Hydrogen-based Energy Storage System Research Articles

Off-Grid Multi-Carrier Microgrid Design Optimisation: The Case of Rakiura–Stewart Island, Aotearoa–New Zealand

The establishment of the concept of sustainable, decentralised, multi-carrier energy systems, together with the declining costs of renewable energy technologies, has proposed changes in off-grid electrification interventions towards the development of integrated energy systems. Notwithstanding the potential benefits, the optimal capacity planning of such systems with multiple energy carriers—electricity, heating, cooling, hydrogen, biogas—is exceedingly complex due to the concurrent goals and interrelated constraints that must be relaxed. To this end, this paper puts forward an innovative new optimal capacity planning method for a first-of-its-kind stand-alone multiple energy carrier microgrid (MECM) serving the electricity, hot water, and transportation fuel demands of remote communities. The proposed off-grid MECM system is equipped with solar photovoltaic panels, wind turbines, a hydrogen-based energy storage system—including an electrolyser, a hydrogen reservoir, and a fuel cell—a hybrid super-capacitor/battery energy storage system, a hot water storage tank, a heat exchanger, an inline electric heater, a hydrogen refuelling station, and some power converters. The main objective of calculating the optimal size of the conceptualised isolated MECM’s components through minimising the associated lifetime costs is fulfilled by a specifically developed meta-heuristic-based solution algorithm subject to a set of operational and planning constraints. To evaluate the utility and effectiveness of the proposed method, as well as the technical feasibility and economic viability of the suggested grid-independent MECM layout, a numerical case study was carried out for Rakiura–Stewart Island, Aotearoa–New Zealand. Notably, the numeric simulation results highlight that the optimal solution presents a low-risk, high-yield investment opportunity, which is able to save the diesel-dependent community a significant 54% in electricity costs (including electrified space heating)—if financed as a community renewable energy project—apart from providing a cost-effective and resilient platform to serve the hot water and transportation fuel needs.

Design and feasibility analysis of hydrogen based hybrid energy system: A case study

Renewable energy sources can produce less carbon than conventional energy sources, which has the significant disadvantage of being intermittent, which triggers a stable storage system. This work focuses on the issues of hydrogen energy storage which can solve the fluctuating output power problem by simulating results on HOMER software. Three combinations of the Solar-Hydrogen system, Wind-Hydrogen system, and Solar-Wind-Hydrogen hybrid system are presented to find the most optimum one. Levelized Cost of Energy (LCOE) for Hybrid System has proven to be the most economical while the Wind Turbine cost 1.476% higher and the Solar Photovoltaics (PV) System costs 108.03% more. LCOE for Hybrid Model is $0.3387, while for Solar System it is $ 0.7046 and for Wind System it is $ 0.3437. These results show that a hydrogen-based energy storage system is viable for the considered.

Optimal operations for hydrogen-based energy storage systems in wind farms via model predictive control

Efficient energy production and consumption are fundamental points for reducing carbon emissions that influence climate change. Alternative resources, such as renewable energy sources (RESs), used in electricity grids, could reduce the environmental impact. Since RESs are inherently unreliable, during the last decades the scientific community addressed research efforts to their integration with the main grid by means of properly designed energy storage systems (ESSs). In order to highlight the best performance from these hybrid systems, proper design and operations are essential. The purpose of this paper is to present a so-called model predictive controller (MPC) for the optimal operations of grid-connected wind farms with hydrogen-based ESSs and local loads. Such MPC has been designed to take into account the operating and economical costs of the ESS, the local load demand and the participation to the electricity market, and further it enforces the fulfillment of the physical and the system's dynamics constraints. The dynamics of the hydrogen-based ESS have been modeled by means of the mixed-logic dynamic (MLD) framework in order to capture different behaviors according to the possible operating modes. The purpose is to provide a controller able to cope both with all the main physical and operating constraints of a hydrogen-based storage system, including the switching among different modes such as ON, OFF, STAND-BY and, at the same time, reduce the management costs and increase the equipment lifesaving. The case study for this paper is a plant under development in the north Norway. Numerical analysis on the related plant data shows the effectiveness of the proposed strategy, which manages the plant and commits the equipment so as to preserve the given constraints and save them from unnecessary commutation cycles.

