Energy analysis of open-pit coal mining

Conclusions

1. The use of energy criteria to establish the mine boundaries corresponds to the role of coal-mining enterprises as subsystems within the energy-production system. The criteria here proposed reflect the level of technology not only within coal mining but also within the power industry and in transportation. It is important that the parameters included in the criteria have a physical basis reflecting the energy needs of the technologies employed and hence may be more reliably measured than can economic parameters. However, this is not an adequate basis for the absolute adoption of an energy approach rather than an economic approach.

2. The criteria proposed for determining the mine boundaries are based on the energy parameters both of the technologies employed and of the coal deposit, which allows the geological and other mine conditions, the processes of coal extraction and enrichment, and also transportation and energy production to be combined within a single system. This permits more reliable prediction of the determining factors, since they are based on physical parameters, which is not true of economic factors. The importance of this is evident in that, with rare exceptions, the mine boundaries may be established in the long term: 20–50 years or more.

3. There is one disadvantage in using energy analysis to solve problems associated with coal extraction: it is not traditional (although this approach — known as the exergetic approach — is widely used in other fields). However, since it is of growing importance to make rational use of nonrenewable energy resources, this disadvantage may be turned into an advantage.