exhaustless

adjective2

1. •
   Unable to be exhausted; having an endless supply; inexhaustible.

   • Nectar ran / In courteous fountains to all cups outreach'd; / And plunder'd vines, teeming exhaustless, pleach'd / New growth about each shell and pendent lyre; [...] — 1818
2. •
   Not producing exhaust.

   • These obstacles preclude near-future solutions for exhaustless vehicles, or those having an exhaust with greatly reduced toxicity. — 1969