On the Selection of Methods and Tools for Analysis of Heat and Power Plants

Sammanfattning: The business climate of the energy market has been eventful over the last two decades, particularly with the introduction of the deregulated electricity market and promotion of environmental issues. This has subsequently lead to new analysis criteria, influencing both technology requirements and production costs. To be able to manage all the questions that have arisen from this the knowledge of the available analysis methods and tools has become crucial. In this thesis eight different methods and tools have been investigated to provide the reader with an understanding of what information they provide, both separate and in combination, and for which decision-making situations they could be suitable. These methods and tools have been applied on a number of case studies presented in the attached papers to illuminate their advantages and limitations. When analyses of heat and power plants are carried out the focus of attention is often the operation of the plant. This is probably due to the fact that it is this part of the lifetime of the plant which is profitable, as well as the period of the lifetime when the plant is visible for the owner. However, with the introduction of environmental management systems and more decisive governmental economic incentives directing the choice of plant configurations and use of fuel, it is perhaps not sufficient to only consider this phase of the total lifetime. To be able to make an investment with as low a risk as possible, the lifecycle perspective has to be considered, bringing forward not only the lifecycle cost, but also the lifecycle environmental impact. Today there is no 'universal', all-embracing method or tool that results in an analysis that takes technical, economic and environmental conditions into consideration. However, the available arsenal of methods and tools for analysis cover these aspects between them. In this thesis an evaluation deck, where the different methods and tools can be combined, is proposed in order to include the lifetime aspects that any heat and power plant involves. It is shown in this thesis that heat and power plants that have high efficiency and therefore are considered as environmentally-friendly during operation, do not necessarily have this feature over the entire lifecycle. It is further shown that combinations of methods and tools introduce vital information and could advantageously be combined for more reliable results.