'energy-neutral' originates from Modern English as a compound of 'energy' and 'neutral'. 'energy' ultimately comes from Greek 'energeia' (ἐνέργεια), where 'en-' (ἐν-) meant 'in' and 'ergon' (ἔργον) meant 'work' or 'activity'; 'neutral' comes via Latin 'neutralis' from neuter meaning 'neither of two'.

'energy' passed from Greek 'energeia' into Latin and Old French (Middle English forms like 'energie') and became the modern English 'energy'; 'neutral' passed from Latin 'neutralis' into Old French and Middle English ('neutral') and kept a sense of 'neither of two'. The compound 'energy-neutral' is a modern English coinage formed by combining these words.

Initially, 'energy' meant 'activity' or 'operation' and 'neutral' meant 'neither of two sides'; over time 'energy' acquired its modern physical sense (capacity to do work) and 'neutral' kept the sense of 'no net effect', so the compound evolved to mean 'having no net energy change'.