Life energy

Life energy is a type of biological energy required for life.

In the 21st century on Earth, the Leiber-Kurtzberg Theory proposed the existence of life energy. Because proof could not be found at the time, the theory was discredited. 

Examples
In Bajoran theology, a person's life energy is stored in their pagh. 

Thousands of years ago, a Giant Brain organism living within the core of an unnamed asteroid began injecting large quantities of life energy into the lifeforms on the surface, which helped sustain them. 

In 2266, life energy was drained from the planet Ecnal by a Lerow rocket intent of using it to restore life on their dying Lerow homeworld. The Federation starship USS Enterprise (NCC-1701) provided its crew with an energy converter so it didn't need to steal the life energy. 

In the 2260s, the core of Tristas was found to be hollow, containing a vast field of life energy. Proximity to it merged six scientists into a group consciousness. In 2267, Admiral Tailen Kahn briefly connected with the life energy field, leaving him visibly shaken and notably changed. 

In 2269, a life energy transfer device built by Ylterans was discovered on Camus II. An exchange of life energy between two people connected to the device resulted in identity transference. 

Species/Entities that drain life energy

 * Beavo (Selkye)
 * Crystalline Entity (SS SNW (Guardians))
 * Devidians (Devidia II)
 * R'kaal
 * Hollow Planet
 * Mortard robots (Raylo)
 * Space amoeba
 * Tactisian (Tactis II asteroid)
 * Taurean colonists

In a Klingon interpretation of historical events played out in a holosuite, (*) was said to drain life energy rather than subsist on strong emotions such as hate. (SS SNW (Guardians))