ABSTRACT
The use of low-grade fuels depends not only on their availability and supply security but also on the technological feasibility of procurement (mining or harvesting), transport, storage and the extent of waste generation on use, potentially to the atmosphere, water courses and land. Each stage of the fuel cycle has an environmental (or external) cost, and these costs should be internalized to the operation. They must be added to the other costs of planning, development, exploitation and use of the fuel, which are the industry or internal costs.
