Brochet is a remote, off-grid community located in Northern Manitoba, Canada. The existing diesel generating system is characterized by high economic and environmental costs. As the existing diesel generators are nearing the end of their operational lifespan, this study uses the HOMER model to determine an optimum electricity system design at Brochet that has high electrical reliability, least cost, and low emissions. Three potential power generation options were considered and evaluated, namely: 1) only diesel, 2) only wind, 3) a mix of both. The wind-diesel hybrid system performed best for all the evaluation criteria. While maintaining high reliability, this hybrid system design resulted in 19 % reduction in electricity cost, and 30 % reduction of CO2 when compared to the existing electricity system at Brochet. Thus, this study concludes that the wind-diesel hybrid system is the optimum electricity system design for Brochet and proposes this system replace the existing system.

This thesis describes a research study that examined how collaborative reflective practice with three staff members in a middle years school affected their psychological constructs of what constitutes a good school. Using an action research design, the study made use of personal construct psychology and the methodology of repertory grid technique. Repertory grid results were analyzed using methods developed from personal construct theory (cluster analysis, principal components analysis and messy change grid analysis). This permitted insight into the nature and processes of changes that occurred. These processes were examined in light of Leithwood’s work on teacher development and Fullan’s thoughts on educational change. Using these models as an analytical framework, an evaluation was made of the potential uses and value of repertory grid technique in middle schools. The technique aligns well with the Leithwood and Fullan models and has notable benefits and advantages to offer the field of educational leadership.

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Different HVDC grid types and the respective protection options are discussed. An earthed bi-pole HVDC grid was modeled in PSCAD, and using simulation results, the necessity of di/dt limiting inductors to contain the rise of fault currents within the capacity of current hybrid DC breakers is demonstrated. The impact of different inductor sizes on current rise was studied. A fault detection and localization scheme using the rate of change of voltage (ROCOV) measured at the line side of the di/dt limiting inductors is proposed. The protection system was modeled and tested under different fault types and locations. The results show that the proposed method of HVDC grid protection is feasible using the current hybrid DC breaker technology. A systematic procedure for setting the necessary protection threshold values is also demonstrated.

By using IT-solutions, the flexibility on the demand side in the electrical systems could be increased. This is called demand response and is part of the larger concept called smart grids. Previous work in this area has concerned the utilization of demand response by grid owners. In this thesis the focus will instead be shifted towards the electrical companies that have balance responsibility, and how they could use demand response in order to make profits. By investigating electrical appliances in hourly measured households, the business value from decreasing electrical companies’ power imbalances has been quantified. By an iterative simulation scheme an optimal value was found to be 977 SEK/year and appliance. It could however be shown that the value became larger for energy inefficient households, and that such consumers’ participation in a demand response market would be prioritized ahead of other measures like isolating walls is rather unlikely. Thermal appliance whose load depend on the outdoor temperature are less valuable for demand response during the summer months, and the annual value would increase if less seasonally dependent appliances were used. Additionally, by increasing the market price amplitudes and the imbalance price volatility, it could be shown that the potential for such demand response markets is larger in e.g. the Netherlands and Germany.

The feasibility of wood based energy plants in the off-grid Brochet community in Manitoba were analyzed by survey, interviews and document review in this research. Four areas were explored to assess the suitability of biomass energy generation, namely: the community’s perspective, resource assessment, technology availability, and cost attractiveness. Harvesting sufficient woody biomass from local wild fire burnt areas, in particular, as well as local green forests could be an appropriate and feasible option. A heat only plant is considered to be the best choice for biomass plant establishment in Brochet, followed by combined heat and power plants. A cost analysis showed that a biomass plant at Brochet is more economical than the current planned investment in the diesel power facility. The lack of resolve about who wants to run and pay for the operation and the uncertainty of the reliability of biomass technologies are two large barriers to biomass energy generation in the community. Overall, biomass energy generation options are promising to eliminate or reduce the use of fossil fuel in Brochet.

Brochet is a remote, off-grid community located in Northern Manitoba, Canada. The existing diesel generating system is characterized by high economic and environmental costs. As the existing diesel generators are nearing the end of their operational lifespan, this study uses the HOMER model to determine an optimum electricity system design at Brochet that has high electrical reliability, least cost, and low emissions. Three potential power generation options were considered and evaluated, namely: 1) only diesel, 2) only wind, 3) a mix of both. The wind-diesel hybrid system performed best for all the evaluation criteria. While maintaining high reliability, this hybrid system design resulted in 19 % reduction in electricity cost, and 30 % reduction of CO2 when compared to the existing electricity system at Brochet. Thus, this study concludes that the wind-diesel hybrid system is the optimum electricity system design for Brochet and proposes this system replace the existing system.

The current trend in the wind power industry is to develop wind turbines of constantly increasing size and rated power, as well as wind farms of growing size and installed wind power. A careful study of the behaviour of the wind turbines during their operation is of crucial importance in the planning phase and in the design stage of a wind farm, in order to minimize the risks deriving from a non accurate prediction of their impact in the electric grid causing sensible faults of the system. To analyze the impact of the wind turbines in the system, motivates the development of accurate yet simple models. To be able to practically deal with this topics, a simple model of a wind turbine system is investigated and developed; it has the aim to describe the behaviour of a wind turbine in operation on a mechanical standpoint. The same reduced order simple model can also be employed for control system studies; the control system model that can’t be used in generation, can use the reduced model. Together with the analytical description of such model, is realized a MatLab code to numerically analyse the response of the system, and the results of the simulation through such code are presented. The objective of this thesis has been to provide a simple benchmark tool in MatLab for grid integration and control studies for interested researchers.

This thesis describes a research study that examined how collaborative reflective practice with three staff members in a middle years school affected their psychological constructs of what constitutes a good school. Using an action research design, the study made use of personal construct psychology and the methodology of repertory grid technique. Repertory grid results were analyzed using methods developed from personal construct theory (cluster analysis, principal components analysis and messy change grid analysis). This permitted insight into the nature and processes of changes that occurred. These processes were examined in light of Leithwood’s work on teacher development and Fullan’s thoughts on educational change. Using these models as an analytical framework, an evaluation was made of the potential uses and value of repertory grid technique in middle schools. The technique aligns well with the Leithwood and Fullan models and has notable benefits and advantages to offer the field of educational leadership.

Sensor network web services have recently emerged as promising tools to provide remote management, data collection and querying capabilities for sensor networks. They can be utilized in a large number of elds among which Demand-Side Energy Management (DSEM) is an important application area that has become possible with the smart electrical power grid. DSEM applications generally aim to reduce the cost and the amount of power consumption. In the traditional power grid, DSEM has not been implemented widely due to the large number of households and lack of ne-grained automation tools. However by employing intelligent devices and implementing communication infrastructure among these devices, the smart grid will renovate the existing power grid and it will enable a wide variety of DSEM applications. In this thesis, we analyze various DSEM scenarios that become available with sensor network web services. We assume a smart home with a Wireless Sensor Network (WSN) where the sensors are mounted on the appliances and they are able to run web services. The web server retrieves data from the appliances via the web services running on the sensor nodes. These data can be stored in a database after processing, where the database can be accessed by the utility, as well as the inhabitants of the smart home. We showthat our implementation is e cient in terms of running time. Moreover, the message sizes and the implementation code is quite small which makes it suitable for the memory-limited sensor nodes. Furthermore, we show the application scenarios introduced in the thesis provide energy saving for the smart home.