Hydrogen Assisted Renewable Power System

Renewable Energy 30 (2005) 1525–1540 www.elsevier.com/locate/renene

An integrated system framework for fuel cell-based distributed green energy applications S.H. Wu*, D.B. Kotak, M.S. Fleetwood Institute for Fuel Cell Innovation, National Research Council Canada, 3250 East Mall, Vancouver, BC, Canada V6T 1W5 Received 16 July 2004; accepted 9 November 2004 Available online 28 December 2004

Abstract The environmental pollution and diminishing conventional fuel sources and global warming problems make it more attractive for considering renewables as alternative energy sources, such as solar, wind and micro hydro, etc. Recent advances in hydrogen and fuel cell technologies further facilitate these energy options to supply electrical power to various communities. Hydrogen fuel cell systems coupled with renewable energy sources stand out as a promising solution. This paper presents an integrated system framework for fuel cell-based distributed energy applications. Five components are included in this framework: a physical energy system application, a virtual simulation model, a distributed coordination and control, a human system interface and a database. The integrated system framework provides a means to optimize system design, evaluate its performance and balance supplies and demands in a hydrogen assisted renewable energy application. It can either be applied to a distributed energy node that fulfills a local energy demand or to an energy-network that coordinates distributed energy nodes in a region, such as a hydrogen highway. The proposed system framework has been applied in the first phase of our multi-phases project to investigate and analyze the feasibility and suitability of hydrogen fuel assisted renewable power for a remote community. Through integration with an available renewable energy profile database, the developed system efficiently assists in selecting, integrating, and evaluating different system configurations and various operational scenarios at the application site. The simulation results provide a solid basis for the next phase of our demonstration projects. Crown Copyright q 2004 Published by Elsevier Ltd. All rights reserved. Keywords: Fuel cell; Hydrogen; Renewable energy; Simulation; Coordination and control

* Corresponding author. Tel.: C1 604 221 3000; fax: C1 604 221 3001. E-mail address: [email protected] (S.H. Wu). 0960-1481/$ - see front matter Crown Copyright q 2004 Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.renene.2004.11.006

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1. Background The replacement of environmentally unfriendly fossil fuels with green energy resources play a fundamental role in resolving environmental pollution and global warming problems. Diminishing conventional fuel sources make it more attractive for considering renewable energy as an alternative energy source, such as solar, wind and macro hydro, and biomass, etc. However, due to its inherent nature of lacking controllability and availability, renewable energy by itself cannot meet the full requirements of a load. The recent advances in hydrogen and fuel cell technologies have enabled hydrogen fuel cell as a new energy option for supplying electrical power in commercial and residential buildings, and even for remote off-grid communities. Hydrogen, as an energy carrier, provides a good opportunity for effectively utilizing renewable energies in either a distributed or a centralized way. As one of the fundamental concepts of the emerging hydrogen economy, hydrogen assisted renewable power becomes an important alternative in producing electrical power in a clean and efficient manner and will make renewable energy more practical and mainstream in the future. During the past few years, a number of researchers and developers have been engaged in adopting renewable energy and hydrogen fuel cell technology to supply electrical power. For example, Santarelli et al. developed a simulation program for analyzing a PVhydrogen system feeding energy to a residential building [1]; Meurer et al. presented a PHOEBUS—an autonomous supply system with renewable energy [2]; E1-Shatter et al. designed and simulated a hybrid PV/fuel cell system [3]; Iqbal introduced a modeling and simulation system for a wind fuel cell hybrid energy system [4,5]; McIlveen-Wright et al. discussed the wood-fired fuel cells in various buildings and an isolated community [6,7]. A hybrid optimization computer model for electric renewables named HOMER was developed at NREL since 1994 [8]. The worldwide fuel cell installation for stationary application can also be found at Ref. [9]. The continuing developments and demonstrations of fuel cell and hydrogen technologies set the stage for further emission reduction initiatives moving forward. The government of Canada, through the h2EA program [10], is committed to working in partnership with industries to build a solid ‘hydrogen team’ and foster the development and early introduction in the Canadian market place of hydrogen and hydrogen-compatible technology. The recent announcements of California Hydrogen Highway [11] and BC Hydrogen Highway projects [12] promote the hydrogen fuel cell applications from individual energy nodes to an integrated energy network. It is a challenge to build such a scalable simulation system able to provide an effective, efficient and economical way to facilitate the system design and engineering analysis so as to validate and make ready the techniques for an industrial application. Based upon our previous research and expertise on holonic design and operational environment [13,14] under the IMS-HMS project [15], we propose an integrated system framework for fuel cell-based distributed green energy applications. We describe its energy node level application in one of our multi-phases industrial projects as well as an application in a hydrogen highway prototype project. In this paper, the integrated system framework for green energy applications scalable from energy device, energy node to energy network applications is presented. Section 2 outlines the simulation system architecture and components. Section 3 presents

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application examples using this simulation system both in our industrial project and prototype project. The future perspective and concluding remarks are given in Section 4.

