POwer StoragE In D OceaN

Project Information

POSEIDON

Grant agreement ID: 101096457

DOI

10.3030/101096457

EC signature date 7 December 2022

Start date 1 January 2023

End date 31 December 2026

Funded under

• Climate, Energy and Mobility

Total cost

€ 4 993 106,98

EU contribution

€ 4 993 106,96

Coordinated by

ASOCIACION CENTRO TECNOLOGICO NAVAL Y DEL MAR
Spain

Periodic Reporting for period 2 - POSEIDON (POwer StoragE In D OceaN)

Reporting period: 2024-07-01 to 2025-12-31

Summary of the context and overall objectives of the project

POSEIDON aims to demonstrate that three innovative fast-response energy storage systems (ESS)—SMES, supercapacitors, and flywheels—can be safely and effectively integrated on board waterborne transport while remaining efficient and cost-competitive. To raise these technologies from low maturity to maritime relevance, the project will (1) build and marinize three ESS units with 20–200 kW power capacity, (2) validate them through 200 hours of operation in a maritime environment using a containerized system that includes all three, (3) refine a Levelized Cost of Storage (LCOS) metrics tool to assess and compare ESS across different waterborne segments, (4) deliver full life-cycle analyses of the three developed systems, (5) study potential integration with other disruptive technologies such as hydrogen, rigid sails, and reversible hydrokinetic generators, and (6) identify safety issues, long-term risks, and regulatory gaps while proposing pre-standardization and pre-regulation measures. Together, these activities contribute to the broader objective of clean, competitive, zero-emission waterborne transport.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During months M19–M36, POSEIDON progressed through manufacturing, validation testing, and preparation for integrating its three innovative energy storage systems (ESS). For the SMES (WP2), the consortium moved from prototypes to full-scale coils (PK01–PK04) using 2G HTS REBCO tapes, with precision winding, epoxy impregnation, and low-resistance indium-layer connectors. Full-scale tests in liquid helium (4.2 K) reached design currents but revealed radial buckling under combined thermal and electromagnetic loads, prompting a mechanical redesign with stainless-steel reinforcement, stronger fastening, and optimized coil spacing. For the flywheel KESS (WP3), a fully marinized system with a switched reluctance machine and reinforced mechanical assembly using hybrid ceramic ball bearings was built and successfully passed Factory Acceptance Tests (FAT), validating the bidirectional converter and mechanical behavior under simulated marine conditions, then delivered to CIEMAT for integrated lab testing. For the supercapacitor EESS (WP4), the full-scale system—two parallel strings of 15 modules plus a DC/DC power module and CompactRIO control—also passed FAT, confirming correct functionality, safety interlocks, and more than 3 MJ usable energy, and was delivered for lab integration. In modelling and integration (WP5), technical specifications were finalized for use cases with a short sea shipping ferry (Balearia) and an inland waterway vessel (Damen); detailed electrical, mechanical, and thermal models were integrated into a Dymola simulation, and the preliminary containerized demonstrator layout was completed and submitted for classification review. For safety (WP6), a goal-based regulatory gap analysis was carried out with ABS and three HAZID workshops identified key risks and required safeguards for onboard installation. For lifecycle and economics (WP7), the LCOS/LCC assessment framework was defined, prototype fabrication cost data collected, and initial LCC results produced, outlining investment, operation, and maintenance cost shares for each technology.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

During M19–M36, POSEIDON entered an advanced validation and integration-readiness phase for innovative maritime energy storage systems (ESS), delivering key technical results and clarifying what is needed for successful deployment. The project consolidated the SMES concept by confirming the suitability of second-generation high-temperature superconducting (2G HTS) REBCO tapes, valued for high power density and maritime applicability. In parallel, both the flywheel KESS and the supercapacitor EESS were manufactured and successfully passed Factory Acceptance Tests (FAT); the EESS proved it can deliver more than 3 MJ of usable energy for high-power transients. Multi-coil SMES testing revealed a radial buckling instability under combined thermal and electromagnetic loads, triggering a full mechanical redesign that adds stainless-steel reinforcement and optimizes inter-coil spacing to ensure structural integrity. On the safety and regulatory side, the consortium completed a Goal-Based Standards (GBS) regulatory gap analysis and ran three HAZID workshops with the American Bureau of Shipping (ABS), establishing the safety basis for each ESS technology. For integration, advanced electrical, mechanical, and thermal models were combined in a holistic Dymola simulation, and the preliminary layout of the containerized demonstrator was finalized.

These results support tangible impacts: for Inland Waterway Transport use cases, integrating these ESS can enable roughly 18–29% CO2 reduction, while targeting high efficiency (about 95–98% for SMES, 90–93% for KESS, and 85–95% for EESS). Technology maturity advanced from TRL 3/4 to 4/5, expanding electrification options for shipbuilders. To move from prototypes to market-ready solutions, POSEIDON highlights several needs: a full-scale 200-hour sea demonstration to generate real-world performance and safety evidence; continued work with classification societies (e.g. ABS and Bureau Veritas) to secure approvals and shape pre-standardization rules; stronger exploitation and market access support (including engagement with Horizon Europe BOOSTER); further refinement of the LCOS tool using fabrication and test data to benchmark profitability against batteries; IPR actions (patents/utility models) to protect outcomes; and continued research on HTS phenomena (screening currents, AC losses) that affect protection and quench mitigation.