| 摘要 | ��
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1. Background and Research Objectives
A fluctuation of the oil price in recent years causes an uncertain situation for an early advent of hydrogen economy. However, it is a common view that hydrogen economy will emerge as a core of the sustainable future energy system. Another issue for an early advent of hydrogen economy is the building of a cost effective infrastructure. Hydrogen is produced, transported, and stored until it is used by end-users. Accordingly, it is necessary to build a cost effective infrastructure through a systemic approach from production to application.
This study aims at providing an efficient hydrogen infrastructure construction plan to supplement shortcomings of the previous 2008 report "A Development of the Optimal Path for Transition into
Hydrogen Economy." The previous study focused on the construction of the optimal hydrogen supply system through a systemic approach from production to application with the assumption that the ratio of on-site and off-site hydrogen production is given. In this context, the main theme is to build up an efficient hydrogen infrastructure by taking a systemic approach of finding the optimal ratio of on-site and off-site hydrogen production in each stage of hydrogen economy. This study also derives the number and the locations of hydrogen fueling stations needed to follow the market introduction scenarios of fuel cell vehicles.
2. Methodology
This study adopts two approaches: First, hydrogen production system is categorized into central off-site and distributed on-site. Second, network theory to optimize the production mix of central and distributed hydrogen production. The main energy resources for a distributed hydrogen production are natural gas, electricity, oil, and renewable energy. In contrast, the main energy resources for a central hydrogen production are coal, nuclear power, biomass, by-product hydrogen, and renewable energy. Therefore, the mix of energy resources for hydrogen production varies with the mix of central and distributed production. This study derives the number and the locations of hydrogen fueling stations by regions and years according to scenarios on the hydrogen demands of the transportation sector. The scenarios are classified into the base case, the low demand case, and the high demand case. The 2008 study developed an integer programming model for the hydrogen supply system. The objective was to determine the schedule of the hydrogen supply locations and amounts that minimizes the total production and transportation cost. In this study the optimization model for constructing an efficient hydrogen infrastructure is formulated as a network theory problem. The network optimization algorithm is based
on the modified minimum spanning tree method that minimizes the total cost by connecting all sources and destinations effectively.
3. Major Findings and Policy Implications
Major findings of this study are as follow: First, the numbers of hydrogen fueling stations for the base case in 2030, 2035, and 2040 are 939, 3,329, and 8,649, respectively. The number of hydrogen fueling stations is expected to increase rapidly after 2030. By considering the current and the expected number of gas stations in 2040, a gas or LPG station will be replaced by a hydrogen fueling station. Second, the ratios of central hydrogen production for the base case in 2030, 2035, and 2040 are estimated as 35.7%, 72.2%, and 88.9%, respectively. The most hydrogen demand on the transportation sector will be supplied from distributed production until 2030. However, the ratio and the amounts of central production is expected to increase rapidly after 2031. Third, it is recommended that the hydrogen fueling station network should be starting from the major big cities in order to minimize the risk of hydrogen suppliers. This strategy is considered as maximizing the hydrogen supply range and minimizing the construction cost of hydrogen infrastructure. Lastly, the pipeline is considered as the most economic means of
delivering hydrogen, and the hydrogen pipeline will appear in 2030. The initial pipeline is expected to constructed in regions such as Seoul and some capital regions in 2030, and the full scale national hydrogen pipeline will be constructed in 2040 for the base case. For the lowdemand case the construction of the full scale hydrogen pipeline will be delayed 5 years compared with that of the base case. Therefore, it is necessary to develop the RD & D plan of central hydrogen production technologies by taking into account these time periods.
4. Suggestions for Further Studies
This study aims to building a cost effective hydrogen infrastructure by applying network theory. However, due to the limited resources in terms of time and relevant information, hydrogen transportation modes were confined to pipeline and cost analysis of hydrogen delivery was not fully conducted. In the future, more reliable analysis of hydrogen delivery will be possible based on the establishment of database. Second, this study focused on the establishment of the network of hydrogen fueling stations based on major big cities. However, we need to consider both hydrogen demand and supply potential for deciding the optimal locations of hydrogen fueling stations. Therefore, it is recommended that the optimal model of hydrogen infrastructure development should be based on the GIS(geographic information system).
Last, an in-depth analysis of economic and industrial impact for each demand sector might be recommended. Hydrogen can be used in the transportation, residential/commercial, industrial, and power generation sectors, it is necessary to build a cost effective hydrogen infrastructure by considering all hydrogen demand sectors. Also, it is necessary to establish the optimal hydrogen supply system through a systemic approach from production to application.
252 pages, 64 refs., 49 tabs., 22 Figs., Language: Korean |
