Modeling Hydrogen Networks for Future Energy Systems: A Comparison of Linear and Nonlinear Approaches

Common energy system models that integrate hydrogen transport in pipelines typically simplify fluid flow models and reduce the network size in order to achieve solutions quickly. This contribution analyzes two different types of pipeline network topologies (namely, star and tree networks) and two different fluid flow models (linear and nonlinear) for a given hydrogen capacity scenario of electrical reconversion in Germany to analyze the impact of these simplifications. For each network topology, robust demand and supply scenarios are generated. The results show that a simplified topology, as well as the consideration of detailed fluid flow, could heavily influence the total pipeline investment costs. For the given capacity scenario, an overall cost reduction of the pipeline costs of 37% is observed for the star network with linear cost compared to the tree network with nonlinear fluid flow. The impact of these improvements regarding the total electricity reconversion costs has led to a cost reduction of 1.4%, which is fairly small. Therefore, the integration of nonlinearities into energy system optimization models is not recommended due to their high computational burden. However, the applied method for generating robust demand and supply scenarios improved the credibility and robustness of the network topology, while the simplified fluid flow consideration can lead to infeasibilities. Thus, we suggest the utilization of the nonlinear model for post-processing to prove the feasibility of the results and strengthen their credibility, while retaining the computational performance of linear modeling

Evaluación de la satisfacción y conocimientos en la rehabilitación del ictus tras la aplicación de medidas sistematicas de información, formación y soporte para pacientes y cuidadores

El ictus afecta abruptamente muchos aspectos de la vida del paciente superviviente y de sus familiares más cercanos. Su incidencia y el coste económico relacionado con la discapacidad secundaria van en aumento en la mayoría de países occidentales y en todo el mundo. El desarrollo de iniciativas que proporcionen de forma adecuada información sobre el ictus y su prevención, así como la formación necesaria para la adquisición de habilidades de auto-cuidado o manejo de estos pacientes, es clave para que una organización con recursos sanitarios limitados de respuesta a una sociedad que cada vez precisa con mayor nitidez una red socio-sanitaria integrada. La información precisa convierte a los pacientes y cuidadores en agentes activos con una mayor implicación en su proceso terapéutico, al mismo tiempo que reduce la incertidumbre y el miedo característicos después de un ictus. La formación del paciente y su cuidador en técnicas de auto-cuidado garantiza la máxima autonomía posible del paciente en su vida diaria, objetivo primordial del programa rehabilitador. A su vez, el soporte que desde las unidades de rehabilitación se proporcione al paciente con ictus y su familia es clave para reducir la soledad y aumentar los niveles de confianza y participación en la vida familiar o social de ambos. La satisfacción del paciente y cuidador con según qué aspectos del programa rehabilitador nos da información sobre si estamos respondiendo adecuadamente a sus necesidades más inmediatas después del ictus, y puede orientar al proveedor del servicio en cuanto a la organización del mismo. El aumento del nivel de conocimiento sobre el ictus del paciente y el cuidador, por otra parte, indica también que la medida educacional implantada está siendo eficaz. En este trabajo se evalúa la eficacia de una medida específica dirigida a proporcionar información, formación y soporte al paciente y su cuidador después del ictus. El aumento de la satisfacción de ambos, así como su nivel de conocimientos sobre esta afección demuestra que estas medidas son factibles y pueden ayudar en la adaptación de los pacientes y sus cuidadores en la nueva situación. Por otra parte, constatamos la necesidad de desarrollar en nuestro medio herramientas válidas que nos permitan evaluar los resultados de las intervenciones, ya sea en términos de satisfacción, conocimientos u otras variables de resultado. Por ello, se ha validado la versión en castellano de la Escala de Satisfacción de Pound, una herramienta específica, y con una gran aceptación internacional, para medir el grado de satisfacción del paciente con el programa rehabilitador seguido después del ictus. En base a nuestros resultados concluimos que la implantación sistemática de medidas dirigidas a la educación, formación y soporte de pacientes y cuidadores en el programa de rehabilitación seguido tras el ictus es factible y efectiva, y que la Escala de Satisfacción de Pound es una herramienta válida también en nuestro medio para medir la satisfacción con el programa rehabilitador seguido tras el ictus.Stroke abruptly affects many aspects of life of the surviving patients and their closest relatives. Incidence and the economic cost associated with secondary disability are increasing in most western countries and around the world. The development of initiatives that adequately provide information on stroke and its prevention, as well as the necessary training to acquire skills for self-care or management of these patients, is a key aspect for a care organization with limited health resources to respond to a society that increasingly needs, with greater clarity, an integrated socio-health network. Accurate information makes patients and caregivers in active agents with a greater involvement in their therapeutic process, while reduces uncertainty and fear, both characteristics after stroke. Patient education and caregiver training in self-care techniques ensures the maximum possible patient autonomy in their life, which is a primary objective in the rehabilitation program. Also support provided from stroke rehabilitation units for patients and their families is key to reduce their feelings of loneliness and increase levels of confidence and participation in family and social life. Patient and caregiver satisfaction with some aspect of the rehabilitation program gives us information about whether we are properly responding to their immediate needs after stroke, and can guide the service provider in terms of organization. The improvement in patients and caregivers' knowledge about stroke also may indicate that the educational measure is being implemented effectively. In this work we evaluate the efficacy of a specific measure to provide education, training and support for patients and caregivers after stroke. Increased levels of satisfaction, as well as the improvement of their knowledge about this condition shows this kind of measures are feasible and can help patients and caregivers adapt to the new situation. On the other hand, we note the need to develop valid tools that allow us to evaluate the results of new interventions, in terms of satisfaction, knowledge or other outcome variables. Therefore, we validate the spanish version of The Satisfaction Pound Scale, a specific tool and with a great international acceptance, to measure patient's satisfaction with the rehabilitation program after stroke. With this work we conclude that implementation of systematic measures for education, training and support for patients and caregivers in the rehabilitation program after stroke is feasible and effective, and that de Satisfaction Pound Scale is a valid tool also in our environment to evaluate patient satisfaction with the rehabilitation program after stroke