2. System architecture As shown in Fig. 1, there are five major components (i.e. physical energy system, simulation, database, coordination and control and human system interface) in the proposed system architecture, whose application is scalable from energy devices, energy node to energy network. 2.1. Scalable applications Energy devices. The basic elements in the proposed system architecture are energy devices (sub-system). Three essential sub-systems that need to be dealt with are the energy generator including fuel cell or any other generating devices; the hydrogen storage vessel and the electrolyzer. These devices act as autonomous components in the integrated framework. The component-based system design make it free to add any other devices, for example, a solar panel in a PV-Fuel Cell hybrid system can be easily added as a standard device into the system when required. When evaluating the system performance, each device in the system can also be assessed separately in an integrated application. This modular approach easily accommodates the modification of an operational environment or a system reconfiguration. Energy node. It is the interconnected power generation technologies (or other individual application, such as hydrogen fuel cell car fuelling station) to provide electric

Fig. 1. System architecture.

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power or other energy supply services at a site closer to customers. The application at a node can be a backup power system (or a UPS), a hybrid-electrical power system integrated with renewable power, a distributed generation system for buildings or a hydrogen generator and fuelling station for hydrogen fuelled cars. Energy network. The independent, cooperative and loosely integrated energy nodes distributed in a certain geographical region form an energy network. One of the typical applications of the energy network concept is the recently announced BC Hydrogen Highway—a network of green communities leading sustainable region and road to the vision of a hydrogen economy. There are several different types of energy node applications included in this energy network: mobile, commercial and light industrial application at Finning site; mobile and residential application at UBC and NRC site; mobile and stationary application at airport and applications for remote community, recreational and commercial application at Whistler, etc. Built on the modular approach, the proposed system architecture is open and flexible and scalable to be applied to applications from device level to the network application level. 2.2. Distributed coordination and control As noted by EPRI Perspectives on the future, the increasing need of smaller, cleaner, widely distributed generators—combustion engine, fuel cells, wind turbines, photovoltaic installations will be advancing electronic controls: these will be absolutely essential for handling the tremendous traffic of information and power that such a complicated interconnection will bring. On the information side, monolithic, centrally located control systems in charge of system coordination cannot scale economically to meet the demands imposed by such systems. The solution is to design communication and control systems matched to the distributed, multi-participant, and dynamic nature of distributed resource management [16]. Coordination and control of the different energy devices within an energy node or coordination and control of each energy nodes within an energy network in a distributed manner are among the key issues needed to be addressed. In this proposed system framework, software agents—holons [13], are adopted for the responsibility of distributed coordination and control. An autonomous holon is viewed as one that can reason and plan a solution strategy once a task is delegated to that holon. It also has the ability to migrate across network and carry their data and execution state with them. The autonomy and migration feature of holons make them are well suited for distributed problem-solving applications as encountered in distributed energy system applications. A holon in a holarchy is characterized by autonomy and cooperation generally consists of a physical component and an informational component. The overall system objective is achieved by holarchy that is composed of basic holons or recursive holons that may also be another holarchy. As seen in Fig. 2, the relationship of energy nodes and energy devices in an energy network is well represented by holons (energy device holon and energy node holon) in a holarchy (energy network). The communication and coordination within an application (either an energy network or an energy node) are conducted through a concept

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Fig. 2. Holonic coordination and control in an energy network.

