Hydrogen-based Energy Storage System Research Articles

Techno-economic assessment of hydrogen-based energy storage systems in determining the optimal configuration of the nuclear-renewable hybrid energy system

Population growth and economic development have significantly increased global energy demand. Hence, it has raised concerns about the increase in the consumption of fossil fuels and climate change. The present work introduced a new approach to using carbon-free energy sources, such as nuclear and renewable, to meet energy demand. The idea of using the Nuclear-Renewable Hybrid Energy System (N-R HES) is suggested as a leading solution that couples a nuclear power plant with renewable energy and hydrogen-based storage systems. For this purpose, using a meta-heuristic method based on Newton's laws, the configuration of the N-R HES is optimized from an economic and reliability point of view. The optimal system is selected from among six cases with different subsystems such as wind turbine, photovoltaic panel, nuclear reactor, electrolysis, fuel cell, and hydrogen storage tank. Furthermore, the performance of hydrogen-based energy storage systems such as high-temperature electrolysis (HTE) and low-temperature electrolysis (LTE) is evaluated from technical and economic aspects. The results of this work showed that using nuclear energy to supply the base load increases the reliability of the system and reduces the loss of power supply probability to zero. More than 70 % of the power is produced by nuclear reactors, which includes more than 80 % of the system costs. The key findings showed that despite HTE's higher efficiency, using LTE as a storage system in N-R HES is more cost-effective. Finally, due to recent developments and the safer design of nuclear reactors, they can play an important role in combination with renewable energies to support carbon-free energy sectors, especially in remote areas, for decades to come.

Handling of long-term storage in multi-horizon stochastic programs

This paper introduces a method for incorporating long-term storage into the multi-horizon modelling paradigm, thereby expanding the scope of problems that this approach can address. The implementation presented here is based on the HyOpt optimization model, but the underlying concepts are designed to be adaptable to other models that utilize the multi-horizon approach. We demonstrate the effects of several formulations on a case study that explores the electrification of an offshore installation using wind turbines and a hydrogen-based energy storage system. The findings suggest that the formulations offer a realistic modelling of storage capacity, without compromising the advantages of the multi-horizon approach.

Physics of pressurized hydrogen spontaneous ignition in pipes containing bends of different angles

In the context of hydrogen-based energy storage systems, the safeguarding against spontaneous ignition during high-pressure hydrogen release is of paramount importance. This study delves into the thermal safety and management technologies pertinent to such systems by numerically investigating the effects of pipeline geometry on the risk of spontaneous ignition. Employing Large Eddy Simulation (LES) coupled with detailed chemical kinetics and a linear eddy model, the research assesses the impact of different pipe angles and burst pressures on ignition behavior. The simulations are validated against experimental data, ensuring the veracity of the findings. The results demonstrate a significant interplay between the ignition propensity and both the geometrical configuration of the pipeline and the pressure of hydrogen release. Notably, the emergence and interaction of transverse waves in pipe bends are revealed to amplify mixing processes, generating vortices that elevate the temperature and promote a conducive environment for chemical reactions leading to stable flame propagation. The ignition is shown to occur predominantly near the stoichiometric mixture ratio, suggesting a narrow ignition region. These insights are vital for enhancing the safety protocols and thermal management strategies of hydrogen-based energy storage systems, paving the way for safer and more efficient energy solutions.

