, Sci, 2018.

A. Tallini, A. Vallati, and L. Cedola, Applications of micro-CAES systems: Energy and economic Analysis, Energy Procedia, vol.82, pp.797-804, 2015.

M. Mercangöz, J. Hemrle, L. Kaufmann, A. Z'graggen, and C. Ohler, Electrothermal energy storage with transcritical CO2 cycles, vol.45, pp.407-415, 2012.

J. D. Mctigue, A. J. White, and C. N. Markides, Parametric studies and optimisation of pumped thermal electricity storage, Appl. Energy, vol.137, pp.800-811, 2015.

S. Georgiou, N. Shah, and C. N. Markides, A thermo-economic analysis and comparison of pumped-thermal and liquid-air electricity storage systems, Appl. Energy, vol.226, pp.1119-1133, 2018.

A. Dietrich, F. Dammel, and P. Stephan, Exergoeconomic Analysis of a Pumped Heat Electricity Storage System with Concrete Thermal Energy Storage, Int. J. Thermodyn, vol.19, p.30, 2016.

E. Pujades, T. Willems, S. Bodeux, P. Orban, and A. Dassargues, Underground pumped storage hydroelectricity using abandoned works (deep mines or open pits) and the impact on groundwater flow, Hydrogeol. Geol, vol.24, pp.1531-1546, 2016.

B. Shell-internationale-research-maatschappij and . Of-netherlands, Storage and Recovery. Patent No. 0196 690, 1989.

J. Bi, T. Jiang, W. Chen, and X. Ma, Research on Storage Capacity of Compressed Air Pumped Hydro Energy Storage Equipment, vol.5, pp.26-30, 2013.

A. Odukomaiya, A. Abu-heiba, K. R. Gluesenkamp, O. Abdelaziz, R. K. Jackson et al., Thermal analysis of near-isothermal compressed gas energy storage system, Appl. Energy, vol.179, pp.948-960, 2016.

J. Johansson, Storage of highly compressed gases in underground Lined Rock Caverns-More than 10 years of experience, Proceedings of the World Tunnel Congress 2014-Tunnels for a Better Life, pp.9-15, 2014.

J. Rutqvist, H. M. Kim, D. W. Ryu, J. H. Synn, and W. K. Song, Modeling of coupled thermodynamic and geomechanical performance of underground compressed air energy storage in lined rock caverns, Int. J. Rock Mech. Min. Sci, vol.52, pp.71-81, 2012.

H. M. Kim, J. Rutqvist, J. H. Jeong, B. H. Choi, D. W. Ryu et al., Characterizing Excavation Damaged Zone and Stability of Pressurized Lined Rock Caverns for Underground Compressed Air Energy Storage, 2014.

H. M. Kim, D. Park, D. W. Ryu, and W. K. Song, Parametric sensitivity analysis of ground uplift above pressurized underground rock caverns, Eng. Geol, vol.135, pp.60-65, 2012.

P. Perazzelli and G. Anagnostou, Design issues for compressed air energy storage in sealed underground cavities, J. Rock Mech. Geotech. Eng, vol.8, pp.314-328, 2016.

J. Tunsakul, P. Jongpradist, H. M. Kim, and P. Nanakorn, Evaluation of rock fracture patterns based on the element-free Galerkin method for stability assessment of a highly pressurized gas storage cavern, Acta Geotech, vol.13, pp.817-832, 2018.

R. Glamheden and P. Curtis, Excavation of a cavern for high-pressure storage of natural gas, Tunn. Undergr. Space Technol, vol.21, pp.56-67, 2006.

H. S. Laine, J. Salpakari, E. E. Looney, H. Savin, I. M. Peters et al., Meeting global cooling demand withphotovoltaics during the 21st century, R. Soc. Chem, 2019.

M. S. Shwartz and . University, Stanford Scientists Calculate the Carbon Footprint of Grid-Scale Battery Technologies, p.30, 2019.

D. E. Energinet and . Agency, Technology Data for Energy storage, p.30, 2018.

Y. M. Kim, D. G. Shin, S. Y. Lee, and D. Favrat, Isothermal transcritical CO2 cycles with TES (thermal energy storage) for electricity storage, vol.49, pp.484-501, 2013.

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