of Cooperation Domain (CD) that includes a physical infrastructure for communications and facilities for coordination, data storage and other communication facilities. The operational activities of an energy device in the virtual simulation environment are controlled by the agent-based holonic coordination and control system. Each autonomous energy device has its own corresponding holon running on one or more computers in a network with the proprietary TCP/IP based protocol. An energy device holon acts as the controller and proxy of the individual physical energy device at an energy node, and links to its corresponding virtual energy device implemented in the simulation environment. Energy device drivers in the simulator are implemented as individual ‘logics’ that are used to simulate the system operations. The advantages of this structure is that once the holonic coordination and control strategy is verified in the virtual simulation environment, it can be easily applied to the corresponding physical energy system applications. 2.3. Virtual system simulation Simulation is a faster, safer and cheaper approach to demonstrate and validate the proposed design and various operational scenarios of a physical system. Through modeling these physical energy devices in each energy node, a ‘what–if’ analysis can be conducted to assist the system designer in evaluating and anticipating the system’s efficiency, capacity, cost, scalability, reliability, and availability before the real implementation of a physical energy system. As indicated in Fig. 1, in the proposed

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system framework, a simulation model runs based upon a database and a holonic coordination and control model. The database provides the real load profiles of demands, the parameters of individual energy devices, and the available renewable energy profiles at a site if renewables is required, etc. while the coordination and control model provides operational logics and control for each energy devices/energy nodes in an energy application. Based on our standard integration interface among different components developed before [14], either a 2D simulation environment or a 3D simulation model can be adopted to emulate the physical energy system operations, predict their performance and validate the proposed system design and logics. A 2D simulation was developed in the first place and adopted in one of our industrial projects as described in the first case in Section 3. A more generic 3D simulation model using QUESTe [17] has now been developed to extend its application scope and functionalities. The integration with a 3D simulation model is verified by the prototype project (second case) described in Section 3. 2.4. Database The essential data for running the simulation model are collected, organized, and stored in a database. The information stored in the database includes: † † † † †

Available renewable energy profiles at each specific application node. Demand load profile of the communities or buildings where the system applies. Scalable requirements of applications; Physical data of energy devices, such as dimension, weight, emissions, capital cost, etc. Operating data of energy devices, indicating parameters such as capacities and throughput, hydrogen delivery pressure and temperature, operational and maintenance cost, heat rate, etc.

The data are acquired in various ways: from commercial device suppliers, device testing and evaluations, and device modeling. The Microsoft SQL Server 2000 is adopted and a database agent is implemented for the database’s integration within the system framework. A preliminary database has been established for one of our industrial projects and used for running the simulation model applied in the project as described in Section 3. 2.5. Physical system A physical system is a real-world implementation of the virtual system model verified in the simulation environment. Based on the basic system elements—energy devices, a physical system can either be an energy node application or an application at energy network level. The devices included in a physical energy system depend on its applications. As in one of our industrial projects (the first case in Section 3), five major physical devices are considered in a hydrogen assisted renewable power system at a energy node level: renewable energy sources; hydrogen generator (i.e. electrolyzer); hydrogen storage vessel, fuel cell system and electrical load; while in the second case, the major devices considered in the hydrogen highway infrastructure are the hydrogen

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fuelled cars and hydrogen fuelling station including hydrogen storage, dispenser and generator. Prior to the physical implementation, a system simulation model will be established to simulate the different design options and various operational scenarios. Therefore, the system design and operational logic can be anticipated, evaluated and optimized for the engineering analysis and implementation. 2.6. Human system interface The role of the human system interface herein is twofold, the first is to initialize the energy system design configuration at each energy node and dynamically control the system changes when the system simulation is running to make ‘what–if’ analysis; the second role is to provide a remote monitoring and control interface for an individual energy device. With the support of human system interface, the corresponding holon performs the action of aggregating and coordinating the operations of individual devices from different vendors. Presently, the human system interface has been developed for the system configuration and monitoring of system operations and performances. With the further development and integration with a 3D simulation model, a web-based human system interfaces is being developed and incorporated into this system framework for energy network applications.