Nanoscale Investigations of the Electric Double Layer in Protic Ionic Liquids

A hydrogen-based energy storage system will be the backbone of a future energy grid using renewable energies. Polymer electrolyte membrane fuel cells (PEMFCs) are a key element in this energy system as they convert chemical energy stored as hydrogen into electrical energy on demand. PEMFC systems, especially for automotive application, could be significantly improved by increasing the operation temperature above 100 °C. Protic ionic liquids are promising candidates as non-aqueous protic electrolytes for next-generation high-temperature polymer electrolyte membrane fuel cells. These fuel cells have a target operation temperature of 160 °C and allowing for a more efficient water and heat management compared to conventional Nafion®-based PEMFCs, which operate at temperatures below 80 °C [1].In order to ensure a reliable and efficient operation an electrolyte with a high electrochemical performance and stability has to be selected. For this purpose, protic ionic liquids have been proposed and first fuel cell tests have shown promising results [2]. Hence, we aim on understanding the properties of this class of novel electrolytes on an atomistic level, which would allow designing suitable material combinations and predicting their properties for an efficient fuel cell operation. As ionic liquids are molten salts, which are liquid below 100 °C, their electrochemical properties differ significantly from those of aqueous solutions. Instead of a classical electric double layer, which can be described by the models provided by Helmholtz, Gouy-Chapman and Stern, the interface structure formed between the electrolyte and a charged electrode is governed by the interplay between coulomb interaction and steric effects between the (large) molecular ions [3]. In order to understand the formation of this double layer on a metallic electrode, we employ atomic force microscopy and infrared spectroscopy in combination with molecular dynamics simulations. Our results show that in the interface region between the prototype protic ionic liquid diethylmethylammonium triflate ([Dema][TfO]) and a Pt electrode, a dense layered structure consisting of alternating anion and cation layers is present, that extends several nanometres into the bulk of the electrolyte [4]. The composition and structure changes with applied potential due to a preferential attraction of anions or cations depending on the electrode charge. When water is added to the ionic liquid, the layered structure becomes distorted and water molecules appear near the electrode. Since the presence of water will also influence the relevant electrochemical processes such as the oxygen reduction reaction (ORR), the analysis of the double layer structure on an atomistic scale is necessary in order to understand the subtle interactions between the molecules in the electrolyte and to propose design routes for novel more efficient ionic liquid-based electrolytes. Wippermann, K.; Suo, Y.; Korte, C. Oxygen Reduction Reaction Kinetics on Pt in Mixtures of Proton-Conducting Ionic Liquids and Water: The Influence of Cation Acidity. J. Phys. Chem. C 2021, 125, 4423–4435, doi:10.1021/acs.jpcc.0c11374.Skorikova, G.; Rauber, D.; Aili, D.; Martin, S.; Li, Q.; Henkensmeier, D.; Hempelmann, R. Protic Ionic Liquids Immobilized in Phosphoric Acid-Doped Polybenzimidazole Matrix Enable Polymer Electrolyte Fuel Cell Operation at 200 °C. Journal of Membrane Science 2020, 608, 118188, doi:10.1016/j.memsci.2020.118188.Rodenbücher, C.; Wippermann, K.; Korte, C. Atomic Force Spectroscopy on Ionic Liquids. Applied Sciences 2019, 9, 2207, doi:10.3390/app9112207.Rodenbücher, C.; Chen, Y.; Wippermann, K.; Kowalski, P.M.; Giesen, M.; Mayer, D.; Hausen, F.; Korte, C. The Structure of the Electric Double Layer of the Protic Ionic Liquid [Dema][TfO] Analyzed by Atomic Force Spectroscopy. International Journal of Molecular Sciences 2021, 22, 12653, doi:10.3390/ijms222312653. Figure 1

Two layer control strategy of an island DC microgrid with hydrogen storage system

In this paper, a two-layer hierarchical control strategy for an isolated DC microgrid with a hybrid energy storage system is considered. The DC microgrid studied is composed of a short-term battery energy storage system, long-term hydrogen-based energy storage system and renewable energy resources. The proposed control strategy, combines concepts of Interconnection and Damping Assignment Passivity-Based Control (IDA-PBC) as a primary level and Model Predictive Control (MPC) as a supervisory level. The IDA-PBC layer guarantees a correct power balance and ensures global stability according to Lyapunov theory, considering the non-linear behavior of the physical system. On the other hand, the MPC layer calculates the reference signals for the primary level, ensuring null stationary error in the desired variables. As known, it is important to keep the electrolyzer, the fuel cell and the batteries in a safe operating mode to increase their useful life and guarantee the quality of the hydrogen produced. In this sense, the benefits of MPC are exploited by considering system constraints in the controller design. The main objective of the two-layer control strategy is to ensure the supply of electrical energy to the loads and quality in the electrical variables of the network. Representative simulation results under demanding conditions verify the effectiveness of combining IDA-PBC and MPC for this class of problems.

