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Abstract

Niniejsza publikacja przedstawia metodykę DEA jako narzędzie do oceny efektywności technologii energetycznych. W pierwszej części pracy ukazano podstawowe narzędzia wykorzystywane do oceny portfela projektów inwestycyjnych w przemyśle energetycznym. W dalszej części scharakteryzowano metody Data Envelopment Analysis (DEA), czyli nieparametryczne procedury ustalania efektywności technologicznej badanych obiektów pod względem analizowanych czynników. W części praktycznej – wykorzystując analizę DEA – dokonano przykładowej oceny efektywności trzynastu technologii energetycznych, w tym technologii nadkrytycznego spalania węgla, zgazowania węgla połączonego z turbiną gazową oraz samodzielnego układu turbiny gazowej. Do analizy wykorzystano model nadefektywności nieradialnej z uwzględnieniem podziału na nakłady decyzyjne, niedecyzyjne oraz produkty pożądane i niepożądane. Dodatkowo przeprowadzona została analiza wyników dla przykładowej technologii. Zostały wytłumaczone możliwe sposoby interpretacji wyników końcowych z punktu widzenia obiektów efektywnych, jak i nieefektywnych. W tym drugim przypadku przedstawiono także kalkulację rozwiązania wzorcowego dla danej instalacji wraz z wnioskami co do skali działalności.
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Abstract

This publication presents an assessment of the economic efficiency of a hypothetical installation for the gasification of the municipal and industrial waste for the production of syngas used subsequently for the production of energy or chemical products. The first part of the work presents an example of a technological system for the energo-chemical processing of coal mud and municipal waste, based on the gasification process using a fluidized bed reactor. A hypothetical installation consists of two main blocks: a fuel preparation unit and a gasification unit. In the fuel preparation installation, reception operations take place, storage, and then grinding, mixing, drying and transporting fuel to the gasification unit. In the gasification installation, fuel gasification, oxygen production, cooling and purification of raw process gas and ash treatment are carried out. The following key assumptions regarding the gasification process, as well as the capital expenditures and operating costs related to the process, were estimated. Consequently, based on the method of discounted cash flows, the unit cost of generating energy contained in the synthesis gas (cost of energy, COE) was determined and the results were interpreted. In order to obtain an acceptable efficiency of the gasification process for waste fuels for the production of alternative fuel (process gas), it is necessary to supplement the mixture of waste coal and coal mud with the RDF. In this case, the unit cost of fuel measured by the PLN/GJ index is lower than in the case of hard coal and comparable with brown coal. The use of coal mud for the production of process gas in an economically efficient way is possible only in the case of changes in the legal system allowing for charging fees for the utilization of industrial waste – coal mud.
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Abstract

Hydrogen as a raw material finds its main use and application on the Polish market in the chemical industry. Its potential applications for the production of energy in fuel cell systems or as a fuel for automobiles are widely analyzed and commented upon ever more frequently. At present, hydrogen is produced worldwide mainly from natural gas, using the SMR technology or via the electrolysis of water. Countries with high levels of coal resources are exceptional in that respect, as there the production of hydrogen is increasingly based on gasification processes. China is such an example. There some 68% of hydrogen is generated from coal. The paper discusses the economic efficiency of hydrogen production technologies employing lignite gasification, comparing it with steam reforming of natural gas technology (SMR). In present Polish conditions, this technology seems to be the most probable alternative for natural gas substitution. For the purpose of evaluating the economic efficiency, a model has been developed, in which a sensitivity analysis has been carried out. An example of the technological process of energy-chemical processing of lignite has been presented, based on the gasification process rooted in disperse systems, characteristics of the fuel has been discussed, as well as carbon dioxide emission issues. Subsequently, the assumed methodology of economic assessment has been described in detail, together with its key assumptions. Successively, based on the method of discounted cash flows, the unit of hydrogen generation has been determined, which was followed by a detailed sensitivity analysis, taking the main risk factors connected with lignite/coal and natural gas price relations, as well as the price of carbon credits (allowances for emission of CO2) into account.
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