Thesis--Wisconsin. / Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 653-682).

Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2011. / Initiatives that are directed towards improving power management by a utility provider have to consider technical feasibility, socio-economic and the environment. Patterns of power consumption world over indicate that demand for electricity has over the years been on the rise due to increase in activities that demand usage of electricity. Such activities include construction and property development, development of industries and infrastructure. These activities have strained the power production, whose development does not match the increase in demand. ESKOM, a government authority mandated to generate, transmit and distribute power in South Africa has seen demand surpassing its generation capacity, hence resorting to load shedding actions. Load shedding imposes inconveniences to the consumers who are completely disconnected from the grid, translating to unpredictable periods of darkness. Utility providers have an option of constructing new peaker plants which lie idle most of the day, to take care of high demand during the peak periods, hence, avoid effecting load shedding actions. Various ways of managing load have been presented in this research. In particular, the research investigated possible ways utilities use in managing their capacity with an aim of developing an alternative method and tool for Demand Side Management applications that can be used by energy utility to improve reliability, manage and control consumption of electrical energy through selective shedding of the load connected to the consumer when the demand surpasses the utility's safe capacity.

published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management

As one of the main contributors to greenhouse gas emissions, the electricity sector is anticipated to go through the following transitions in order to meet deep decarbonization targets for a sustainable future: 1) on the supply side, the electric grid is increasing its reliance on renewable generation, such as wind and solar; 2) on the demand side, heating is shifting from direct burning of fuel on site to electric, namely heat pumps. This dissertation evaluates the benefits of selected methods to alleviate pressing challenges associated with the electricity sector transitions on both the supply side and the demand side. First, on the supply side, the benefits of renewable generation forecasting coupled with storage are evaluated for an electric grid with high wind energy penetration and load following generation served by fossil fuels. A time series based forecasting method is found to have high forecasting accuracy and low computational costs. This methodology is applied to a real world situation in Sao Vicente, an island with 30% current wind energy penetration. The simulation results show that coupling forecasting and energy storage would further increase the wind penetration up to 38% without additional installation of wind turbines. Second, on the demand side, the benefits of demand side management using heat pumps enabled by the inherent thermal storage of the building envelope are evaluated during extreme cold events when the electric demand peaks and the wind power is often highly fluctuating. A second order thermal model is developed to thoroughly characterize the thermal inertia and leakage of the building envelope and quantify the amount of flexibility the building envelope is able to provide. This methodology is applied to five historical extreme cold events in New York City and the simulation results show that the requirements for short term ramping due to high wind variability are greatly reduced through the sequential controls of the heat pumps. This dissertation also studies the implications of the electricity sector transitions on the residential sector with regard to costs, energy, missions, and policy. Four representative residential city blocks located in three different climate regions of the United States are analyzed using fine spatial and temporal real historical consumption and weather data. Residential blocks in different climate regions have different weather patterns, demand profiles, and local renewable resources. Future energy scenarios with electric heating at high renewable penetration levels are modeled and compared for the representative residential city blocks. Detailed costs comparisons are evaluated for various technological interventions including 1) air source and ground source heat pumps; 2) battery and thermal storage; and 3) wind and solar generation. This dissertation finds that 1) the optimal wind and solar generation mix varies with location and amount of storage and 2) battery storage is more cost effective than thermal storage, ground source heat pumps, and overbuilt renewable generation. In addition, optimal pathways to deep decarbonization for these representative residential city blocks are proposed and compared. Strategic actions are identified for the homes and suggestions are discussed for policy makers and local utilities. This dissertation through its methodologies and analysis enables home owners and policy makers to make cost assessments in achieving the goals of deep decarbonization.

Energy efficiency stands out with its potential to address a number of challenges that today's electric utilities face, including increasing and changing electricity demand, shrinking operating capacity, and decreasing system reliability and flexibility. Being the least cost and least risky alternative, the share of energy efficiency programs in utilities' energy portfolios has been on the rise since the 1980s, and their increasing importance is expected to continue in the future. Despite holding great promise, the ability to determine and invest in only the most promising program alternatives plays a key role in the successful use of energy efficiency as a utility-wide resource. This issue becomes even more significant considering the availability of a vast number of potential energy efficiency programs, the rapidly changing business environment, and the existence of multiple stakeholders. This dissertation introduces hierarchical decision modeling as the framework for energy efficiency program planning in electric utilities. The model focuses on the assessment of emerging energy efficiency programs and proposes to bridge the gap between technology screening and cost/benefit evaluation practices. This approach is expected to identify emerging technology alternatives which have the highest potential to pass cost/benefit ratio testing procedures and contribute to the effectiveness of decision practices in energy efficiency program planning. The model also incorporates rank order analysis and sensitivity analysis for testing the robustness of results from different stakeholder perspectives and future uncertainties in an attempt to enable more informed decision-making practices. The model was applied to the case of 13 high priority emerging energy efficiency program alternatives identified in the Pacific Northwest, U.S.A. The results of this study reveal that energy savings potential is the most important program management consideration in selecting emerging energy efficiency programs. Market dissemination potential and program development and implementation potential are the second and third most important, whereas ancillary benefits potential is the least important program management consideration. The results imply that program value considerations, comprised of energy savings potential and ancillary benefits potential; and program feasibility considerations, comprised of program development and implementation potential and market dissemination potential, have almost equal impacts on assessment of emerging energy efficiency programs. Considering the overwhelming number of value-focused studies and the few feasibility-focused studies in the literature, this finding clearly shows that feasibility-focused studies are greatly understudied. The hierarchical decision model developed in this dissertation is generalizable. Thus, other utilities or power systems can adopt the research steps employed in this study as guidelines and conduct similar assessment studies on emerging energy efficiency programs of their interest.