摘要：Externalities and their costs are incurred when negative social and economic activities of some party have an impact on others and this impact is not offset by expenditures to liquidate it. For example, in the electric power industry, external costs are generated when electricity producers do not incur expenditures required to liquidate adverse effects of their actions that are borne by another party. When a producer bears these expenditures, they are transformed into direct costs and are thus no longer external costs. They constitute components of direct manufacturing costs in the same way as other production costs [10, p. 58].