Large-vscale hydrogen production and storage technologies: Current status and future directions

Over the past years, hydrogen has been identified as the most promising carrier of clean energy. In a world that aims to replace fossil fuels to mitigate greenhouse emissions and address other environmental concerns, hydrogen generation technologies have become a main player in the energy mix. Since hydrogen is the main working medium in fuel cells and hydrogen-based energy storage systems, integrating these systems with other renewable energy systems is becoming very feasible. For example, the coupling of wind or solar systems hydrogen fuel cells as secondary energy sources is proven to enhance grid stability and secure the reliable energy supply for all times. The current demand for clean energy is unprecedented, and it seems that hydrogen can meet such demand only when produced and stored in large quantities. This paper presents an overview of the main hydrogen production and storage technologies, along with their challenges. They are presented to help identify technologies that have sufficient potential for large-scale energy applications that rely on hydrogen. Producing hydrogen from water and fossil fuels and storing it in underground formations are the best large-scale production and storage technologies. However, the local conditions of a specific region play a key role in determining the most suited production and storage methods, and there might be a need to combine multiple strategies together to allow a significant large-scale production and storage of hydrogen.

Optimal Integration of Hydrogen-Based Energy Storage Systems in Photovoltaic Microgrids: A Techno-Economic Assessment

The feasibility and cost-effectiveness of hydrogen-based microgrids in facilities, such as public buildings and small- and medium-sized enterprises, provided by photovoltaic (PV) plants and characterized by low electric demand during weekends, were investigated in this paper. Starting from the experience of the microgrid being built at the Renewable Energy Facility of Sardegna Ricerche (Italy), which, among various energy production and storage systems, includes a hydrogen storage system, a modeling of the hydrogen-based microgrid was developed. The model was used to analyze the expected performance of the microgrid considering different load profiles and equipment sizes. Finally, the microgrid cost-effectiveness was evaluated using a preliminary economic analysis. The results demonstrate that an effective design can be achieved with a PV system sized for an annual energy production 20% higher than the annual energy requested by the user and a hydrogen generator size 60% of the PV nominal power size. This configuration leads to a self-sufficiency rate of about 80% and, without public grants, a levelized cost of energy comparable with the cost of electricity in Italy can be achieved with a reduction of at least 25–40% of the current initial costs charged for the whole plant, depending on the load profile shape.

How can the integration of renewable energy and power-to-gas benefit industrial facilities? From techno-economic, policy, and environmental assessment

This paper applies a mixed integer linear programming model developed in GAMS to simulate the integration of Power-to-Gas infrastructure into an industrial manufacturer's energy system subject to the existing thermal and electrical energy demands, as well as a third hydrogen energy profile. This work is novel in that it assesses the challenges and economic incentives available to make feasible the installation of a hydrogen-based energy storage systems within the Province of Ontario from a techno-economic, policy and environmental perspectives.The energy hub analyzed in this work uses electricity from the power grid and solar PVs to meet the manufacturer's demands, while converting the excess to hydrogen gas, which is used across an array of pathways to generate revenue. ThisThis includes a blend ofof hydrogen for fuel cell vehicles (FCVs), hydrogen for forklifts, and the direct injection of hydrogen into the facility's natural gas, adding renewable content to the heating, and manufacturing processes. Our primary objective was to implement a safe design that minimizes capital and operating costs, resulting in a favorable business case for producing hydrogen, and providing ancillary grid services. However, Power-to-Gas creates a net-emission reduction that can be used not only to sell emission allowances in the provincial carboncarbon tax program for up to $30/t-CO2eq but to assist the Company in achieving their strategic emission reduction targets.Installation of the selected Power-to-Gas system would require a total capital investment of $2,620,448 with the electrolyzers and solar panels accounting for 41% and 17% of the capital costs, respectively. The compressors will account for most of the operating costs which total $237,653 annually. Within the energy hub, 76,073 kg-H2 has been produced per year for end-use applications. A sensitivity analysis was performed by varying both hydrogen and carbon credit price which predicted a potentialpotential CO2 offset of 2359.7 tonne/yr with a payback period of as little as 2.8 years.

