Techno-Economic Analysis of a Novel Hydrogen-Based Hybrid Renewable Energy System for Both Grid-Tied and Off-Grid Power Supply in Japan: The Case of Fukushima Prefecture

Abstract

After the Great East Japan Earthquake, energy security and vulnerability have become critical issues facing the Japanese energy system. The integration of renewable energy sources to meet specific regional energy demand is a promising scenario to overcome these challenges. To this aim, this paper proposes a novel hydrogen-based hybrid renewable energy system (HRES), in which hydrogen fuel can be produced using both the methods of solar electrolysis and supercritical water gasification (SCWG) of biomass feedstock. The produced hydrogen is considered to function as an energy storage medium by storing renewable energy until the fuel cell converts it to electricity. The proposed HRES is used to meet the electricity demand load requirements for a typical household in a selected residential area located in Shinchi-machi in Fukuoka prefecture, Japan. The techno-economic assessment of deploying the proposed systems was conducted, using an integrated simulation-optimization modeling framework, considering two scenarios: (1) minimization of the total cost of the system in an off-grid mode and (2) maximization of the total profit obtained from using renewable electricity and selling surplus solar electricity to the grid, considering the feed-in-tariff (FiT) scheme in a grid-tied mode. As indicated by the model results, the proposed HRES can generate about 47.3 MWh of electricity in all scenarios, which is needed to meet the external load requirement in the selected study area. The levelized cost of energy (LCOE) of the system in scenarios 1 and 2 was estimated at 55.92 JPY/kWh and 56.47 JPY/kWh, respectively.

Comparative Analysis of Circular and Square End Plates for a Highly Pressurized Proton Exchange Membrane Water Electrolysis Stack

“…Both sides remained after the topology optimization; therefore, the side-cut shape differs from that in Figure 4a. Based on the topology optimization depicted in Figure 4, the four parameters were derived as follows: (1) volume removal between the bolts, (2) volume removal at the bottom, (3) round of sector form at the top, and (4) top center cut depth.…”

“…The order of the removed parameters is as follows: the first letter from the left is the bolt, the second letter is the bottom side, the third and fourth digits are the round radius, and the fifth and sixth digits are the thickness. The first letter is the symbol "C" in Figure 4a with a red circle when completely removed, the symbol "I" with a red Based on the topology optimization depicted in Figure 4, the four parameters were derived as follows: (1) volume removal between the bolts, (2) volume removal at the bottom, (3) round of sector form at the top, and (4) top center cut depth.…”

“…Based on the topology optimization of the square end plate depicted in Figure 4c, three parameters were derived: (1) volume removal between the bolts, (2) fillet formation, and (3) thickness reduction of the top region. Before proceeding with the parametric stress and strain analysis derived from the topology optimization of the square end plate, seven types were designed like the circular end plate, as illustrated in Figure 5b.…”

“…The part where nothing has been removed for the fifth and sixth digits was designated "00," the portion to be removed to a depth of 10 mm was designated "10," and the portion to be removed to a depth of 20 mm was designated "20." Based on the topology optimization of the square end plate depicted in Figure 4b, three parameters were derived: (1) volume removal between the bolts, (2) fillet formation, and (3) thickness reduction of the top region. Before proceeding with the parametric stress and strain analysis derived from the topology optimization of the square end plate, seven types were designed like the circular end plate, as illustrated in Figure 5b.…”

“…Air pollution, carbon dioxide emissions, and fine dust problems have attracted attention due to the use of fossil fuels. Proton exchange membrane water electrolysis (PEMWE) can produce hydrogen without emitting pollutants such as carbon dioxide, in contrast to fossil fuels [1]. If electricity is produced by renewable energy technology, hydrogen from water electrolysis can be stored in an environmentally friendly manner [2].…”