Hierarchical model predictive control for islanded and grid-connected microgrids with wind generation and hydrogen energy storage systems

This paper presents a novel energy management strategy (EMS) to control a wind-hydrogen microgrid which includes a wind turbine paired with a hydrogen-based energy storage system (HESS), i.e., hydrogen production, storage and re-electrification facilities, and a local load. This complies with the mini-grid use case as per the IEA-HIA Task 24 Final Report, where three different use cases and configurations of wind farms paired with HESS are proposed in order to promote the integration of wind energy into the grid. Hydrogen production surpluses by wind generation are stored and used to provide a demand-side management solution for energy supply to the local and contractual loads, both in the grid-islanded and connected modes, with corresponding different control objectives. The EMS is based on a hierarchical model predictive control (MPC) in which long-term and short-term operations are addressed. The long-term operations are managed by a high-level MPC, in which power production by wind generation and load demand forecasts are considered in combination with day-ahead market participation. Accordingly, the hydrogen production and re-electrification are scheduled so as to jointly track the load demand, maximize the revenue through electricity market participation and minimize the HESS operating costs. Instead, the management of the short-term operations is entrusted to a low-level MPC, which compensates for any deviations of the actual conditions from the forecasts and refines the power production so as to address the real-time market participation and the short time-scale equipment dynamics and constraints. Both levels also take into account operation requirements and devices’ operating ranges through appropriate constraints. The mathematical modeling relies on the mixed-logic dynamic (MLD) framework so that the various logic states and corresponding continuous dynamics of the HESS are considered. This results in a mixed-integer linear program which is solved numerically. The effectiveness of the controller is analyzed by simulations which are carried out using wind forecasts and spot prices of a wind farm in center-south of Italy.

Layered Coaxial Nanowires Electrode (LCANE) for High Performance with Low Loading in Polymer Electrolyte Membrane Water Electrolyzer (PEMWE)

Polymer electrolyte membrane water electrolyzer (PEMWE) could play a key role in green hydrogen production from intermittent renewable energy sources, yet, the high loading of scarce precious metals hinders widespread commercialization. Innovative electrode designs that decrease the precious metal loading while maintaining high performance can be a significant step forward for the quicker adoption of hydrogen-based energy storage systems. Herein, we report a novel Layered Coaxial Nanowire Electrode (LCANE) composed of ionomer nanowires encapsulated by IrO2-decorated Pt nanofilms, which enables increased hydrogen production with decreased catalyst loading. By combining atomic layer deposition of Pt, ultrasonic spray of IrO2, and nano-extrusion of ionomer, the LCANE architecture enables improved in-plane conductivity, faster transport, and less agglomeration of catalyst. With a fraction of loading compared to conventional electrodes, LCANE demonstrates a promising way to decrease the loading of the PEMWE anode. Figure 1

An integrated energy analysis framework for evaluating the application of hydrogen-based energy storage systems in achieving net zero energy buildings and cities in Canada

