Interesting thing going on -
I'm sure you all have heard the term 'buggy whip industry.' It usually designates a business in decline that should not be entered, because the future for it is so dim. Like horsewhips when cars were starting to appear in mass numbers.
Turns out the energy companies thought oil and coal were buggy whip industries, and stopped investing in them. Which has brought us to this point...not enough crude production, not enough coal mining, not enough gasoline refining. The invisible hand failed.
The irony, of course, is that buggy whip industries can be very profitable, because demand doesn't go to zero, competitors exit the field or reduce their commitment to it.
Like horsewhip companies in the dawn of the car....energy companies are still raking it in.
WSJ:
Meanwhile, investment in (coal) mining has dwindled in the midst of expectations that coal would keep losing market share to renewable sources, such as wind farms, and cleaner-burning natural gas. That has left inventories low.