Power-to-hydrogen and hydrogen-to-X:Which markets? Which economic potential? Answers from the literature

Research carried out within the framework of Task 38 of the Hydrogen Implementing Agreement of the International Energy Agency. The task is coordinated by the Institute for techno-economics of energy systems (I-tésé) of the CEA, supported by the ADEME. The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.With the expansion of renewable energy’s contribution to the energy mix, balancing the electricity grid is becoming increasingly challenging. Alongside other solutions, Power-to-Hydrogen concepts are gaining significant interest. In this paper, the “Task 38”, initiated by the Hydrogen Implementing Agreement of the International EnergyAgency, presents the first of a two-step literature review regarding Power-to-Hydrogen and Hydrogen-to-X concepts with a focus on prospective market and economic potential. The study reveals a large scope of literature that shows a considerable variety ofsuggested implementation schemes. The transportation sector is identified as the most promising consumer market. Hydrogen-to-Gas pathways will require subsidies in order to be profitable. Hydrogen-to-Power becomes an economically promising option in the context of systems with high shares of renewables and a need for longer-term storages. Additionally, key enablers for Power-to-Hydrogen concepts are identified; namely support policies, concurrently with ongoing progress on the development and implementation of industry standard

Optimizing Cross-linked Infrastructure for Future Energy Systems

Increasing shares of distributed, intermittent renewable electricity generation as well as the need to decarbonize all sectors in future energy systems require new infrastructure solutions. In these infrastructure solutions, energy transmission and storage technologies will serve as spatial and temporal balancing options. Technologies like electrolyzers will be deployed to create a renewable link between the power sector and other sectors. Together with technologies for power generation from renewably produced gases, electricity and gas infrastructurewill be strongly cross-linked. The design of such cross-linked infrastructure is a computationally challenging undertaking and national cross-linked infrastructure analyses are scarce in literature...