Talk:National Ignition Facility/Laser efficiency

The following may be helpful in understanding the conversion of electricity to laser light and various derivations of "wall plug efficiency" printed after the December 5, 2022 breakeven fusion shot.

Engineering breakeven in a laser inertial fusion setup – net electrical power generation – is achieved approximately when the fusion gain multiplied by the drive laser efficiency equals 1. In the case of the December 5 breakeven shot, 1.5 × 0.0066 = 1% (roughly). This is why commentators have stated it needs to gain two orders of magnitude somewhere to become a meaningful fusion power source.

However, note that the report cited below also says that one order of magnitude improvement can be made by replacing the flashlamps with diodes for laser pumping, and a more-or-less complete redesign can result in 20x gain over the original NIF design. So maybe "just" another order of magnitude improvement in fusion gain is required.

NIF drive laser efficiency
The report where this table appeared used the term "drive laser efficiency" which appears to be interchangeable with the definition at wall-plug efficiency.

The "lamp-pumped" column is for the current (as of 2022) NIF design using flashlamp pumping. The "diodes" column is for an upgrade using laser diodes instead, making it a diode-pumped solid-state laser.