Table 4 Yearly outputs of journals, patents, technology, and business from green hydrogen projects
From: A study on a political system for the advance in green hydrogen technology: a South Korea case study
| Â | 2017 | 2018 | 2019 | 2020 | 2021 | Total |
|---|---|---|---|---|---|---|
Journals | 481 | 596 | 515 | 668 | 998 | 3258 |
Patents | 257 | 232 | 262 | 208 | 31 | 990 |
Technology | 15 | 12 | 11 | 31 | 3 | 72 |
Business | 12 | 8 | 15 | 3 | 1 | 39 |