How Carbon-Friendly Is Nuclear Energy? A Hybrid MRIO-LCA Model of a Spanish Facility

Abstract

Spain faces the challenge of 80-95% greenhouse gas emissions reduction by 2050 (European Energy Roadmap). As a possible first step to fulfill this objective, this paper presents a two-level analysis. First, we estimate the carbon footprint of a hypothetical nuclear facility in Spain. Using a hybrid multiregional input-output model, to avoid truncation while diminishing sector aggregation problems and to improve environmental leakages estimations, we calculate the CO2 equivalent emissions associated with the different phases of the nuclear life-cycle--construction, fuel processing and operation and maintenance--taking into account the countries or regions where the emissions have been generated. Our results estimate a nuclear carbon footprint of 21.30 gCO2e/kWh, of which 89% comes from regions outside Spain. In some regions, the highest impacts are mostly direct (92%, 95%, and 92% of total carbon emissions in the U.S., France, and UK, respectively), meaning that these emissions are linked to the inputs directly required for nuclear energy production; in other regions, indirect emissions are higher (83% in China), which becomes relevant for policy measures. Second, through the analyses of different scenarios, we unravel and quantify how different assumptions that are often taken in the literature result in different carbon emissions.

Carbon footprint of a university in a multiregional model: the case of the University of Castilla-La Mancha

“…This additional result will be compared with calculations with more aggregated coefficients. The first step of the hybridization is accomplished from the decomposition of the Leontief matrix in a power series as used previously by (Baboulet and Lenzen, 2010;Zafrilla et al, 2014), where each power of the technical coefficient matrix A indicates a layer of the production process as in equation (2):…”

“…The same technology assumption is unavoidable in single-region models (see (Ozawa-Meida et al, 2013) or (Thurston and Eckelman, 2011)), and the assumption of all imports being produced using the same technology, however different to the domestic one, is also considered (Larsen et al, 2013). The hybrid model combines the completeness of EEIOA, which avoids the truncation errors of pure P-LCA which results in systematic underestimation of the environmental load, with the accuracy of P-LCA by collecting more detailed information at some important points of the analysed activity or process (Lenzen and Dey, 2000;Suh, 2004;Suh et al, 2004;Weinzettel et al, 2014;Zafrilla et al, 2014).…”

Hybrid life cycle inventory methods – A review

“…This method, also often referred to as input-output-based hybrid, was originally proposed by Joshi (1999). It has, since then, been widely used in the literature Qiuhong et al, 2014;Wiedmann et al, 2011;Zafrilla et al, 2014).…”

Corporate and Product Carbon Footprint under Compound Hybrid Analysis: Application to a Spanish Timber Company

“…Second, a structural path analysis is used to fulfill the ISO/TS 14067 requirements related to process mapping and system boundaries. This method applies a power series expansion of the inverse following (Waugh ), as previously used by Baboulet and Lenzen (), Strømman and collegaues (), and Zafrilla and colleagues (). As equation shows, scope 3, those related to categories 9 to 16 and 23, emissions are distributed among individual components that add up to both the value chain and, consequently, the supply chain of products dispatched to the market: …”