If you want even higher energy costs, re-open British mines.
The first British mine to be detonated was at Hill 60 on 10 April 1915.
On several occasions, German tunnellers were within yards of large British mine "chambers."
There we saw a German command car that had run into a British mine.
On 13 October 1939, U-40 was sunk by a British mine.
The first British mine was detonated at Hill 60 on 17 February 1915.
Then on September 17, 1917, U-88 struck a British mine and sank with all hands.
The field they were in had British as well as German mines sown all over the place.
British mines operate at far greater depth than in America.
Coal output from British mines peaked in 1914, and there were a correspondingly large number of accidents around this time.