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Main purpose of the thesis is to create proposal of the photovoltaic hybrid system for commercial building in accordance with applicable rules for energy savings program. The introductory part of the thesis describes the rules regarding the photovoltaic system parts. The next part of the thesis describes the available technical solution for realization of the photovoltaic system design and the possibilities of electric energy accumulation in these systems and how to deal with power overflows using the power flow controller and what is the negative impacts on the distribution network when switching the connected load. In the next part the design of the PV system is carried out according to the valid assumptions described in the theoretical part of the thesis. Verification of power flow controller and measurement results in UEEN laboratories. The last part of the thesis is an evaluation of the economic part of the proposed system.

Current regulations specify the minimum number of operators required per nuclear power plant. However, these requirements are based on the operation of large nuclear power plants, which are not inherent safe and can result in a meltdown. For newly developed small nuclear reactors, the current number of operators seems to be excessive causing the technology to be less competitive. Before the number of required operators can be optimised, it should be demonstrated that human errors will not endanger or cause risk to the plant or public. For this study, a small pebble bed High Temperature Reactor (HTR) Nuclear Power Plant (NPP), the Th-100, was evaluated. The inherent safety features of this type of nuclear reactor include independent barriers for fission product capture and passive heat dissipation during a loss of coolant. The control and instrumentation architecture include two independent protection systems. The Control and Limitation System is the first protection system to react if the reactor parameters exceed those of the normal operational safe zone. If the Control and Limitation System fail to maintain the reactor within the safe zone, the Reactor Protection System would at that time operate and force the reactor to a safe state. Both these automated protection systems are installed in a control room local to the reactor building, protected from adverse conditions. In addition, it is connected to a semi-remote control room, anticipated as a multi-unit control room to include the monitoring and control of the auxiliary systems. Probable case studies of human error associated with multi-unit control rooms were evaluated against the logic of the Control and Limitation System. Fault Tree Analysis was used to investigate all possible failures. The evaluation determined the reliability of the Control and Limitation System and highlighted areas which design engineers should take into account if a higher reliability is required. The scenario was expanded, applying the same methods, to include the large release of fission products in order to verify the reliability calculations. The probability of a large release of fission products compared with studies done on other nuclear installations revealed to be much less for the evaluated HTR as was expected. As the study has proved that human error cannot have a negative influence on the safety of the reactor, it can be concluded that the first step has been met which is required, when applying for a waiver to utilise a multi-unit control room for the small pebble bed HTR NPP. Also, from the study, it is recommended that a practical approach be applied for the evaluation of operator duties on a live plant, to optimise the number of operators required. This in turn will position the inherent safe HTR competitively over other power stations. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2015

Current regulations specify the minimum number of operators required per nuclear power plant. However, these requirements are based on the operation of large nuclear power plants, which are not inherent safe and can result in a meltdown. For newly developed small nuclear reactors, the current number of operators seems to be excessive causing the technology to be less competitive. Before the number of required operators can be optimised, it should be demonstrated that human errors will not endanger or cause risk to the plant or public. For this study, a small pebble bed High Temperature Reactor (HTR) Nuclear Power Plant (NPP), the Th-100, was evaluated. The inherent safety features of this type of nuclear reactor include independent barriers for fission product capture and passive heat dissipation during a loss of coolant. The control and instrumentation architecture include two independent protection systems. The Control and Limitation System is the first protection system to react if the reactor parameters exceed those of the normal operational safe zone. If the Control and Limitation System fail to maintain the reactor within the safe zone, the Reactor Protection System would at that time operate and force the reactor to a safe state. Both these automated protection systems are installed in a control room local to the reactor building, protected from adverse conditions. In addition, it is connected to a semi-remote control room, anticipated as a multi-unit control room to include the monitoring and control of the auxiliary systems. Probable case studies of human error associated with multi-unit control rooms were evaluated against the logic of the Control and Limitation System. Fault Tree Analysis was used to investigate all possible failures. The evaluation determined the reliability of the Control and Limitation System and highlighted areas which design engineers should take into account if a higher reliability is required. The scenario was expanded, applying the same methods, to include the large release of fission products in order to verify the reliability calculations. The probability of a large release of fission products compared with studies done on other nuclear installations revealed to be much less for the evaluated HTR as was expected. As the study has proved that human error cannot have a negative influence on the safety of the reactor, it can be concluded that the first step has been met which is required, when applying for a waiver to utilise a multi-unit control room for the small pebble bed HTR NPP. Also, from the study, it is recommended that a practical approach be applied for the evaluation of operator duties on a live plant, to optimise the number of operators required. This in turn will position the inherent safe HTR competitively over other power stations. / MIng (Nuclear Engineering), North-West University, Potchefstroom Campus, 2015