3. Implementation and applications The proposed system framework has been being developed and applied in our projects. The first case given below, details an energy node level application in one of our industrial projects; while the second case demonstrates the verification of the integration with a 3D simulation model in a hydrogen highway prototype project. 3.1. Case 1: HARP—hydrogen assisted renewable power system In order to investigate the viability of making renewable energy more practical and mainstream through the use of hydrogen-based electricity systems, the National Research Council Canada, Institute for Fuel Cell Innovation (NRC-IFCI) with its industrial partner jointly conducted a feasibility study as the first phase of a multi-phase project —HARP. The study assessed the application of hydrogen and fuel cell technologies as a more sustainable alternative for improving the quality of electricity supply to remote, off-grid communities. The objective of HARP is to offset the diesel output and eventually replace the conventional fossil-fuelled generators with hydrogen fuelled power generation systems in remote off-grid areas. The proposed simulation system was developed and applied in the feasibility study phase of HARP project. 3.1.1. Background Like most other remote, off-grid communities, the pilot site selected for HARP also use renewables (small hydro) with a standby and backup fossil-fuelled Internal Combustion

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Engine (ICEs) as electricity supply. This kind of energy system provides reliable power, but with its inherent challenges. The small-hydro renewables has the ability to provide firmer power, but has not been developed to its full capacity because of the nature of serving only a local load. The economics for developing the renewable energy source to meet the local peak power demand is unwarranted. Presently, diesels are used as backup powers to provide the necessary reliability, but increase the environmental and financial cost that is undesirable. Half of the diesel generator sets has been rated as having poor fuel efficiency. Analyses of the historical water flow data and local load indicated that there are many periods where the load requirement is much lower than the generating total potential capacity of small hydro, particularly at night. In addition, the diesel generator set must also be spinning with enough reserve to handle sudden load increases (the capacity of the small hydro is often exceeded during the operation of a local factory which creates occasional power demand spikes. The diesel generation set is used for a standby power to provide excess capacity when the load demand exceeds the capacity of the small hydro). All of these leave spare power that goes unused and provide an opportunity to capture and store this extra energy by generating and storing hydrogen. Hydrogen, as an energy carrier, has the potential for enhancing the power supply quality of renewables and is a cleaner and potentially cost effective alternative to diesel fuel. Onsite generation and the stable nature of hydrogen also avoid the transport costs and the deregulation issues associated with diesel. In the HARP project, a hydrogen energy system is proposed and evaluated as the primary solution for resolving the existing off-grid power generation issues. The major devices considered in the hydrogen energy system are electrolyzer, hydrogen storage tank and hydrogen electricity generator (both fuel cell system and H2ICE are considered). Powered by a source of electrical power generated from the small hydro, the electrolyzer converts water into oxygen and hydrogen gas. The oxygen is released to the atmosphere and the hydrogen is stored in the hydrogen storage tank. When required, the power generation unit recombines the hydrogen and oxygen from the air into water, generating DC current plus heat in the process. Fig. 3 illustrated a process flow chart of the system. 3.1.2. Exceeded renewable energy In this project, the ‘spilled resource’ (extra renewable energy) is considered to be the amount of the extra water available that is not presently used for generation. The flow required to run the hydro turbine at its maximum capacity is around 4 cm/s, equivalent to 2000 kW generation. If the creek inflow is greater than the flow though the hydro turbine, but less than 4 cm/s, the difference is considered to be the lost generation potential or spilled resource. The quantification of the renewable spill resource is a task involving many variables and operating constraints. However, for this feasibility study, the following formula is used to estimate the renewable spilled resource potential: Inflows converted to generating potential K Hydro generation Z Renewable spilled resource

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Fig. 3. Schematic of HARP system.

Fig. 4 shows a graphical representation of the available spilled resources in a typical summer day. The historical available renewable energy profile is captured and stored in the database. 3.1.3. Component selection and system options Electrolyzser. An electrolyzer is a hydrogen generation device that converts water into hydrogen and oxygen. In this model, whenever surplus power is generated, hydrogen is produced via the electrolyzer. There are two types of electrolyzers, which are suitable for this application and available on the market, that are considered for this project: the alkaline electrolyzer (IMET series) from Stuart Energy [18] and the proton exchange membrane (PEM) electrolyzer from Hydrogenics [19]. As described in the followed section, both the 15 and 30 N m3/h electrolyzers are evaluated by a simulation mode in this feasibility study.

Fig. 4. Generation profile and available spilled renewable resource in a typical summer day.

