It may have come as a shock to some when reports surfaced that major economies such as Japan and Australia didn't get a chance to make a speech at the U.N. Climate Summit held in New York on Monday, allegedly due to their continued support for coal as U.N. Secretary-General Antonio Guterres pushed countries to pledge even loftier climate goals than they did under the Paris agreement.

In spite of heightened calls for phasing out coal, global coal consumption rose nearly 1 percent in 2018, according to the International Energy Agency, due to robust demand for power generation in China and India.

In post-Fukushima Japan, the government has sought to achieve a balanced energy mix and considers coal one of its main energy sources due to its advantage of being cheap, stable and safe from geopolitical risk, as it imports almost all of its oil from the Middle East.