The first six months of 2017 have been good for the coal mining sector in the United States, China and India. According to data reviewed by the Associated Press, production in the three countries is up about 6 percent, or 110 Mt (121 million st) compared to the same period last year.

The three countries in the study are the three biggest users of coal in the world. The most dramatic change in coal use was in the United States which saw coal mining rise 19 percent in the first five months of the year, according to U.S. Department of Energy data.

The AP reported that the reasons for this year's turnaround include policy shifts in China, changes in U.S. energy markets and India's continued push to provide electricity to more of its poor, industry experts said. President Donald Trump's role as coal's booster-in-chief in the U.S. has played at most a minor role, they said.

While the news is good for coal miners now, the real question is if the growth is long-term.

The report from the AP notes that renewable energy continues to carve out a bigger slice of the energy pie. China now has more renewable energy than any other nation. Its Communist Party leaders have vowed to invest $360 billion in the sector through 2020.

India's government has said it needs no more coal-powered power plants and last month canceled 13.7 gigawatts in proposed plants, enough to power more than 10 million homes if the plants ran at full capacity. It has promoted renewables with a raft of incentives and declared that power from some solar installations should be used first when demand goes up.

In the United States, cheap natural gas, a growing appetite for renewable energy and stricter pollution rules spurred utilities to shut down or announce retirements for several hundred U.S. coal plants. U.S. utilities that invested heavily in alternatives are considered unlikely to revert to coal, meaning market forces and not Trump's politics will play the biggest role in determining the industry's future.

Still, the increase in production is welcome news to many in the coal sector.