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Power generation unit. The power generation units considered in this project are hydrogen fuel cell and H2ICE. Presently, there are several different fuel cell types in varying stages of development. They are differentiated by their electrolyte and operating temperatures as PEM fuel cell, phosphoric acid fuel cell (PAFC), molten carbonate fuel cell (MOFC) and solid oxide fuel cell (SOFC) [20]. Based on the requirements of the HARP project, the high-temperature fuel cells (PAFC, SOFC and MCFC) are ruled out as near-term options because they require a long period of start time and are designed for continuous operations rather than daily cycling as required by this application. In addition, they are also mainly fuelled by natural gas rather than pure hydrogen. PEM fuel cells, as they are fuelled by pure hydrogen, operate at a low temperature and can be used for daily cycling applications, are considered in this project. Two currently available PEM fuel cells, i.e. Ballard Nexae PEM fuel cells [21] and Hydrogenics PEM fuel cell [19] are evaluated in this feasibility study. As an alternative to a fuel cell, a H2ICE [18] is also considered in this application as an option because of its very good cycling properties and its very low near-term capital cost relative to the current cost of fuel cells. This leaves a cost ‘window of opportunity’ while fuel cell costs decline as the technology improves. Hydrogen storage. Storage is one of the toughest technical challenges facing the hydrogen and fuel cell industry. Based on the current technology, cost and other factors, neither the liquid hydrogen storage nor the metal hydride storage is recommended for this project. The recommended option is to store hydrogen as pressurized gas. Both the lowpressure and high-pressure hydrogen gas storages are considered in this project, and the low-pressure storage is recommended because it has the advantage of lower coupling costs between the electrolyzer and the storage tanks. In addition, there is usually adequate space available for relatively inexpensive multiple or large storage tank at most remote communities. Based on above components selection, several system configurations with different components options are recommended as solutions for HARP project. The technical parameters of the components with cost information are incorporated into the database. As the commercial requirements for commercial equipment providers is confidential, the system options, without detail parameters, are listed here as: Option 1: 50 kW Hydrogenics package. This option includes a hydrogenics 180 kW (30 N m3/h) PEM electrolyzer, compressor, high-pressure hydrogen storage (400 bar) Hydrogenics 50 kW PEM fuel cell. Option 2: 50 kW Composite system with Ballard Power Nexae Fuel Cells. This option includes Stuart Energy 150 kW (30 N m3/h) alkaline electrolyzer, low-pressure (25 bar) hydrogen storage vessel from Enermax Fabricators, Ballard 54 kW PEM fuel cell power plant. Option 3: 50 kW Composite system with Hydrogenics Fuel Cell. Option 3 is basically the same as Option 2 except the Hydrogenics 50 kW fuel cell in place of the Ballard Nexae. Option 4: 100 kW Stuart Energy Package: this package consists of Stuart Energy 150 kW (30 N m3/h) alkaline electrolyzer, compressor, low-pressure (17 bar) hydrogen storage tanks and a Ford 100 kW H2ICE Genset

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The evaluation criteria of these options include power output capacity, renewable energy availability and cost. 3.1.4. Implementation and results A 2D simulation model was built and applied at this energy node. The coordination and control for devices at this node were centrally implemented but scalable to a distributed application because of its agent-based open system structure. This simulation model dynamically accepts historical generation and water profiles stored in the database and computes the amount of hydrogen produced on an hourly basis. The modeling process estimates (1) The hourly excess power available from the renewable hydro-based on year 2000 generation profile and the 50th percentile inflows for the period of record. (2) Fuel cell or H2ICE operation: (a) The fuel cell operation mode: fuel cell will not generate if diesels are nonoperational. The diesels not being operational indicate that the electrolyzer is running off extra generating capacity at the small hydro. At this time hydrogen is being stored for use in peak periods to offset diesel operation. (b) The fuel cell is triggered either at a specific time if diesels are operational. If the diesels are not operational at the fuel cell trigger time, the fuel cell will wait for a specific time period for the diesels to start. (3) The power that the electrolyzer would need when generating or in standby mode. Fig. 5 shows the human system interface and Fig. 6 captures the real time input and output data for the summer month in 2002 and the storage fluctuations, electrolyzer operation, fuel cell operation, and diesel generation profiles. The complexity of the model for this feasibility study distinguishes between generator technologies but did not distinguish between electrolyzer technologies. It does not distinguish between the different fuel cell suppliers either. The other parameter in the model is the electrolyzer size (30 and 15 N m3/h). Four scenarios are constituted for the model simulation as indicated in Table 1.

Fig. 5. Human system interface.

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Fig. 6. A summer month profile.

