- The discovery of new forms of energy e.g. natural gas
- The increasing use of nuclear power. This is a very powerful form of energy produced by the splitting if the nuclei of atoms.
- Increasing use of crude oil as a form of energy.
- The rising costs of mining in the deeper seams
- Exhaustion of the easily worked exposed mines.
- Improvement of technology which required less coal to be burnt especially in the iron and steel industry
- A large number of miners have had to leave the industry for better paying jobs in the industrial sector.
- Closing of some mines.
