Abstract:
Hydrogen energy can play a pivotal role in the energy transition and sustainable development. It is very urgent to optimize the energy structures and transition industries toward low-carbon solutions in recent years, particularly in the pursuit of carbon peaking and carbon neutrality. Fortunately, bio-methanol cracking hydrogen production can be expected to offer cost-effectiveness and scalability among the emerging technologies. However, it is still lacking in the environmental impact and economic assessment. In this study, a systematic quantitative assessment was conducted on the environmental impacts at each stage of the life lifecycle. A dynamic economic evaluation was also coupled for the decision-making and strategic deployment of bio-methanol cracking hydrogen production. A case study was selected as the medium-sized plant of methanol cracking hydrogen production in Wuxi City, Jiangsu Province, China. A comprehensive evaluation of the integrated system was selected to facilitate the environmental and economic performance. A life cycle model was developed to assess the environmental impacts. The potentials of environmental impacts were then calculated at each stage. Furthermore, some indicators were determined after economic evaluation, in order to balance the overall environmental footprint and the economic feasibility of the system. The results indicated that the hydrogen production stage contributed to the most significant environmental impacts, accounting for over 70% of categories, such as acidification potential (AP), abiotic depletion potential (ADP), and human toxicity potential (HTP). Notably, the HTP category was accounted for as much as 90.47%. The methanol production and transportation stages were also identified as substantial contributors to the environmental impacts. The ADP, HTP, and global warming potential (GWP) contributed the most to the overall environmental impact. While the least contribution was from the ozone depletion potential (ODP). Sensitivity analysis showed that the effective strategies greatly contributed to the minimum fuel consumption during methanol transportation. Negative environmental impacts were then mitigated to reduce the electricity usage in hydrogen production. The carbon emissions of the life cycle varied between 0.71 and 12.18 kg/kg , depending on the stage and scenario. Among the contributing factors, the bio-methanol production mode shared the most significant influence on the carbon emissions of the life cycle. Hydrogen energy was also used to reduce the emissions during methanol transportation. The costs of the integrated system were composed of the raw materials expenses, fixed capital investment, as well as operation and maintenance costs. While its revenue primarily stemmed from the hydrogen fuel sales. The economic indicators were obtained, with a payback period (PBP) of 12.16 years, a net present value (NPV) of 2.118 7 million yuan, and an internal rate of return (IRR) of 13%. Strong profitability, liquidity, and favorable economic performance were achieved in the bio-methanol cracking hydrogen production. Key influencing factors on the economic feasibility included raw material costs, carbon pricing, and hydrogen energy prices. The NPV ranged from -5.68×10
7 to 8.64×10
7 CNY in the various scenarios. Particularly, the economic competitiveness of the system was significantly enhanced in the scenarios with the higher hydrogen energy and carbon prices. The hydrogen energy prices enhanced the revenue potential of the system. While the higher carbon pricing also provided strong economic incentives for low-carbon technologies, further improving its financial viability.