A small air-cooled ion laser might produce, for example, 130 milliwatts of output light with a tube current of about 10 amperes and a voltage of 105 volts.
Subtracting the (desirable) light output of 130 mW from power input, this leaves the large amount of waste heat of nearly one kW.
Common argon and krypton lasers are capable of emitting continuous-wave (CW) output of several milliwatts to tens of watts.
The typical noble-gas ion-laser plasma consists of a high-current-density glow discharge in a noble gas in the presence of a magnetic field.
Typical continuous-wave plasma conditions are current densities of 100 to 2000 A/cm2, tube diameters of 1.0 to 10 mm, filling pressures of 0.1 to 1.0 Torr (0.0019 to 0.019 psi), and an axial magnetic field of the order of 1000 gauss.