국내 전력 부하패턴 불균형 완화를 위한 수소 기반 에너지 저장 시스템 용량 산정 연구

국내 전력 부하패턴 불균형 완화를 위한 수소 기반 에너지 저장 시스템 용량 산정 연구

Numerical and Experimental Study on Operation of Reversible Solid Oxide Fuel Cells

Reversible solid oxide cells are considered to be a promising technology for hydrogen-based energy storage systems since the same device can be used to generate electricity, heat and valuable fuels in a highly-efficient manner. The knowledge of the processes and loss mechanisms involved at the electrochemical energy conversion is of special interest for the optimization of such systems as well as for the development of appropriate diagnostic tools. This study focuses on numerical and experimental investigation of losses that occur during the operation of solid oxide cells of commercial size in fuel cell and electrolysis mode with hydrogen and steam, based on which appropriate optimization of their operation can be suggested.

Thermodynamic and economic analysis of a hybrid ocean thermal energy conversion/photovoltaic system with hydrogen-based energy storage system

The purpose of this study is to define and assess a new, renewable and sustainable energy supply system for islands and remote area where ocean thermal energy conversion (OTEC)/photovoltaic with hydrogen storage system is proposed. Components of this system are a turbine, generator, evaporator, condenser, pumps, photovoltaic panels, electrolyzer, hydrogen tanks, fuel cell and converter. To evaluate the proposed hybrid system, energy, exergy and economic analysis are employed. For OTEC, an optimization algorithm is applied to find the optimum working fluid (R134A, R407C, R410A, R717, R404A, and R423A), evaporation and condensation temperatures, and cold and warm seawater temperature differences between the inlet and outlet of evaporator/condenser. The results demonstrate that the maximum specific power of OTEC was achieved to be 0.3622 kW/m2 for R717 and 0.3294 kW/m2 for R423A working fluids. The overall energy efficiency for the hybrid renewable energy system was obtained 3.318%. The maximum energy loss was occurred by the turbine. The exergy efficiency of the hybrid system was obtained 18.35% and the payback period of the proposed system was obtained around 8 years. The unit electricity cost for the system was achieved as 0.168 $/kWh which is valuable compared to 0.28 $/kWh of the previous system.

Renewable hydrogen as an energy storage solution

The paper will discuss the potential of renewable hydrogen as an energy storage medium for the decarbonisation of multiple sectors and for the energy system security. The author will particularly focus on the applications related to the building industry with perspectives to be further developed. The paper will cover the most up-to-date initiatives addressing the combination of hydrogen production based on water electrolysis and solar energy methods with the possibility of hydrogen implementations for energy storage, transportation and stationary applications such as combined heat and power (CHP) plants or fuel cell electric generators. The opportunity to reach improved efficiency and cost-effectiveness in the energy transition will be presented on the example of the two selected case studies: the world’s first full-scale wind power and hydrogen plant and the most up-to-date on-going project chosen by Fuel Cells and Hydrogen Joint Undertaking. They will be analysed in purpose to draw the conclusions regarding the options and limitations of the actual renewable hydrogen based energy storage systems tested in the real life situation. The second aim of the paper is to formulate the recommendations for the further action in this field, including the reduction of some non-technological barriers.

