UC Merced

Carbon dioxide emissions represent the primary driver behind the accelerated global warming problem. While mitigating these emissions from key sectors may necessitate a protracted timeframe, several promising technologies offer the potential for short-term advancements in full or partial decarbonization efforts. In pursuit of establishing a sustainable and reliable zero-carbon energy system, the deployment of energy storage systems integrated with clean and renewable resources becomes imperative. Solar and wind technologies are ubiquitously available across numerous nations and have attained a level of maturity conducive to widespread deployment on a grid scale. The combination of solar and wind energy with energy storage serves to expedite the decarbonization of electricity generation processes. Notably, the industrial and transportation sectors are difficult to be decarbonized, requiring decades to decarbonize due to the imperative of either developing novel technologies or optimizing existing ones to boost efficiency and cost-effectiveness. Giving priority to decarbonizing processes or sectors that can be mitigated relatively easily accelerates the broader decarbonization of more complex counterparts, thereby promoting a comprehensive approach to carbon mitigation strategies.The electricity generation is an important first step in decarbonizing the rest of sectors. In this dissertation, I investigated the challenges and the potential solutions for decarbonizing the electricity generation using clean and renewable sources of energy. Furthermore, I explored the possibility of decarbonizing some of the industrial processes using solar thermal technology. Eventually, I proposed the possible opportunity for Direct Air Carbon Capture (DACC) for indirect decarbonization of other hard-to-be-decarbonized processes/sectors like steel and cement industry and aviation sector. To achieve 100% renewable electricity grid, all the carbon emitting resources are replaced by a renewable resources like solar and wind for all the years from 2015 to 2020. The real historical demand and generation data are used. We explored various 100% renewable electricity grid scenarios by using different mixes between the available renewable resources (solar, onshore wind, offshore wind, and geothermal) with different overbuild capacities. Our findings indicate that while summer currently poses the greatest challenge, a solar-dominant grid shifts this challenge to the winter, contingent upon solar and storage capacities. To reduce the storage size and decrease the severity of the winter challenge, we investigated the potential of winter-dominant onshore wind and the usage of a clean dispatchable source of energy like the Allam cycle sequentially. We found that the storage size can be reduced by 30%-40% and we can generate about 37% of the total annual electricity consumption using the available winter-dominant onshore wind. Further analysis of the energy storage indicates that part of it is used frequently every day to supply the electricity demand during the nights (diurnal storage) and another big part of it is used to compensate the limited solar generation during the winter (seasonal storage). The rest of the energy storage is used to cover the cloudy days across the year (cross-day storage). Decarbonizing the industrial sector will add to the current electricity demand. Thus, we investigated the possibility of decarbonizing some of the industrial processes using solar thermal technology that does not rely on the electricity grid. We presented a comprehensive assessment of the performance of a novel solar thermal system, the Non-tracking Asymmetric Shadeless (NASH) concentrator, highlighting its efficiency and energy generation capabilities. A steady-state model developed for the system offers valuable insights into its operational dynamics and performance trends. Other industrial processes and sectors are hard to decarbonize, (e.g. the steel industry, the cement industry, and the aviation sector). It may take decades to decarbonize these processes/sectors. We proposed that we use Direct Air Carbon Capture (DACC) to capture the carbon emissions from these processes/sector. The DACC will be powered by the surplus electricity generated by a 100% renewable electricity grid. By combining empirical data analysis with theoretical modeling, this dissertation contributes to advancing our understanding of the challenges and the potential solutions for decarbonizing electricity generation, offering crucial insights for policymakers and stakeholders navigating the transition to sustainable and reliable clean energy systems.