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The use of renewable energy and specifically solar energy in power systems is rapidly increasing due to significantly lower carbon emissions and low energy costs. Although the widespread use of renewable energy generation provides many benefits to the power system, high levels of renewable energy generation introduce several new challenges to the power system operation. The high level of uncertainty associated with solar power output complicates operation and planning decisions for the power system. Therefore, accurate and reliable solar power forecasts are needed for the planning and operation of the power system more than ever before. This thesis first focuses on improving probabilistic solar power forecasts that provide detailed information on the uncertainty of the forecasts. The proposed copula-based Bayesian method utilizes the underlying relation between temperature and solar power output to improve forecast accuracy and performance. The results show significant improvement compared to the direct use of temperature as an input to the forecast model. Secondly, a novel improvement is made to the State Frequency Memory (SFM) method for solar forecasting. The SFM model, which is based on the Long Short Term Memory (LSTM) method, incorporates the patterns in the frequency domain on top of the time domain considerations. The SFM model is improved by frequency band selection based on the Fourier transform of the solar power data. The improved SFM model is able to include the low-frequency patterns in solar data compared to the sampling frequency of second and minute-level and significantly improve results in very short-term forecasting. Thirdly, One of the challenges that arise from high penetration of solar power is investigated further. An essential part of power system operation is maintaining the balance between generation and loads in the power system. The intermittency of solar power makes it very challenging for the operators to maintain the balance and increases the need for spinning reserves in the power system. In this thesis, solar forecasts are used in a multistep optimization model to control energy storage and electric vehicle charging to minimize violations from the ramp rate limits of the system. A detailed analysis of forecast error is performed to tackle the trade-off between longer forecast horizons and increasing forecast error and find the optimal forecast horizon for predictive solar power smoothing.

This thesis is a study of architectural form in relation to energy. Energy performance is rooted in form. Overall performance in the practice of architecture includes necessarily consumption as a form constraint. The term energy in this body of work relates to the social circumstance that the current state of the environment imposes on all facets of life, including how our buildings contribute to the anthropogenic warming of the earth's atmosphere. Humans are consumptive and so our buildings, a product of our work, are inherently consumptive as well. The challenge is to design environments that stimulate responsible actions by considering energy consumption throughout the design process. This thesis proposes that an architecture which responds with significance explores the energy-in-form to make a contribution to the current condition in which we live. On an abstract level, formal elements of negation and the condition of boundary are explored in relation to energy. On a more factual level, the impact of energy on site orientation, shading, and in-between zones are tested. Form in the study of the proportions of the Maison Carrée is expressed in the process of making concrete objects and the regulating geometry and formal conditions of the final Cornerstore building design. / Master of Architecture

With the growing concerns of climate change due to fossil fuel-based electricity generation, solar integration to the grid is swiftly increasing. However, the intermittency of solar power is a major obstacle to harness it efficiently. Energy storage system (ESS) with its declining price over the last few years is a viable solution to address this issue. Another source of greenhouse gas emission is fossil fuel-based transportation system which is likely to be replaced by electric vehicles (EVs) in near future. To match the driving range of EVs with the internal combustion engine-based vehicle, fast and extreme fast charging infrastructure in terms of power electronics and control must be developed. Utilization of multiport converters in both applications (EV charging and grid-connected solar+ESS) ensures higher efficiency, higher power density and improved reliability owing to the reduced number of power stages. This dissertation discusses multiport converter design and its control method for photovoltaic (PV) and EV applications. A system-level model predictive control (MPC) for a grid-connected ESS system with PV and load is developed to smooth the PV intermittency and improve ESS lifetime. Also, power electronic circuit level MPC guarantees real and reactive power control, output voltage regulation, and maximum power point tracking. Furthermore, a comprehensive review of converter topologies is carried out which leads to the selection of the dual active bridge (DAB) dc-dc converter as the fundamental power conversion unit. DAB topology is well-suited for its high efficiency, high power density, bidirectionality, soft switching, isolation, and wide range of voltage transfer ratio. Adding a resonant tank (LC or CLLLC) in the DAB configuration results in lower conduction loss and extended soft switching range. A three-port dc-dc-dc converter based on DAB with LC & CLLLC resonant tank has been introduced that integrates EV battery, PV, and dc-link for EV fast charging.

