Large-scale integration of renewable energy in the electricity grid creates issues such as intermittency and lack of load and peak matching. Battery storage and nuclear energy are both low-carbon options that can supplement variable electricity generation and will be necessary for large-scale renewables deployment. However, with changes in resources and technology, it is important to anticipate future issues that might arise with these energy options to ensure the low cost and carbon footprint of electricity. In this dissertation, the main aim is to conduct a prospective life-cycle assessment (LCA) of second-life electric vehicle batteries (SLBs) as energy storage and uranium extraction for nuclear energy in the US, to identify and mitigate unintended consequences. Current battery technologies, in particular lithium-ion batteries, are expensive and can increase the carbon footprint of the grid due to charge-discharge losses. A possible cheaper and greener alternative for energy storage is remanufactured SLBs that have reached end-of-life (EOL). With the increase in electric vehicle (EV) sales, a large number of batteries are expected to reach EOL in the near future. Although SLBs can have 70 to 80% of remaining capacity, it is unknown whether they will perform at par with new batteries in various applications. It is also unknown whether SLBs provide cost and carbon emission reduction compared to new batteries, nor is there any information on SLB demand. Accelerated life testing was conducted on EOL EV battery cells to assess their performance in residential energy storage, commercial fast-charging, and utility-level peak shaving applications. A LCA and an economic evaluation were conducted to calculate the life-cycle carbon footprint and levelized cost of electricity of using SLBs and new batteries in the above-mentioned applications. A system dynamics model was developed to compare the cost, carbon footprint, and material requirement of EV battery recycling and remanufacturing in the US from 2017 to 2050. Residential energy storage performed the best during the accelerated life testing of battery cells. SLB use instead of new batteries can reduce the levelized costs and carbon footprint for all three applications. Remanufacturing reduced the life-cycle carbon footprint of batteries by 2 to 16% compared to recycling only. The economic value of remanufacturing is expected to decrease over time with the decreasing price of new batteries, necessitating policies that can incentivize SLB uptake, given that the SLB market is still emerging. In contrast, nuclear energy is a mature technology in use since the 1950s. Over time, uranium ore grades have decreased globally, and open-pit and underground mining methods are being replaced by in-situ leaching (ISL)—alkaline and acidic. Alkaline ISL is most prominent in the US and is promising for many recently discovered uranium deposits. As future uranium mines can be expected to use alkaline ISL, assessing its environmental impacts is necessary to assess those of future nuclear power plants in the world. Currently, there is no environmental LCA for alkaline ISL. We performed the first LCA of alkaline ISL in the US for extracting US-based uranium ores of grade 0.036-0.4% U3O8. The alkaline ISL carbon footprint was found to be almost twice those reported for acidic ISL, but lower than open-pit and underground methods. The results indicate a risk of increasing the carbon footprint of future nuclear energy generation. Similarly, the results for SLB-based applications show lower cost and carbon emissions compared to new batteries. It is important to identify anticipated future changes in resources or technology and include them in the present-day sustainability analysis of electricity generation. Prospective life-cycle assessment is, thus, a key analysis tool to analyze various low-carbon energy options to ensure the low cost and environmental impacts of electricity generation today and in the future.
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