Page "Electrothermal-chemical technology" Paragraph 14

ETC is also a more viable option than other alternatives by definition.

ETC requires much less energy input from outside sources, like a battery, than a railgun or a coilgun would.

Tests have shown that energy output by the propellant is higher than energy input from outside sources on ETC guns.

In comparison, a railgun currently cannot achieve a higher muzzle velocity than the amount of energy input.

Even at 50 % efficiency a rail gun launching a projectile with a kinetic energy of 20 MJ would require an energy input into the rails of 40 MJ, and 50 % efficiency has not yet been achieved.

To put this into perspective, a rail gun launching at 9 MJ of energy would need roughly 32 MJ worth of energy from capacitors.

Current advances in energy storage allow for energy densities as high as 2. 5 MJ / m³, which means that a battery delivering 32 MJ of energy would require a volume of 12. 8 m³ ; this is not a viable volume for use in a modern main battle tank, especially one designed to be lighter than existing models.

There has even been discussion about eliminating the necessity for an outside electrical source in ETC ignition by initiating the plasma cartridge through a small explosive force.