Based on a sample space of 724 storage configurations, we show that energy capacity cost and discharge efficiency largely determine the optimal storage deployment, in agreement with previous studies. This dramatic shift transforms the economics of grid-scale energy storage, making it an increasingly viable solution for Europe's renewable. . LFP spot price comes from the ICC Battery price database, where spot price is based on reported quotes from companies, battery cell prices could be even lower if batteries are purchased in high volume. Estimated cell manufacturing cost uses the BNEF BattMan Cost Model, adjusting LFP cathode prices. . endency on fossil fuels. Studies show that the increased deployment of storage reduces wholesale electricity prices a gy rges paid by grid users. These fees reflect the cost of both the grid infrastructure and of system operation.