The integration of hydrogen-based energy storage systems into urban residential buildings is a promising method to reduce urban greenhouse gas emissions and achieve clean energy supply. However, a comprehensive energy evaluation method that accurately reflects the system lacking. To address this gap, this study proposes a robust integrated energy analysis framework for evaluating the application prospect of hydrogen-based energy storage systems in urban residential buildings. The framework involves building energy analysis modeling, uncertain modeling, and energy management optimization modeling and provides comprehensive energy analysis results that fully consider urban characteristics. The study evaluates the economy, environment, and energy development potential of hydrogen-based energy storage systems in 20 Canadian cities. The results indicate that the implementation of hydrogen-based energy storage systems in residential buildings in these cities resulted in annual economic costs ranging from 10,682 Canadian dollars to 234,689 Canadian dollars, annual reduced carbon emissions ranging from 29 kg CO2e to 20,712 kg CO2e, and annual energy potential rate ranging from 45.28% to 223.92%. The study found that hydrogen storage has an economic advantage in hydrogen-based energy storage systems, whereas battery storage has environmental and energy potential advantages. The proposed energy analysis framework can provide techno-economic references for Canadian planners to plan a reasonable hydrogen roadmap for urban residential buildings.

Exploring Hydrogen-Based Energy Storage Systems for Canadian Residential Buildings: An Energy Evaluation Methodology

In recent years, integrating solar energy systems and hydrogen-based energy storage systems into residential buildings has shown promise in reducing urban greenhouse gas emissions and achieving clean energy supply. However, there is a lack of evaluation on the application potential of hydrogen-based energy storage systems in urban residential buildings. Therefore, a comprehensive energy evaluation method that considers urban building energy differences was implemented in 20 Canadian cities to evaluate the net-zero energy building status. The simulations were based on a typical residential building in North America. The results indicate that, for selected cities, the hydrogen-based energy storage system effectively addresses the seasonal energy mismatch and improves the energy self-sufficiency rate of urban residential buildings. These cities are classified as net-zero energy cities, nearly zero-energy cities, and non-net-zero energy cities based on their energy self-sufficiency rate. It is recommended to adopt hydrogen-only energy storage systems, hydrogen-electricity energy storage systems, and diverse renewable energy resources as integrated solutions to achieve net-zero emission buildings. The proposed energy analysis method can provide technical references for Canadian planners to plan a reasonable hydrogen roadmap for urban residential buildings.

Operating Hydrogen-Based Energy Storage Systems in Wind Farms for Smooth Power Injection: A Penalty Fees Aware Model Predictive Control

Smooth power injection is one of the possible services that modern wind farms could provide in the not-so-far future, for which energy storage is required. Indeed, this is one among the three possible operations identified by the International Energy Agency (IEA)-Hydrogen Implementing Agreement (HIA) within the Task 24 final report, that may promote their integration into the main grid, in particular when paired to hydrogen-based energy storages. In general, energy storage can mitigate the inherent unpredictability of wind generation, providing that they are deployed with appropriate control algorithms. On the contrary, in the case of no storage, wind farm operations would be strongly affected, as well as their economic performances since the penalty fees wind farm owners/operators incur in case of mismatches between the contracted power and that actually delivered. This paper proposes a Model Predictive Control (MPC) algorithm that operates a Hydrogen-based Energy Storage System (HESS), consisting of one electrolyzer, one fuel cell and one tank, paired to a wind farm committed to smooth power injection into the grid. The MPC relies on Mixed-Logic Dynamic (MLD) models of the electrolyzer and the fuel cell in order to leverage their advanced features and handles appropriate cost functions in order to account for the operating costs, the potential value of hydrogen as a fuel and the penalty fee mechanism that may negatively affect the expected profits generated by the injection of smooth power. Numerical simulations are conducted by considering wind generation profiles from a real wind farm in the center-south of Italy and spot prices according to the corresponding market zone. The results show the impact of each cost term on the performances of the controller and how they can be effectively combined in order to achieve some reasonable trade-off. In particular, it is highlighted that a static choice of the corresponding weights can lead to not very effective handling of the effects given by the combination of the system conditions with the various exogenous’, while a dynamic choice may suit the purpose instead. Moreover, the simulations show that the developed models and the set-up mathematical program can be fruitfully leveraged for inferring indications on the devices’ sizing.

