Beijing built only four charging spots for electric-powered city buses in the last year, falling far short of its target of 172 piles, and modified less than 10 percent of the buses it had planned to make more environmentally friendly.

The National Audit Office, China's top auditing authority, on Wednesday publicized the unspent funds allocated to governments at all levels as well as unmet targets of government projects.

Beijing's government had planned to modify 2,500 buses to make them more environmental friendly, but work was completed on only 194 vehicles, mainly due to insufficient coordination of government departments and the lack of an efficient authority to organize the work, the office said.

China issued guidelines this month to ensure the construction of 5 million charging spots by 2020.

In five years, China intends to have nearly 12,000 large charging stations, an increase from 780 at the end of 2014, including 3,850 for public buses, 2,500 for taxis, 2,450 for special vehicles such as sanitation cars and 2,400 integrated charging stations for public usage.