COST-BENEFIT ANALYSIS

In a cost-benefit analysis (CBA), the cost of a remedial measure is weighed against the environmental benefits it creates. Is it worth investing in a new scrubber for a plant if the impacts on its surroundings decrease by 10%?

CBA relies heavily on the costs of environmental impacts. Some impacts may be easily expressed in monetary values, like crop loss or even increased morbidity among people. Others, like impact on biodiversity and the deple­tion of natural resources, are more difficult to describe in terms of monetary values. Large time scales and global impacts also complicate the methodology and confuse the understanding of the results. Some of the environmental con­sequences of today’s activities appear only after several hundred or thousand years. Even low interest rates tend to diminish these types of impact, even if they are very large.

A typical CBA involves a description of the expected decrease in emissions and a model of the impact pathways, such as an estimation of the average damage per emission unit. It involves a valuation of damage units such as “loss of 1 kg crop,” “one person admission to hospital due to respiratory in­fections,” etc. As an example, a part of a result table from a study in determin­ing external environmental costs for the production of electricity from coal1 is shown in Table 15.5.

The CBA technique is frequently used in the United States. It is relevant for evaluating industrial ventilation projects, but is possibly not feasible for

West Burton and Lauffen are two plant locations.

Range means the range for which impact has been estimated.

Confidence levels are high (H) If the impacts are quantified within an order of magnitude, medium (M) for order of magnitude level, and low (L) for other cases.

IQ means impacts ate quantified but not valued, and NQ means that they are not quantified but discussed.

Single projects unless software is used. The United States has produced this type of software.

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