LH2 Pioneer - Ultra-insulated seaborne containment system for global LH2 ship transport

Hydrogen is assumed to become low-to-zero-emission energy carrier of increasing importance. Hydrogen has several potential end-use applications in land and maritime transport, power and utilities, and as feedstock and energy input in several major industries. A major challenge to overcome is to enable cost- and energy-efficient production, storage and logistics solutions in order to efficiently connect supplies and demands locally, regionally, and globally. For long distances and large energy volumes, ship transport of liquid hydrogen is a promising alternative to become one of the major modes of transport, similar to the present-day LNG shipping and trade. Full-scale LH2 ship transport requires completely new containment systems for seaborne carriers, as well as systems for onshore storage and ship loading. A sufficient insulation standard must be developed and eventually proven to give satisfactory evaporation rates due to heat ingress. Therefore, the LH2 Pioneer project aims to develop a conceptual design for liquid hydrogen cargo tanks with 40-45,000 m3 volume and an energy capacity of roughly 100 GWh per tank. The insulation standard is targeted to give a daily evaporation loss down towards 0.1 %, that is, an inventory loss percentage equivalent to LNG cargo tanks of similar size. During the first year of the project, both a coarse-grained model and a more detailed model based on the finite element method (FEM) for calculating heat ingress in LH2 tanks have been built. The coarse model shows good accuracy relative to detailed finite element models and is computationally cheap and numerically robust. The total heat ingress into an LH2 tank operating at constant pressure may contribute either to evaporation of the liquid or to superheating of the gas inside the tank. Exactly how the heat is distributed depends on how the heat flows through and along the tank walls, as well as on how heat flows between the gas and liquid phases in the tank. In this project, studies of this distribution and the effect of evaporation losses have been initiated. Furthermore, work is underway to assess the possibilities of active cooling of the tank to reduce evaporation losses. In addition to the tank design and performance, the project develops conceptual solutions for adjacent key systems such as ship layout, ship propulsion powering, boiloff gas handling and LH2 loading and offloading. By taking a holistic system approach across these different disciplines, the project has analysed different ship configurations under varying operational scenarios such as ship speed, geographical route and weather conditions. The aim of the holistic analysis is to identify favourable technical and economical trade-offs between the interdependencies that arise between these part-systems. Examples of this is the need for balancing the boiloff rate with the ship’s own energy demands for propulsion and other onboard utilities in different phases of a voyage. Main results of the analysis are measured by key performance indices such as transportation efficiency and the levelized cost. The optimal boiloff rate and insulation level of LH2 tanks depends partly on how the boiloff gas is managed onboard. When there is an excess of boiloff gas beyond what is being used as ship fuel, it needs to be re-liquefied and returned to the storage tanks to maximize cargo delivery. Since hydrogen liquefaction is an energy- and capital-intensive process with otherwise complex configurations, the liquefaction systems for LH2 carriers have therefore been developed with rather simplified configurations compared to common onshore liquefaction systems. To enhance the onboard re-liquefaction efficiency, optimal use of the cold energy contained in the evaporated - but still cold - hydrogen gas has been analysed. The analyses show that the re-liquefaction of boiloff gas can still remain a significant energy and economic burden on the feasibility of LH2 ship transport. Therefore, various options for onboard boiloff gas management are being investigated to identify the optimal handling system from a techno-economic perspective. Examples of this are: Alternative refrigeration cycles, boiloff gas compression and storage in buffer tanks, and hybrid solutions of these options. Research partners in LH2 Pioneer are SINTEF Energi, SINTEF Ocean and NTNU. The project receives 17 million NOK from the Research Council and is additionally funded by industry partners Equinor, Gassco, Air Liquide, HD KSOE and Moss Maritime.

Hydrogen has the potential of becoming a major energy commodity and can enable low- or zero-emission energy use in several of the world's energy sectors, such as power generation, road and rail transport, sea transport and energy- and emission-intensive industries. A major challenge in a mass rollout scenario for hydrogen is energy- and cost-efficient storage, transport and distribution from origin to end users. For hydrogen value chains to become economically viable, large volumes and scaled-up technology is mandatory. Liquid hydrogen (LH2) transport and storage can play a major role in hydrogen trade. LH2 is a promising option and offers superior flexibility in the receiving end with respect to energy flux, purity, pressurisation and distribution. LH2P is organised to generate crucial new knowledge about the key technologies needed for feasible large-scale LH2 transportation, reflecting a high level of novelty and scientific ambition. The project aims to develop a pioneering conceptual design for a large and cost-efficient liquid hydrogen containment system with 40'-45 000 m3 volume per tank and boiloff rates feasible for deep sea transport, targeting 0.1 % per day, taking this to TRL 2-3 (analytical validation) and thus preparing for further increase to TRL 4-6 in subsequent development projects. LH2P will also work systematically to de-risk and advance the TRL of other associated technologies: Vessel hull design and propulsion and power system; Onboard boiloff gas handling system; LH2 loading systems for full-scale efficient and safe LH2 transfer onto carriers. LH2P fields a strong industry consortium and an ambitious dissemination plan, targeting the most important stakeholder groups. The scientific sphere will be targeted through peer-reviewed journals and conferences of high merit. Other target groups are governments, industry, trade associations, NGOs and the public sphere, all of which are targeted through appropriate channels in the dissemination plan.