Strategies for the Adoption of Hydrogen-Based Energy Storage Systems: An Exploratory Study in Australia

A significant contribution to the reduction of carbon emissions will be enabled through the transition from a centralised fossil fuel system to a decentralised, renewable electricity system. However, due to the intermittent nature of renewable energy, storage is required to provide a suitable response to dynamic loads and manage the excess generated electricity with utilisation during periods of low generation. This paper investigates the use of stationary hydrogen-based energy storage systems for microgrids and distributed energy resource systems. An exploratory study was conducted in Australia based on a mixed methodology. Ten Australian industry experts were interviewed to determine use cases for hydrogen-based energy storage systems’ requirements, barriers, methods, and recommendations. This study suggests that the current cost of the electrolyser, fuel cell, and storage medium, and the current low round-trip efficiency, are the main elements inhibiting hydrogen-based energy storage systems. Limited industry and practical experience are barriers to the implementation of hydrogen storage systems. Government support could help scale hydrogen-based energy storage systems among early adopters and enablers. Furthermore, collaboration and knowledge sharing could reduce risks, allowing the involvement of more stakeholders. Competition and innovation could ultimately reduce the costs, increasing the uptake of hydrogen storage systems.

Techno-economic assessment of hydrogen pipe storage in decommissioned wellbores sourced from surplus renewable electricity

Wellbore decommissioning is the final stage in the life cycle of any oil or gas well and involves placing acceptable well barriers to seal the wellbore. Operators have the obligation to decommission wells safely once they reach the end of their life. This study explores the prospects of repurposing near-to-decommission wellbores for pipe storage, forming a hydrogen-based energy storage system for containing hydrogen produced from surplus renewable electricity. It offers two pathways for hydrogen consumption, 1) Power-to-Hydrogen and 2) Power-to-Power. A conceptual design is presented to repurpose a wellbore into pipe storage to store hydrogen in its gaseous form. The storability of the pipe depends on pipe characteristics, including diameter and length as well as working pressure. Monte Carlo simulations are performed to calculate levelized cost of storage (LCOS) and levelized cost of hydrogen (LCOH) for the proposed method. The LCOS is in the range of 1.33 A$/(kgH2) and 1.66 A$/(kgH2). LCOH including the storage cost is obtained to be in the range of 5.22 A$/(kgH2) and 6.50 A$/(kgH2). This system can potentially integrate green hydrogen into local economies by managing decommissioning costs for the creation of a storage solution for green hydrogen.

Life cycle environmental analysis of a hydrogen-based energy storage system for remote applications

Energy storage systems are required to address the fluctuating behaviour of variable renewable energy sources. The environmental sustainability of energy storage technologies should be carefully assessed, together with their techno-economic feasibility. In this work, an environmental analysis of a renewable hydrogen-based energy storage system has been performed, making use of input parameters made available in the framework of the European REMOTE project. The analysis is applied to the case study of the Froan islands (Norway), which are representative of many other insular microgrid sites in northern Europe. The REMOTE solution is compared with other scenarios based on fossil fuels and submarine connections to the mainland grid. The highest climate impacts are found in the diesel-based configuration (1,090.9 kgCO2eq/MWh), followed by the REMOTE system (148.2 kgCO2eq/MWh) and by the sea cable scenario (113.7 kgCO2eq/MWh). However, the latter is biased by the very low carbon intensity of the Norwegian electricity. A sensitivity analysis is then performed on the length of the sea cable and on the CO2 emission intensity of electricity, showing that local conditions have a strong impact on the results. The REMOTE system is also found to be the most cost-effective solution to provide electricity to the insular community. The in-depth and comparative (with reference to possible alternatives) assessment of the renewable hydrogen-based system aims to provide a comprehensive overview about the effectiveness and sustainability of these innovative solutions as a support for off-grid remote areas.

