Ammonia as an environmentally benign energy carrier for the fast growth of China

Abstract

In China, renewable energy is expected to account for a larger proportion of electric power systems although regional and intermittent characteristics have led to enormous unused wind and solar power stations in western and northern China. In the mean-while, there exists a large demand on energy in central and eastern areas. The energy storage capability of hydrogen makes it a significant medium for emerging energy storage systems. But the formidable challenge of hydrogen storage and long-distance transportation restricts its development. To address this issue, this paper proposes a scheme for an ammonia-based energy storage system in which ammonia, an environmentally benign hydrogen carrier, is expected to compromise the conflicts of renewable energy supply and consumption in China. By utilizing abandoned wind power and solar power, we get electrolyze water to generate hydrogen and get air to generate nitrogen. Compositing ammonia with hydrogen and nitrogen using Hubert's method also need much electricity. And the power stored in ammonia can be released in form of thermal energy or electricity when needed. This paper then presents some typical applications of ammonia that can meet people's needs of fuel, power, electricity, and zero-carbon fertilizer. The proposed scheme is particularly useful for storing discarded power in western and northern China in ammonia which can be transported and used in eastern regions without regional and seasonal restrictions. As an extra advantage, oxygen as a side product associated with the production of ammonia may play a significant role in oxygen-riched combustion plants.