Thesis (PhD (Mechanical and Mechatronic Engineering))--Stellenbosch University, 2008. / ENGLISH ABSTRACT: The power conversion unit of a large solar chimney power plant converts the fluid power, first into mechanical power, and then into electrical power. In this dissertation a tool is developed to determine the layout and the number of turbines of the solar chimney power conversion unit providing the lowest cost of electricity. First, the history of the solar chimney concept and the related fields of research are presented. Potential features and configurations of the power conversion unit are introduced, and it is shown how the solar chimney power conversion unit compares to those of other applications. An outline of the dissertation is given, and its potential impact is discussed. An analytical turbine model is developed. Several modelling approaches and the performance of single rotor and counter rotating turbine layouts are compared. Preliminary turbine designs are investigated, experimentally and numerically. The main aim of the experimental investigation is to verify the applicability of the loss model used in the analytical turbine model. The aim of the numerical investigation is to evaluate a commercial software package as a tool in context with solar chimney turbines. For each component of the power conversion unit an analytical performance model is introduced. Using these models, the single vertical axis, multiple vertical axis and multiple horizontal axis turbine configurations are compared from an efficiency and energy yield point of view, and the impact of the various losses on the overall performance is highlighted. A detailed cost model for the power conversion unit is also presented. To optimize for cost of electricity this cost model is then linked to the performance models, and the resulting optimization scheme is applied to several plant configurations. It is shown that for a large solar chimney power plant the power conversion unit providing minimal cost of electricity consists of multiple horizontal axis turbines using a single rotor layout including inlet guide vanes. / AFRIKAANSE OPSOMMING: Die drywingsomsettingseenheid van ’n groot sonskoorsteenaanleg sit die vloeidrywing om, eers in meganiese drywing en dan in elektriese drywing. In hierdie proefskrif word ’n gereedskapstuk ontwikkel om die uitleg en aantal turbines van die sonskoorsteen-drywingsomsettingseenheid te bepaal wat die laagste koste van elektrisiteit lewer. Eerstens word die geskiedenis van die sonskoorsteen en verwante navorsingsvelde behandel. Moontlike eienskappe en konfigurasies vir die drywingsomsettingseenheid word voorgestel, en daar word aangetoon hoe die sonskoorsteendrywingsomsettings- eenheid vergelyk met ander toepassings. ’n Raamwerk van die proefskrif word gegee, en die potensiële trefkrag daarvan word bespreek. ’n Analitiese turbine-model word ontwikkel. Verskeie nabootsingsbenaderings en die vertoning van ’n enkelrotor en teenroterende turbine-uitlegte word vergelyk. Voorlopige turbine-ontwerpe word ondersoek, eksperimenteel en numeries. Die hoofdoel van die eksperimentele ondersoek is om die toepaslikheid van die verliesmodel in die analitiese turbine-model te bevestig. Die doel van die numeriese ondersoek is om kommersiële sagteware op te weeg as ’n gereedskapstuk in die konteks van sonskoorsteenturbines. Vir elke onderdeel van die drywingsomsettingseenheid word ’n analitiese model voorgestel. Met gebruik van hierdie modelle word die enkele vertikale-as, die veelvoudige vertikale-as an die veelvoudige horisontale-as turbinekonfigurasies vergelyk vanuit ’n benuttingsgraad- en energie-opbrengsoogpunt,en die uitwerking van die verskillende verliese op die algehele gedrag word uitgewys. ’n Kostemodel in besonderhede word vir die drywingsomsettingseenheid aangebied. Om vir die koste van elektrisiteit te optimeer word hierdie kostemodel dan gekoppel aan die vertoningsmodelle, en die gevolglike optimeringskema word toegepas op verskeie aanlegkonfigurasies. Daar word aangetoon dat vir ’n groot sonskoorsteenaanleg die drywingsomsettingseenheid wat die minimumkoste van elektrisiteit gee, bestaan uit veelvoudige horisontale-as turbines met enkelrotoruitleg en inlaatleilemme. / Centre for Renewable and Sustainable Energy Studies

