Question

You have been asked to evaluate the economic implications of various methods for cooling condenser effluents from a 200-MW steamelectric plant. There are two basic types of cooling towers: wet and dry. Furthermore, heat may be removed from condenser water by (1) forcing (mechanically) air through the tower or (2) allowing heat transfer to occur by making use of natural draft. Consequently, there are four basic cooling tower designs that could be considered. Assuming that the cost of capital to the utility company is 12% per year, your job is to recommend the best alternative (i.e., the least expensive during the service life). Further, assume that each alternative is capable of satisfactorily removing waste heat from the condensers of a 200-MW power plant. What noneconomic factors can you identify that might also play a role in the decision-making process?

Answer 1

To evaluate the economic implications of cooling condenser effluents, consider the cost of each alternative over its service life. Non-economic factors such as environmental impacts should also be considered.

Step-by-step explanation:

In order to evaluate the economic implications of various methods for cooling condenser effluents from a 200-MW steam-electric plant, we need to consider the cost of each alternative over its service life. The four basic cooling tower designs that could be considered are wet towers with forced air circulation, wet towers with natural draft, dry towers with forced air circulation, and dry towers with natural draft. To determine the least expensive alternative, the cost of capital to the utility company, which is 12% per year, should be taken into account. Each alternative should be evaluated based on its initial cost as well as any operating and maintenance costs. The alternative with the lowest total cost over its service life would be the recommended choice.

However, it's important to note that in addition to economic factors, there are also non-economic factors that might play a role in the decision-making process. Some of these non-economic factors could be environmental impacts, public perception, regulatory requirements, and land availability. These factors may not have a direct monetary value but could have long-term implications for the plant's operations and reputation. Therefore, they should also be considered when making the final decision.

Answer 2

The alternative with the lowest present worth is considered the least expensive over its service life and is recommended.

Additionally, noneconomic factors that might play a role in the decision-making process include environmental impact, land use, water consumption, and local regulations. For instance, wet cooling towers may have higher water consumption but better heat rejection efficiency compared to dry cooling towers. Environmental regulations and community concerns about water usage or noise pollution from cooling towers might influence the choice of design.

Other factors could include the reliability of each cooling tower design, ease of maintenance, and the adaptability of the system to varying environmental conditions. The impact on the aesthetics of the surrounding area might also be a consideration, especially in regions with strict zoning regulations.