## 1 Introduction
Another approach is the photocatalytic method that could use visible light directly [13], avoiding the associated carbon footprint of the energy conversion that it is still found at lower TRLs. On the other hand, ER of CO\({}_{2}\) is still behind in terms of TRLs compared to catalytic ways but has the advantage that it can be fully developed at atmospheric temperature and pressure in such a way that it can utilize surpluses of electricity from renewable sources [16; 17]. Despite the numerous advances and novel approaches in recent decades, the ER process remains challenging because of (i) the high overpotential needed, (ii) the high consumption of steam of the final separation step, (iii) the low solubility of CO\({}_{2}\) at both ambient temperature and pressure, and (iv) the deactivation and damage of the electrodes [18]. Continuous efforts are still required to achieve an efficient ER of CO\({}_{2}\) from the point of view of environmental sustainability. The development of highly active and durable electrocatalysts for both the cathode (CO\({}_{2}\) reduction reaction) and the anode (O\({}_{2}\) evolution reaction), as well as electrodes and electrolytes that have high conductivity and allow for sufficient mass transport of the reactants and products to/from the catalyst layers, are some of the key points to ensure environmental sustainability [19; 20]. A recent economic-viability study of four possible routes for the ER of CO\({}_{2}\) to liquid products (including FA) has demonstrated that the primary economic limiting factor is the high capital expense for the electrolyzer units [21]. Consequently, some technological challenges need to be overtaken to make ER alternative an industrial viable option. It is clear that several options are available and, at least, environmental sustainability must be analysed prior to any other economic or social consideration. In this study, Life Cycle Assessment (LCA) is used as a decision-making tool for process development, enabling the prediction of the sustainability implications of the different alternatives. LCA is a widely used tool that is used to evaluate the net contribution of the use of carbon dioxide [22; 23; 24; 25], and thus it can be used to compare the FA conventional process with both CO\({}_{2}\) utilization alternatives. In a previous study from the authors, it was concluded that the integration of renewable energy was required to ensure the potential environmental sustainability of FA by ER synthesis based on the champion lab data at the time of the study [26]. The results obtained in this study provide a complete overview of the remaining technological challenges, especially for the competitiveness of CO\({}_{2}\) utilization plants based on ER as it remains in its infancy. The technological aspects included in this study involve (1) reaction, by means of the concentration of FA at the outlet stream of the ER cell, the cell voltage, the faradic efficiency, and the mode of operation (i.e., recirculation); and (2) the separation step, by means of azeotropic distillation. This work aims to compare, in terms of carbon footprint, the FA commercial production process (fossil-based) with two of the main CO\({}_{2}\) utilization alternatives of FA synthesis (homogeneous catalysts and the novel ER of CO\({}_{2}\)) based on the latest available experimental developments [7; 14; 15]. Savings in terms of raw materials are also included for a more fair comparison. The novelty of this work relies on the use of new champion lab data, which show the tremendous progress taking place in the ER research field in order to check if current technological developments can even out the conventional production processes in terms of carbon footprint.