Master of Arts / Department of Landscape Architecture/Regional and Community Planning / Claude A. Keithley / In these times of high energy costs, dwindling supplies of fossil fuels, and talk of “global warming,” we must decide what we are going to do to with the abundance of wind energy available in Kansas. We can no longer afford to “drift,” not caring about the sources of our electricity, or what we are doing to the planet. We must act now to ensure a bright future for our children. Many wind turbines are being erected across Kansas, and this natural resource of wind energy is one that should be tapped, but only after careful planning. There are many factors to consider regarding wind farms; environmental concerns, economics, impacts on the health and well-being of individuals living near wind farms, and tax implications, to mention only a few. Studies are being completed on these issues, and due consideration must be given prior to construction. There are areas across the state that should be avoided when locating wind farms, and other areas in which wind turbines might be a natural “fit.” It is the latter areas which should be the focus of attention for construction, but again, only after giving careful consideration to the overall effects. Wind energy has become a part of Kansas, but future site selections should be done only after careful planning.

Climate change has become the most important global environmental problem we face today. Agriculture, forestry and the land use sector not only contribute to national economies but also provide a source of greenhouse gas (GHG) emissions as well as a carbon store, contributing approximately 20% but removing about 16%. Energy crops and associated increases in soil carbon sequestration from different ground covers through various land management strategies are examples of approaches that could be adopted to reduce GHG emissions. A number of these options have an associated economic cost to the land manager and it is important to understand what is economically and socially viable by understanding the link between energy crop adoption and a range of socio-economic factors. Agent-based modelling (ABMs) has been identified as providing a promising approach to integrate social, economic and biophysical processes. In the past these areas of research have been mainly studied separately but now there is an urgent need to address these areas in a combined way. Economic rationalisation is fundamental to farmers’ decision-making, although not wholly representative and non-economic factors were identified. The estimated GHG mitigation potential of bioenergy crops at current adoption levels is modest when taking Scotland’s national GHG emissions into account, however, more significant when considering the agricultural sector in isolation. This contribution can only increase with improved management practices and policy designed to encourage adoption and improve energy security. This work will contribute to a greater understanding of bioenergy land use strategies. This project used North East Scotland as the case study, with raw data collated by questionnaire, however, conclusions drawn add to the broader understanding of the link between socio-economic activity, bioenergy adoption and GHG emissions.

The increasing share of renewable electricity will make energy storage technologies indispensable in the future. In this study, the potential of grid energy storage technologies is discussed, focusing on the Nordic countries as well as Germany. It is challenging to balance the intermittency of wind power and solar power production in the energy system. In Norway and Sweden, and to some extent Finland, hydropower is a very important balancing resource. Compressed Air Energy Storage (CAES) is a technology that has not had a real breakthrough yet. There are ongoing projects at different locations where one of the targets is to achieve better round-trip efficiency by taking care of the heat generated at compression. Pumped hydroelectric storage (PHS) has advantages in being cost-efficient and has a high round-trip efficiency. There is probably a high theoretical potential of new generating capacity in Norway and Sweden, but the electricity cost does not vary enough for new developments to be profitable at the moment. The environmental and social impact of PHS plants is an important and difficult aspect to handle. Power-to-gas, power-to-power and hydrogen storage has been getting more attention recently but needs more research to increase the round-trip efficiency and to reduce the costs of electrolysers, storage and fuel cells. Batteries can be well suited as a minute reserve or for peak shaving but are currently not cost-efficient for long-time storage. With lower prices and the possibility of using more abundant metals with less environmental and social impact batteries could play a larger role in electric grids. There might be possibilities of integrating batteries in electric vehicles with power systems as well.To speed up the development of energy storage technologies, governmental subsidies might be necessary. In the future, a larger variation in electricity cost can be expected during different times of the day and the year, which will make energy storage facilities more profitable.