During the last three decades it has mainly been achieved by the economy of scale consisting in increasing the cell dimensions allowing for higher current and therefore increasing the plant production and productivity. <...> This paper presents under which conditions a step change can be achieved without increasing the shell dimensions. <...> The design of a cell of the future is discussed in term of voltage distribution, heat loss, energy saving, productivity and environmental consequences. <...> Электролизер мечты: 1’000’000 ампер Rene V. Kaenel, Jacques Antille, Louis Bugnion, Laure V. Kaenel Kan-nak S.A. PO Box 477, CH-3960, Route de Sion 35, Sierre, Щвейцария Алюминиевая промышленность постоянно изыскивает способы снижения производственных затрат. <...> All rights reserved * Corresponding author E-mail address: rene.vonkaenel@kannak.ch # 802 # Rene V. Kaenel, Jacques Antille… 1’000’000 Amperes Deram Cell Introduction During the last three decades, the line current in aluminium reduction plants has increased considerably and has reached 600 kA. <...> During the same period all smelters have been active at increasing the productivity in their existing shell by increasing the anode size and the anode current density. <...> This was achieved by better cathode and collector bars designs sometimes combined with busbars modifi cations to improve the cell magneto-hydrodynamic stability. <...> A better magneto-hydrodynamic cell state allows decreasing the anode to cathode distance (ACD) needed for achieving the right thermal balance. <...> In the best case it has reached 80% depending on the initial state of the cell technology and level of optimization. <...> During the same period the current effi ciency has also improved and the best technologies achieve results close to 96%. <...> When analyzing the evolution of the specifi c energy consumption (E), a decrease from above 14 kWh/kg to 13 kWh and lower was achieved in many smelters. <...> The theoretical energy consumption can be expressed as: E = 1.431 / η + 4.915 [kWh/kg] (1) where η is the current efficiency. <...> The energy efficiency of the Hall-Hйroult process is low as shown in Table 1. <...> It is reasonable to ask ourselves what can be done to further improve the plant productivity. <...> Would it <...>