Thermo-ecological cost of hard coal with inclusion of the whole life cycle chain

• Application of system exergy analysis for coal mine.
• Application life cycle assessment to the thermo-ecological cost.
• Full life cycle comparison of coal mine with and without the methane leakage.
• Thermo-ecological cost with inclusion the final type of coal user.

Fossil fuels are still the dominant source of energy in most economic sectors worldwide, particularly in the electric power sector. The transformation and usage of primary energy are connected with various unfavorable environmental effects. Mainly they are as follows depletion of constrained resources of non-renewable energy, emission of harmful wastes to the environment, emission of GHG (greenhouse gasses). To investigate these effects variety of methods have been developed, the LCA (Life-Cycle Assessment) is one of them. It has emerged as a valuable decision-support tool for both policy makers and industry in assessing the cradle-to-grave impacts of a product or process. Despite many advantages of LCA, it is unfortunately characterized by the lack of inclusion of thermodynamics law, especially second law, which is the basic physical law deciding on the resource economy in any production process. In the paper, the LCA methodology together with TEC (Thermo-Ecological Cost) is proposed to apply for exergo-ecological evaluation of fossil fuels. TEC expresses the cumulative consumption of non-renewable exergy connected with the fabrication of any useful product with additional inclusion of the consumption resulting from the necessity of compensation for environmental losses caused by the removal of harmful substances to the environment. The calculations of TEC of coal are based on the material balances of the whole chain of the production process from mine to the end-user. Within the chain in the coal mine the following sub-processes have been distinguished: preparation of the coal deposit layer for exploitation, exploitation of coal deposits, mechanical processing and enrichment of coal, ventilation of coal mine, transport, energy management of coal mines, compressed air management in coal mines and utilization of methane released during mine exploitation. Besides the processes in the mine, the end use is investigated. For this reason, the different types of coal are assigned for typical users. The potentially negative influence of utilization of coal with inclusion from cradle to grave assessment are examined on the basis of TEC evaluation.