Design of future distribution grids

Dissertação para obtenção do Grau de Mestre em Engenharia Electrotécnica e de Computadores

O papel dos Sistemas de Informação Geográfica no planeamento, projecto e manutenção da Rede de Distribuição de Energia Eléctrica

Este relatório de estágio representa o desenvolvimento de uma metodologia, com recurso a Tecnologias de Informação Geográfica, que permite a identificação de zonas que condicionam os processos de planeamento, projecto e manutenção das estruturas que compõem a Rede de Distribuição de Energia Eléctrica. Centra-se assim nas Tecnologias de Informação Geográfica enquanto instrumentos que permitem realizar estudos de carácter territorial com relevância para o sector energético. São trabalhadas a identificação e delimitação de zonas de gelo, zonas de poluição industrial e zonas de salinidade em Portugal Continental. A delimitação destas zonas foi realizada com recurso a ferramentas de análise espacial, utilizando dados fidedignos provenientes de Instituições da Administração Pública. São documentadas também tarefas extraordinárias propostas pela EDP Distribuição - Energia, S.A. Desta forma é possível compreender as vantagens e desvantagens da utilização destas tecnologias por parte da EDP Distribuição, de forma a melhorar a gestão dos recursos disponíveis, para ajudar a manter a qualidade do serviço prestado. Ficou no entanto a recomendação de uma maior aposta nestas tecnologias.

Renewable Power Sources

Of all of the sources of renewable energies available one can argue that the most abundant and accessible are solar power, radiation, and the energy of the tides (70 % of the earth surface is covered by water). The tidal wave energy hasn’t seen a widespread distribution yet, mainly due to the lack of interest of the governments, most of the coastal areas of the world are exclusive responsibility of the governments, thus not easily open for private venture. Considering solar power, there exist two main fields of application, land based systems and space based systems. The former systems are still in a very embryonic phase, with Japan being the lead researcher in the field, with an experimental satellite-power station to be launched before 2010. Land based systems, on the other hand, are well studied, with major research and application programs in all known forms of solar power production. Given a minimum value of incident radiation, and applying the appropriate system, (i.e. power plant type), for any given area the solar power becomes an income-producing industry.

Is Information Power? Using Mobile Phones and Free Newspapers during an Election in Mozambique*

African elections often reveal low levels of political accountability. We assess different forms of voter education during an election in Mozambique. Three interventions providing information to voters and calling for their electoral participation were randomized; an SMS-based information campaign, an SMS hotline for electoral misconduct, and the distribution of a free newspaper. To measure impact, we look at official electoral results, reports by electoral observers, behavioral and survey data. We find positive effects of all treatments on voter turnout. We observe that the distribution of the newspaper led to more accountability-based participation and to a decrease in electoral problems.

Control in distribution networks with demand side management

The way in which electricity networks operate is going through a period of significant change. Renewable generation technologies are having a growing presence and increasing penetrations of generation that are being connected at distribution level. Unfortunately, a renewable energy source is most of the time intermittent and needs to be forecasted. Current trends in Smart grids foresee the accommodation of a variety of distributed generation sources including intermittent renewable sources. It is also expected that smart grids will include demand management resources, widespread communications and control technologies required to use demand response are needed to help the maintenance in supply-demand balance in electricity systems. Consequently, smart household appliances with controllable loads will be likely a common presence in our homes. Thus, new control techniques are requested to manage the loads and achieve all the potential energy present in intermittent energy sources. This thesis is focused on the development of a demand side management control method in a distributed network, aiming the creation of greater flexibility in demand and better ease the integration of renewable technologies. In particular, this work presents a novel multi-agent model-based predictive control method to manage distributed energy systems from the demand side, in presence of limited energy sources with fluctuating output and with energy storage in house-hold or car batteries. Specifically, here is presented a solution for thermal comfort which manages a limited shared energy resource via a demand side management perspective, using an integrated approach which also involves a power price auction and an appliance loads allocation scheme. The control is applied individually to a set of Thermal Control Areas, demand units, where the objective is to minimize the energy usage and not exceed the limited and shared energy resource, while simultaneously indoor temperatures are maintained within a comfort frame. Thermal Control Areas are overall thermodynamically connected in the distributed environment and also coupled by energy related constraints. The energy split is performed based on a fixed sequential order established from a previous completed auction wherein the bids are made by each Thermal Control Area, acting as demand side management agents, based on the daily energy price. The developed solutions are explained with algorithms and are applied to different scenarios, being the results explanatory of the benefits of the proposed approaches.