The Texas ERCOT market is one of the most open, deregulated electricity markets in the world. This open market brought electricity costs down for Texas residents and businesses, creating a much more competitive economic climate. However, these low prices currently generate insufficient revenue for generators to finance construction of new or replacement generation assets. In the instance of combined cycle advanced natural gas, the Independent Market Monitor 2012 annual report estimated that a plant needed to generate 2.5 times as much as revenue it did in 2012 to incent new generation. This author argues that while the gap is still significant, the continuous changes to the ERCOT market since its inception make an historical examination like that used by the IMM less accurate. New market rules such as price caps or changes in fuel markets through new technologies like hydraulic fracturing create a very different valuation gap than a model based on historical activity alone. This analysis attempts to get a more accurate approximation of the gap through the use of publicly traded futures contracts for natural gas and electricity. Electricity futures reflect market expectations of revenue based on current and future market rules. Gas futures reflect price expectations in light of market changes like fracturing, potential LNG exports, and other changes. Financial positions can be maintained in both markets to give a fixed rate of return. Using this method, one can create a very conservative valuation model that still more accurately reflects market sentiment. This thesis starts with a brief history of ERCOT deregulation from the early 2000s to present in order to clarify for the reader the changes that have taken place in the market. It then demonstrates the futures-valuation model using an advanced combined cycle power plant as an example. / text

本文共乙冊，約八萬言，分為五章十節。 第壹章 緒論。首先闡釋本文題目之意義；其次陳述本文之研究動機、目的方法與限 制；最後說明本文研究之架構。 第貳章 假設分析的運作背景。從組織環境與組織問題的分析中，以瞭解運用假設分 析方法之緣由。 第參章 假設分析的運作。首先論述假設分析運作的理論基礎；其次解析其運作之程 序與方法。 第肆章 假設分析的應用。首先說明政策論證的內涵，模式及其與假設分析方法之關 係；其次試圖運用本文所論述之理論與方法，以檢視和評析台灣電力公司興建核能四 廠一案的政策過程。 第伍章 結論。發表本文研究之心得並提出假設分析方法成功運作的要件。

本文共壹冊，分柒章，約四萬言，章節目錄如下： 第一章：導論 一、前言，二、研究動機，三、研究目的，四、研究架構，五、研究限制。 第二章：緊急事故本質探討 一、名詞解釋，二、緊急事故性質，三、緊急事故影響與後果，四、面臨緊急事故時 之個人與組織行為，五、災變之防治。 第三章：緊急事故的管理 一、管理架構，二、管理之規劃與控制活動。 第四章：決策支援系統理論基礎 一、決策支援系統定義與特性，二、傳統EDP,MIS 與DSS 之比較，三、系統建立方法 。 第五章：緊急事故管理之決策支援系統設計 一、緊急事故下之決策程序，二、決策特徵，三、功能架構，四、系統建立。 第六章：個案實例 一、個案背景介紹，二、核能電廠緊急應變措施，三、系統需求，四、建立與實施。 第七章：結論與建議 一、結論，二、建議。 環繞人類四周環境中，常有許多不確定的災變隨時可能降臨。且發生災變時，如果資 訊缺乏或運用不當，常造成不必要的損失與傷亡。本研究係研究有關決策支援系統在 緊急事故管理上之應用，籍資訊的提供與利用，以支援緊急事故防治。 決策支援系統具有（一）易於使用，（二）模式庫與資料庫整合，（三）適於解決非 結構性問題，（四）具有良好彈性等特性，而緊急事故管理更明顯涉及決策者的價值 判斷，及對不確定環境的偏好，因此面臨這種結構程度低的問題，一個考慮完整的決 策支援系統將能提供管理人員更有效的支援。 本文之研究共分四部份，第一部份探討緊急事故的特性與本質，及面臨災變時人與群 體的行為與反應，第二部份探討緊急事故管理之決策程序與決策特性，第三部份則以 文獻分析方式探討決策支援系統相關文獻，以作為建造系統時指引，第四部份則以個 案研究法，針對核能電廠緊急事故之疏散掩蔽決策，提出應建立之決策支援系統。

This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.

Renewable energy resources in the Czech Republic, especially photovoltaics, have experienced a great boom in the past few years. The investment in the photovoltaic plants has been and will be a very promising field for investors unless too many legislative barriers are adopted to make the investments unattractive. This diploma thesis therefore elaborates a real world business case of a solar power plant. Within the business case a sensitivity analysis is being made to evaluate the influences of external factors that may have a major impract on the effectiveness and returnability of the project. Conclusions made in the analysis help to make the desicion whether to realize or not to realize the project.