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Table 1 Four HES scenarios for model simulation Scenario

1

Electrolyzer (N m3/h) Generator (kW)

Size I (30) ICE (100)

2

3

4

Size II (15) PEMFC (50)

ICE (100)

PEMFC (50)

Table 2 presents the simulation results for the different seasons that year. As expected, the H2ICE scenario recovered the most hydroelectric power because of its bigger generating capacity (100 vs 50 kW of a fuel cell). Regarding the fuel cell options, the 30 N m3/h, electrolyzer-fuel cell option is only restricted by the hydrogen storage and the maximum runtime allowance of the fuel cell. If these restrictions are relaxed, more power is available. There is enough hydrogen produced throughout the year 2002 to run either ICE or the PEMFC at 100% if the seasonal storage is available. In addition, as a 150 kW buffer capacity allowance is included in this simulation, disregarding this buffer would significantly increase the generation potential. The simulation result shows that it is technically feasible to adopt a hydrogen energy system to offset the diesel output at the selected pilot site. In addition, compared to the scenario using hydrogen fuel cell as the generation system, the H2ICE scenario has a lower capital cost but a higher maintenance cost and with larger hydrogen storage tanks. All of the information provides a solid basis for the engineering design and analysis. 3.2. Case 2: hydrogen highway infrastructure Presently, a 3D simulation model is being integrated into the system framework. In the prototyping phase of this hydrogen highway infrastructure project, the proposed integrated system framework is implemented and the integration structure with a 3D simulation model is validated. The major objective of the first phase is to verify the proposed system structure and technologies while the second phase will focus on modeling and simulating a hydrogen fuelling station that will be physically built at our institute—one node on the BC Hydrogen Highway. This section will brief the first phase implementation of the on-going project. 3.2.1. System description A prototype hydrogen highway with a number of hydrogen fuelling stations is implemented in a 3D simulation environment A number of hydrogen fuelled cars run on the hydrogen highway. The assumed objective is to seek a feasible layout of the hydrogen fuelling stations on the highway. 3.2.2. Implementation In order to meet the distributed and mobile requirements by hydrogen fuel car or fuelling stations, the coordination and control model is implemented as an agent-based holonic system using JADEe [22]. Each entity controller is implemented as JADEe agent that integrates with the virtual entity in the simulation environment to form a holon.

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Table 2 Simulation result Average (kWh/day) Type I electrolyzer

Summer Winter Spring/fall Year

Type II electrolyzer

ICE

FC

ICE

FC

423 167 283 313

225 133 176 195

247 111 165 188

225 133 176 186

Each holon is autonomous and has the responsibility of maintaining its local knowledge and keeping its neighbor holons informed once something changed. Driven by the external holonic coordination and control system, a 3D simulation model using QUESTe [17] is adopted to emulate system activities and validate the external control logic. Drivers of each entity in the 3D simulator are implemented as individual ‘logics’ that are used to simulate the system operations. The human system interface is embedded in the simulation interface, through which a system layout design is loaded and corresponding holonic agents are automatically created. The different system configuration is stored in a database utilizing the Microsoft SQL Sever 2000 database. Fig. 7 illustrates the integration of the different components and Fig. 8 captures the simulation interface and a zoom of a fuelling station node on the hydrogen highway. 3.2.3. Next step As one of the hydrogen highway nodes, a set of photovoltaic panels and a hydrogen fuelling station with hydrogen generation will be built at our institute, which is also the home to the hydrogen fuelled cars demonstration. Prior to the physical implementation, the proposed integrated simulation system tool is being expanded and will be used to

Fig. 7. Integration and implementation of the system components.

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Fig. 8. Simulation of hydrogen highway and a fuelling station node.

simulate system design and activities, and evaluate the design options, efficiency, capacity and scalability of this energy node.

4. Concluding remarks This paper presents an integrated system framework for fuel cell-based distributed green energy applications. Five components are proposed in this integrated system framework, namely, coordination and control system, virtual simulation environment, physical energy system, database and human system interface. The proposed architecture and integration technology were validated in a prototype project and applied in one of our industrial applications. As a promising means for future clean energy supply, hydrogen fuel cells have great potential in the emerging hydrogen economy. Our present research work in integrated system framework for distributed energy is still at the preliminary stage. Based on the system architecture and technologies used in this system, our ongoing development will focus on its application on two energy nodes on the hydrogen highway: this first is a green energy village including a hydrogen fuel cell and PV powered commercial building and a fuel cell powered transportation system in the village; the second one is the energy node at our institute where the hydrogen fuelling station plus PV and hydrogen generator will be implemented.

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