The name Energa comes from the firm in Liechtenstein that designed it, the Anstalt für die ENtwicklung von ERfindungen und Gewerblichen Anwendungen, based in Vaduz.

[3] First produced in the 1950s, by Mecar in Belgium, it was in front-line use by European armies until replaced by disposable tube-launched anti-tank rockets such as the M72 LAW.

The Super Energa used a rocket booster to extend the grenade's range to 550 m (1,800 ft).

The M28 was eventually replaced in US military service by the M31 HEAT rifle grenade and later by the M72 LAW rocket.

The Energa was introduced to infantry units of the British Army of the Rhine from 1952 when it replaced the PIAT.

It was launched from the standard Vektor R1 (South African version of the FN FAL) rifles.

[4] Bangladeshi Mukti Bahini members used Energa grenades in a large number during the Bangladesh Liberation War.