A newly developed solar-based cogeneration system with energy storage and heat recovery for sustainable data centers: Energy and exergy analyses

There is a strong need and hence specific challenges attached to this for data centers to bring holistic energy solutions for better operation, control and management in a more cost-effective, efficient and environmentally benign manner. The current study develops and investigates a solar-based novel integrated system to generate electricity and hence provide cooling in a sustainable way. The proposed system includes a parabolic trough-type concentrated solar plant with a Rankine cycle, bifacial photovoltaic plant, proton exchange membrane (PEM) fuel cell, PEM electrolyzer, Cu-Cl thermochemical hydrogen production cycle, Li-Br absorption refrigeration cycle. In order to prevent solar intermittency, thermal and chemical-based energy storage systems are integrated as molten salt cold and hot thermal energy storage tanks and hydrogen-based energy storage systems. The heat is recovered by the Rankine cycle and the Li-Br absorption refrigeration cycle in order to generate electricity and to provide cooling. The overall system is analyzed with thermodynamic approaches from the energy and exergy points of view. For further, the overall system is analyzed with the hourly ambient data in a time-dependent analysis for a data center in Calgary, Alberta, Canada. For the average ambient conditions, the energy and exergy efficiencies of the overall integrated system calculated as 35.98% and 31.24%, respectively. At least 10% of the overall energy efficiency is exceeded during a total of 8091 h of the year, whereas the overall exergy efficiency is exceeded 10% during the 7726 h in a year. Further to note that there are challenges for such systems to bring a holistic solution.

Control of Hydrogen Based Energy Storage System for Hybrid Ac/Dc Microgrids

Control of Hydrogen Based Energy Storage System for Hybrid Ac/Dc Microgrids

Performance investigation of the hydrogen-based energy storage system employing high-pressure metal hydride pair

ABSTRACT The performance of hydrogen-based energy storage (HBES) systems is anticipated using a finite volume technique and thermal analysis with TiCrMn-MmNi4.15Fe0.85 as a linked metal hydride (MH) pair, obtained through screening. To understand the behavior of the materials during reactions, a set of governing equations is solved using the computational fluid dynamics (CFD) technique. The pressure concentration isotherms (PCIs) are predicted through numerical code and are used for numerical analysis. The performance of the HBES system is evaluated at the operating temperatures of 423 K, 403 K, 373 K, and 298 K as output, storage, regeneration, and ambient temperatures, respectively. The current HBES system has energy storage (ES) density of 136.74 kJ/kg and a coefficient of performance of 0.47. The total operation duration is obtained as 36 min, and it consists of two hydrogen exchange and two heat transfer processes.

Process dynamics in a hydrogen-based energy storage system

The BioGenerator is a technology that was recently invented and is used for the biological conversion of hydrogen to electricity. Its main application is in the re-electrification of hydrogen in hydrogen-based energy storage systems for the smoothing of the variability in wind and solar power generation. Therefore, BioGenerator operation is highly dynamic. The core of the BioGenerator is a bioreactor where principal microorganisms Leprospirillun ferriphilum oxidize Fe2+ to Fe3+. The dynamics of the process of energy storage affects the temporal characteristics of the bioreactor. The BioGenerator remains idle during the peaks of power generation of renewable power where Fe2+ remaining in the bioreactor is continuously consumed biologically. Likewise during the valleys in power generation Fe3+ is consumed electrochemically and Fe2+ accumulates. The effect of periodic interruption on the operation of the iron-oxidizing bioreactor was studied in this work. Our results show that idling of the BioGenerator for less than half a day has no negative effect on returning to the initial performance, while longer idling periods result in a small temporary reduction in bioreactor performance. Similar dynamics were observed in both stand-alone bioreactor as well as in a bioreactor incorporated in a complete BioGenerator system for hydrogen re-electrification. Additionally, operation of the closed loop BioGenerator system revealed hysteresis effects on the steady state bio-oxidation rate correctable with brief interruption of operation.

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.