Transmission charges are levied against generators and suppliers for their use of transmission networks. The majority of existing transmission charging methods were designed for a system dominated by conventional and controllable generation. The resultant transmission charges reflect network users’ contribution to the system peak. The integration of renewable generation brings fundamental challenges in transmission planning and charging. Main criteria of transmission planning have changed from meeting system peak demand to the trade-offs between operational and investment costs. Transmission charging is required to effectively reflect these trade-offs. This research work aims to develop novel transmission charging methods for low carbon power systems, reflecting the contribution to transmission investments from different generation technologies, different locations, and critically different times. It firstly identifies the key drivers and key conditions of transmission investments under the economic criteria. In the second step, the key drivers and conditions are reflected in the developing of T-LRIC method, ToU-LRIC method and ToU-ICRP method. Major innovations of the proposed methods include 1. reflecting the trade-offs between operational and investments costs by employing investment time horizons to reflect the impacts of system operation on transmission investments (T-LRIC method and ToU-LRIC method). 2. differentiating various generation technologies by firstly quantifying their impacts on the time horizons of network investments, then translating these impacts to transmission charges (T-LRIC method and ToU-LRIC method). 3. providing time-specific transmission charges, in which Time-of-Use periods are identified by clustering time-series congestion costs or transmission charges, thus reflecting the typical conditions of system congestions and the required transmission investments (ToU-LRIC method and ToU-ICRP method). The main benefits from introducing these innovations are i) to guide the short-run behaviours of network users, thus mitigating transmission congestions and promoting efficient utilization of existing networks; ii) to incentivize appropriate generation expansion, thus reducing or deferring costly future transmission investments.

Orientador: Dionízio Paschoareli Júnior / Resumo: Diante das constantes mudanças nas regulamentações do setor elétrico, há necessidade de se realizar análises de impactos dessas regulamentações nos setores envolvidos, como consumidores e distribuidoras de energia elétrica.O Brasil tem aprimorado constantemente as regulamentações do setor de geração distribuída. As melhorias feitas partem de pesquisas realizadas em universidades, projetos de Pesquisa e Desenvolvimento, e consultas públicas. Além dessa inovação no setor residencial, a Agência Nacional de Energia Elétrica (ANEEL) regulamentou uma nova modalidade tarifária, a tarifa branca, que é uma tarifa horária (Time-of-Use), com3 postos horários diferentes ao longo do dia, cada um com um valor de tarifa, com o objetivo de incentivar o deslocamento da carga dos horários mais sobrecarregados do sistema elétrico para horários ociosos. Esta regulamentação entrará em vigor a partir de janeiro de 2018 e por ser uma modalidade diferente da que os consumidores estão acostumados, há a necessidade de verificar os impactos deste tipo de tarifa no consumidor residencial considerando seus hábitos de consumo atuais e verificando a influência desta tarifa nos consumidores que estiverem dispostos a mudar seus hábitos de consumo. A proposta desta tese é apresentar os impactos desta nova modalidade tarifária em consumidores residenciais com microgeração fotovoltaica, considerando situações com consumo atual e com deslocamento de carga, através do desenvolvimento de uma metodologiacapaz de re... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In the face of constant changes in the regulations of the electricity sector, there is a need to analyse the impacts of these regulations on the sectors involved, such as electricity consumers and distributors. Brazil has presented a constant growth of photovoltaic microgeneration installations in residential consumers connected to the electric grid and has constantly improved the regulations of the distributed generation sector. The improvements made in these regulations are based on research carried out in universities, Research and Development projects, and public consultations. In addition to this innovation in the residential sector, the National Electric Energy Agency has regulated a new tariff modality, the white tariff, which is a Time-of-Use tariff, with 3 different timetables throughout the day, each with a with the objective of encouraging the shift of the load from the overloaded hours of the electrical system to idle schedules. This regulation will come into effect from January 2018 and since it is a different modality from which consumers are accustomed, there is a need to verify the impacts of this type of tariff on the residential consumer considering their current consumption habits and verifying the influence of this tariff consumers who are willing to change their consumption habits. The purpose of this thesis is to present the impacts of this new tariff modality on residential consumers with photovoltaic microgeneration, considering situations with current... (Complete abstract click electronic access below) / Doutor

In South Africa, where 75% of the worlds platinum is produced, electricity tariffs have increased significantly over recent years. This introduces challenges to the energy intensive mineral processing industry. Within the mineral processing chain, run-of-mine ore milling circuits are the most energy-intensive unit processes. Opportunities to reduce the operating costs associated with power consumption through process control are explored in this work. In order to reduce operating costs, demand side management was implemented on a milling circuit using load shifting. Time-of-use tariffs were exploited by shifting power consumption of the milling circuit from more expensive to cheaper tariff periods in order to reduce overall costs associated with electricity consumption. Reduced throughput during high tariff periods was recovered during low tariff periods in order to maintain milling circuit throughput over a week long horizon. In order to implement and evaluate demand side management through process control, a load shifting controller was developed for the non-linear Hulbert model. Implementation of the load shifting controller was achieved through a multi-layered control approach. A regulatory linear MPC controller was developed to address technical control requirements such as milling circuit stability. A supervisory real-time optimizer was developed to meet economic control requirements such as reducing electricity costs while maintaining throughput. Scenarios, designed to evaluate the sensitivities of the load shifting controller, showed interesting results. Mill power set-point optimization was found to be proportionally related to the mineral price. Set-points were not sensitive to absolute electricity costs but rather to the relationships between peak, standard, and off-peak electricity costs. The load shifting controller was most effective at controlling the milling circuit where weekly throughput was between approximately 90% and 100% of the maximum throughput capacity. From an economic point of view, it is shown that for milling circuits that are not throughput constrained, load shifting can reduce operating costs associated with electricity consumption. Simulations performed indicate that realizable cost savings are between R16.51 and R20.78 per gram of unrefined platinum processed by the milling circuit. This amounts to a potential annual cost saving of up to R1.89 m for a milling circuit that processes 90 t/h at a head grade of 3 g/t. / Dissertation (MEng)--University of Pretoria, 2015. / Electrical, Electronic and Computer Engineering / Unrestricted