*3.2. Fuel Cells—Hydrogen Conversion Technology*

Science has shown that there are two alternatives for sustainable energy supply: renewable sources and fuel cells—hydrogen-based energy—which will play a complementary role in ensuring global energy resource security [36].

By promoting the use of hydrogen-based energy technologies as clean energy technologies for stationary applications [48], at the level of local communities, industrial and commercial communities, the research topic in this field will help the practical development of sustainable and clean energy systems.

## 3.2.1. General Aspects
