The State-of-the-Art Progress on the Forms and Modes of Hydrogen and Ammonia Energy Utilization in Road Transportation

Abstract

The crisscross progress of transportation and energy carries the migrating track of human society development and the evolution of civilization, among which the decarbonization strategy is a key issue. Traffic carbon emissions account for 16.2% of total energy carbon emissions, while road traffic carbon emissions account for 11.8% of total energy carbon emissions. Therefore, road traffic is a vital battlefield in attaining the goal of decarbonization. Employing clean energy as an alternative fuel is of great significance to the transformation of the energy consumption structure in road transportation. Hydrogen and ammonia are renewable energy with the characteristics of being widely distributed and clean. Both exist naturally in nature, and the products of complete combustion are substances (water and nitrogen) that do not pollute the atmosphere. Because it can promote agricultural production, ammonia has a long history in human society. Both have the potential to replace traditional fossil fuel energy. An overview of the advantages of hydrogen and ammonia, as well as their development in different countries such as the United States, the European Union, Japan, and other major development regions is presented in this paper. Related research topics of hydrogen and ammonia’s production, storage and transferring technology have also been analyzed and collated to stimulate the energy production chain for road transportation. The current cost of green hydrogen is between $2.70–$8.80 globally, which is expected to approach $2–$6 by 2030. Furthermore, the technical development of hydrogen and ammonia as a fuel for engines and fuel cells in road transportation is compared in detail, and the tests, practical applications and commercial popularization of these technologies are summarized, respectively. Opportunities and challenges coexist in the era of the renewable energy. Based on the characteristics and development track of hydrogen and ammonia, the joint development of these two types of energy is meant to be imperative. The collaborative development mode of hydrogen and ammonia, together with the obstacles to their development of them are both compared and discussed. Finally, referring to the efforts and experiences of different countries in promoting hydrogen and ammonia in road transportation, corresponding constructive suggestions have been put forward for reference. At the end of the paper, a framework diagram of hydrogen and ammonia industry chains is provided, and the mutual promotion development relationship of the two energy sources is systematically summarized.

Productive and Sustainable H2 Production from Waste Aluminum Using Copper Oxides-Based Graphene Nanocatalysts: A Techno-Economic Analysis

“…(5) An economic feasibility study was performed for a small town, Taiz, in Yemen, with a daily collection of waste aluminum of up to 432 kg/day. (6) The cost of H 2 produced by this method is competitive with water-splitting technologies, and the reaction was completed in 20 min. Furthermore, an increase in the production capacity can steeply reduce the production cost of H 2 gas.…”

“…It is the simplest known element and is a universally abundant gas, with the highest heating value among other conventional fuels, being three to four times higher than natural gas and gasoline. It is considered an ideal energy carrier that can be stored in all matter phases (gaseous, liquid, and solid) [5,6].…”

“…Although the current processing methods commonly use fossil fuels, there are sustainable methodologies suggesting high-potential H 2 storage systems, such as water, biomass, and hydrated metals, which are still at the research stage and require more investigation and manipulation [3][4][5][6][7][8][9]. Water-splitting, based on solar systems, using photocatalysts for H 2 production is widely investigated in the literature [10][11][12][13][14].…”