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Photovoltaic capacity additions: the optimal rate of deployment with sensitivity to time-based GHG emissions

Description
Current policies subsidizing or accelerating deployment of photovoltaics (PV) are typically motivated by claims of environmental benefit, such as the reduction of CO2 emissions generated by the fossil-fuel fired power plants that PV is intended to displace. Existing practice is to assess these environmental benefits on a net life-cycle basis,…

Current policies subsidizing or accelerating deployment of photovoltaics (PV) are typically motivated by claims of environmental benefit, such as the reduction of CO2 emissions generated by the fossil-fuel fired power plants that PV is intended to displace. Existing practice is to assess these environmental benefits on a net life-cycle basis, where CO2 benefits occurring during use of the PV panels is found to exceed emissions generated during the PV manufacturing phase including materials extraction and manufacture of the PV panels prior to installation. However, this approach neglects to recognize that the environmental costs of CO2 release during manufacture are incurred early, while environmental benefits accrue later. Thus, where specific policy targets suggest meeting CO2 reduction targets established by a certain date, rapid PV deployment may have counter-intuitive, albeit temporary, undesired consequences. Thus, on a cumulative radiative forcing (CRF) basis, the environmental improvements attributable to PV might be realized much later than is currently understood. This phenomenon is particularly acute when PV manufacture occurs in areas using CO2 intensive energy sources (e.g., coal), but deployment occurs in areas with less CO2 intensive electricity sources (e.g., hydro). This thesis builds a dynamic Cumulative Radiative Forcing (CRF) model to examine the inter-temporal warming impacts of PV deployments in three locations: California, Wyoming and Arizona. The model includes the following factors that impact CRF: PV deployment rate, choice of PV technology, pace of PV technology improvements, and CO2 intensity in the electricity mix at manufacturing and deployment locations. Wyoming and California show the highest and lowest CRF benefits as they have the most and least CO2 intensive grids, respectively. CRF payback times are longer than CO2 payback times in all cases. Thin film, CdTe PV technologies have the lowest manufacturing CO2 emissions and therefore the shortest CRF payback times. This model can inform policies intended to fulfill time-sensitive CO2 mitigation goals while minimizing short term radiative forcing.
ContributorsTriplican Ravikumar, Dwarakanath (Author) / Seager, Thomas P (Thesis advisor) / Fraser, Matthew P (Thesis advisor) / Chester, Mikhail V (Committee member) / Sinha, Parikhit (Committee member) / Arizona State University (Publisher)
Created2013
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Negotiating (inter)disciplinary identity in integrative graduate education

Description
Identity, or peoples’ situated sense of self, can be conceptualized and operationalized in a myriad of ways, including, among others, a person’s gender, socioeconomic status, degree of expertise, nationality, and disciplinary training. This study conceptualizes identity as fluid and constructed through social interaction with others, where individuals ask themselves “Who…

Identity, or peoples’ situated sense of self, can be conceptualized and operationalized in a myriad of ways, including, among others, a person’s gender, socioeconomic status, degree of expertise, nationality, and disciplinary training. This study conceptualizes identity as fluid and constructed through social interaction with others, where individuals ask themselves “Who am I?” in relation to the people around them. Such a discursive conceptualization argues that we can observe peoples’ performance of identity through the close reading and examination of their talk and text. By discursively drawing boundaries around descriptions of “Who I am,” people inherently attribute value to preferred identities and devalue undesirable, “other” selves. This study analyzes ten workshops from the Toolbox Project conducted with graduate student scientists participating in the Integrative Graduate Education Research Traineeship (IGERT) program. The emotional tone, mood, and atmosphere of shared humor and laughter emerged as a context through which collaborators tested the limits of different identities and questioned taken for granted assumptions about their disciplinary identities and approaches to research. Through jokes, humorous comments, sarcasm, and laughter, students engaged in three primary forms of othering: 1) unifying the entire group against people outside the group, 2) differentiating group members against each other, and 3) differentiating oneself in comparison to the rest of the group. I use action-implicative discourse analysis to reconstruct these communicative practices at three levels—problem, technical, and philosophical—and explore the implications of group laughter and humor as sites of “othering” discursive strategies in graduate students’ efforts to negotiate and differentiate identity in the context of integrative collaboration.
ContributorsHinrichs, Margaret M (Author) / Tracy, Sarah J. (Thesis advisor) / Seager, Thomas P (Thesis advisor) / Hannah, Mark A (Committee member) / Arizona State University (Publisher)
Created2016