This research will utilize the energy and poverty alleviation framework to investigate a sustainable energy ecosystem for the Wakapoa indigenous community of Guyana. Five questions guide the research – 1) Is there an energy access-development nexus? 2) Can the relationships and trends between key development indicators and electricity access guide policymakers on development activities? 3) Can small-scale concentrated solar and biomass systems provide adequate electrical power to meet the Wakapoa community's domestic and commercial loads economically? 4) What added social value could be generated from the energy system as per Wakapoa context? and 5) What governance systems can be considered to facilitate a sustainable energy ecosystem? In addressing questions 1 and 2, the research collected secondary data on selected countries' key development indexes from the World Bank and Our World in Data. Datasets include the human development index, human capital index, gross domestic product per capita, gross national income per capita, and electricity access. In addressing questions 3 to 5, the research utilized the convergent research design methods, where an inclusive data collection process targeted fifty (50) community residents as survey participants. Statistical analysis of the survey data proved useful in identifying the community needs for the renewable energy system design options utilizing system advisor model (SAM) software, identifying key economic activities that can add social value to the community, and giving key insight into governance practices preferred by the community. Key findings reveal that electricity access exerts a strong and moderate influence on key development indicators, the concentrated solar power and biomass hybrid system can satisfy the electricity demand of the community at the Tier-5 level that can support many traditional and non-traditional economic activities, while key governance support functions such as the community financial aid fund and community management committee can enhance the sustainability of the various operations as well as residents' well-being and livelihood. Future research can address project financing, community productive capacity, and the marketing of goods and services to promote a sustainable energy ecosystem.

Climate change poses a serious challenge humankind. Society’s reliance on fossil fuels raises atmospheric CO2 concentrations causing global warming. Already, the planet has warmed by 1.1 °C making it nearly impossible to heed the advice of the IPCC (2022) and prevent warming in excess of 1.5 °C by 2050. Even the current excess of CO2 in the atmosphere poses significant risks. Direct air capture (DAC) of CO2 offers one of the most scalable options to the drawdown of carbon. DAC can collect CO2 that is already diluted into the atmosphere for disposal or utilization. Central to most DAC are sorbents, i.e., materials that bind and release CO2 in a capture and release cycle. There are sorbents that cycle through a temperature swing. Others use a moisture swing, or a pressure swing or combinations of all of them. Since DAC is still a nascent technology, advancement of sorbents is an important part of DAC development. There is a nearly infinite combination of possible sorbents and form factors of sorbents that can be deployed in many different variations of DAC. Our goal is to develop a methodology for characterizing sorbents to facilitate rational choices among different options. Good sorbent characteristics include high capacity, fast sorption and desorption kinetics, low energy need for unloading, and longevity. This work presents the development of a systematic approach to evaluate sorbents from the milligram to tonne scale focusing on the important characteristics mentioned above. The work identified a good temperature swing sorbent whose characterization moved from the mg to kg scale without loss in performance. This work represents a first step in systematizing sorbent characterization for rational sorbent development programs.

Solar energy is a disruptive technology within the electricity industry, and rooftop solar is particularly disruptive as it changes the relationship between the industry and its customers as the latter generate their own power, sell power to the grid, and reduce their dependence on the industry as the sole source provider of electric power. Hundreds of thousands of people in the western United States have made the decision to adopt residential rooftop solar photovoltaic technologies (solar PV) for their homes, with some areas of western cities now having 50% or more of homes with solar installed. This dissertation seeks to understand how rooftop solar energy is altering the fabric of urban life, drawing on three distinct lenses and a mixed suite of methods to examine how homeowners, electric utilities, financial lenders, regulators, solar installers, realtors, and professional trade organizations have responded to the opportunities and challenges presented by rooftop solar energy. First, using a novel solar installation data set, it systematically examines the temporal, geographic, and socio-economic dynamics of the adoption of rooftop solar technologies across the Phoenix metropolitan area over the decade of the 2010s. This study examines the broad social, economic, and urban environmental contexts within which solar adoption has occurred and how these have impacted differential rates of solar uptake. Second, using survey and real estate data from the Phoenix metropolitan area, it explores how solar energy has begun to shape important social and market dynamics, illuminating how decision-making in real estate transactions, including by buyers, sellers, agents, lenders, and appraisers is shifting to accommodate houses with installed solar systems. Lastly, the study explores patterns of rooftop solar adoption across major electric utilities and what those can tell us about the extent to which corporate social responsibility and sustainability reporting have affected the practices of investor-owned electric utilities (IOU) within the western US.