Online Archive of University of Virginia Scholarship
Reaching 10 Kelvin: Precision Thermal Metrology; The Hidden Cost of Clean Transportation: A Socio-Technical Analysis of Electric and Hybrid Vehicles7 views
Author
Rojas Ramirez, Andrea, School of Engineering and Applied Science, University of Virginia
Advisors
Scott, Ethan, EN-Mech & Aero Engr Dept, University of Virginia
Francisco, Pedro Augusto, EN-Engineering and Society, University of Virginia
Abstract
Engineering solutions are often presented as answers to major societal problems, but the success of any technology depends not only on technical performance, but also on how it is understood, implemented, and experienced by society. My capstone project focuses on designing and repurposing a cryogenic pump into a functional cryostat capable of replicating the 3⍵ experiment used to measure thermal conductivity from room temperature and down to 10 Kelvin. This project was undertaken to create an efficient system capable of reaching temperatures near 10 Kelvin. The STS component examines how electric and hybrid vehicles are marketed as environmentally friendly technologies while the environmental and social harms of their production are often obscured. This research explores how public discourse and corporate narratives shape perceptions of sustainability and technological progress. There are no ties between both projects, but are both relevant for the field of mechanical engineering. My capstone project focuses on designing and improving a cryogenic system, which can further research in heat transfer and the accurate measuring of thermal conductivity. The STS research highlights the responsibility many engineers, including mechanical engineers, have to consider the ethical, environmental, and societal impacts of technologies they help design.
The capstone component is predominantly a technical challenge of creating a cryogenic testing system capable of replicating the 3⍵ experiment, a technique used to measure thermal conductivity of material. Our team was divided into structural, experimental, vacuum, and electrical to complete a mounting system for the cryostat. Furthermore, our team was tasked to create a high vacuum environment nearing 10^(-8) Torr while also troubleshooting the compressor. The electrical group focused on wiring the cryostat which was needed to obtain temperature and current measurements.
Our team was able to perform the 3⍵ experiment at room temperature, where the thermal conductivity of Corning SiO2 7980 was determined to be 1.4 W/(m∙k) which is on par with manufacture specification of 1.38 W/(m∙k). However, our team was unable to reach our 10 Kelvin goal due to the compressor not fully operating at optimal conditions. The final temperature our system reached was 238 K with our vacuum reaching 7.3 ∙10^(-6) Torr. Further troubleshooting of our compressor will allow for the 3⍵ experiment to be implemented at lower temperatures with the system created.
The STS component explores how marketing practices and public discourse portray electric and hybrid vehicles as environmentally friendly technologies while overlooking their environmental and social harms. This research is significant because electric vehicles are widely promoted as solutions to climate change, yet their production depends on resource intensive mining, exploitative labor conditions, and energy systems reliant on fossil fuels. The framework used to analyze this research was Social Construction of Technology as it allowed how different social groups shaped the meaning of technology. The methodology used included document analysis analyzing advertisements, reports, and media coverage, along with a general ethical reflection.
The evidence of the STS component shows that electric and hybrid vehicles are often presented through selective marketing that emphasizes specs and positive impacts while ignoring lifecycle impacts of these vehicles. Companies used vague environmental claims and symbolic imagery to create the perceptions of sustainability without fully addressing underlying harms. This selective framing shifts responsibility from corporations to consumers, encouraging people to see their purchasing power as meaningful climate action while larger structural issues remain unaddressed.
Degree
BS (Bachelor of Science)
Keywords
Thermal Metrology; Hybrid Vehicles; Electric Vehicles; 3-Omega; Thermal Conductivity
Notes
School of Engineering and Applied Science
Bachelor of Science in Mechanical Engineering
Technical Advisor: Ethan A. Scott
STS Advisor: Pedro Augusto P. Francisco
Technical Team Members: Brandon Flores Castaneda, Hannah Heafner, Jimmy Bastos Infantas, Jimmy Chen, Jonathan Martinez, Mary Cotter, Matthew Orellana-Aquino, Mia Petersen, Mohammad Ahmadzai, Philip Li, Raymond Ni, Tristan Huynh
Language
English
Rights
All rights reserved by the author (no additional license for public reuse)
Rojas Ramirez, Andrea. Reaching 10 Kelvin: Precision Thermal Metrology; The Hidden Cost of Clean Transportation: A Socio-Technical Analysis of Electric and Hybrid Vehicles. University of Virginia, School of Engineering and Applied Science, BS (Bachelor of Science), 2026-05-01, https://doi.org/10.18130/9tbv-n484.