The rapid energy depletion of the Tarxin Defense Network was fundamentally due to the destructive ray towers known as Wave Towers.
The Wave Towers, placed on the Skrull front lines, attacked ceaselessly, with each destructive ray destroying a shield panel, adding immense extra pressure to the defense network.
Without those towers, even with the Skrull fleet and high-ranking combatants alone, the energy reserves of the Tarxin Defense Network would diminish progressively, but not as quickly as they were currently.
Swift, after analyzing the damage data, did a quick calculation and realized that if things continued at this rate, the energy reserves of the Tarxin Defense Network would be exhausted within a month!
At that time, the Spirit Energy Storage Stations and the fusion power plants in the rear would be unable to support the energy needs of the defense network, whose defensive capabilities would see a significant drop or even a total collapse!