Sizing and operation of energy storage by Power-to-Gas and Underwater Compressed Air systems applied to offshore wind power generation

Among the possible solutions for large-scale renewable energy storage, Power-to-Gas (P2G) and Compressed Air Energy Storage (CAES) appear very promising. In this work, P2G an innovative type of CAES based on underwater storage volumes (UW-CAES) are compared from a techno-economic point view, when applied in combination with 48 MWe offshore wind power plant, selecting appropriate location both high productivity favorable seabed depth. An optimization model is employed to study system design operation, maximizing lifetime plant profitability, while considering differential installation operation costs, market values products (i.e., hydrogen electricity), technological constraints. current economic scenario, resulting has nominal equivalent about 10% park capacity, small buffer. On other hand, compressor turbine UWCAES have close full farm large compressed air tanks required. Both options significantly impact management but most beneficial applications two systems different: results compact flexible unit, whereas UW-CAES able exploit higher average conversion efficiency (about 80% round-trip) against much installed investment cost. Anyway, framework, economics still inadequate, their competitiveness can improve compatible expected evolution markets next future.