Modelling and optimisation of a hydrogen-based energy storage system in an autonomous electrical network

The European Union’s 2020 climate and energy package (known as “20–20–20” targets) requests, among other key objectives, 40% of the electricity production in Greece to be supplied from Renewable Energy Sources by 2020. The main barriers for reaching this target is the intermittency of renewable energy sources combined with the penetration limits in the local electrical grids and the high seasonal demand fluctuations. In this context, the introduction of energy storage systems, comprises one of the main solutions for coping with this situation. One of the most promising technologies for storing the excess energy, that would be otherwise lost, is the production and storage of hydrogen through water electrolysis. Hydrogen can be used for supporting the electricity grid during periods of high demand but also as transportation fuel for hydrogen-based automobiles (e.g. fuel cell vehicles). For this purpose, a simulation algorithm has been developed, able to assess the specifications of the optimum sizing of hydrogen production storage systems. For the application of the algorithm, the area of the Aegean Sea has been selected, owed to the considerable renewable energy sources curtailments recorded in the various non-interconnected islands in the region. More specifically, the developed algorithm is applied to an autonomous electricity network of 9 islands, located at the SE area of the Aegean Sea and known as the “Kos-Kalymnos” electricity system. The results obtained designate the optimum size of the hydrogen-based configuration, aiming to maximize the recovery of otherwise curtailed renewable energy production.

Logan boosts clean energy at Levenmouth hydrogen project

Edinburgh-based Logan Energy has designed, supplied and installed a state-of-the-art hydrogen-based energy storage system and two mobile hydrogen vehicle refueling units at the Levenmouth Community Energy Project in Scotland, UK.

Primary and Albedo Solar Energy Sources for High Altitude Persistent Air Vehicle Operation

A new class of the all electric airship to globally transport both passengers and freight using a ‘feeder-cruiser’ concept, and powered by renewable electric energy, is considered. Specific focus is given to photo-electric harvesting as the primary energy source and the associated hydrogen-based energy storage systems. Furthermore, it is shown that the total PV output may be significantly increased by utilising cloud albedo effects. Appropriate power architectures and energy audits required for life support, and the propulsion and ancillary loads to support the continuous daily operation of the primary airship (cruiser) at stratospheric altitudes (circa 18 km), are also considered. The presented solution is substantially different from those of conventional aircraft due to the airship size and the inherent requirement to harvest and store sufficient energy during “daylight” operation, when subject to varying seasonal conditions and latitudes, to ensure its safe and continued operation during the corresponding varying “dark hours”. This is particularly apparent when the sizing of the proposed electrolyser is considered, as its size and mass increase nonlinearly with decreasing day-night duty. As such, a Unitized Regenerative Fuel Cell is proposed. For the first time the study also discusses the potential benefits of integrating the photo-voltaic cells into airship canopy structures utilising TENSAIRITY®-based elements in order to eliminate the requirements for separate inter-PV array wiring and the transport of low pressure hydrogen between fuel cells.

Research and development of a laboratory scale Totalized Hydrogen Energy Utilization System

Hydrogen is accepted as the energy carrier for future. Hydrogen based energy storage system represents an important option to store the fluctuating power generated from the renewable sources. A laboratory scale Totalized Hydrogen Energy Utilization System (THEUS) has been developed. THEUS consists of the Unitized Reversible Fuel Cell (URFC), which has both fuel cell and water electrolysis functions in one component, and hydrogen storage tank. THEUS was tested separately in water electrolyzer mode operation and fuel cell mode operation. THEUS was also tested continuously for three days to evaluate the energy efficiency. The URFC and hydrogen storage tank performance were characterized. In particular the overall system efficiency, stability upon cycling, and the reaction heat recovery rates of the metal hydride tank were discussed.

Safety strategy for the first deployment of a hydrogen-based green public building in France

HELION, a subsidiary of AREVA in charge of the business unit Hydrogen and energy storage, is deploying for the first time in a French public building, a hydrogen-based energy storage system, the Greenergy Box™. The 50 kWe system is coupled with a photovoltaic farm to ensure up to 45% electrical autonomy and power backup to the building. The safety system and siting measures of the complete hydrogen chain are described. The paper also highlights the work accomplished with Fire Authorities and Public to gain the acceptance of the project and allow the deployment of four other hydrogen-based green buildings.