The Bussard collectors, also known as Bussard ramscoops, are the primary backup fuel replenishment system on board Federation starships when deuterium tanker resupply is not an option, the starship is out of resupply range, or the starship is in distress.

The Bussard collectors are mounted on the front of the warp nacelles on all Federation ships. The collectors are designed to trap the small amounts of free interstellar hydrogen to replenish the ships diminishing reserves of deuterium, thus staving off disaster until proper resupply can be accomplished. Even though the density in interstellar matter is very low, approximately one atom per cubic centimeter, traveling at warp velocities can produce sizable quantities of deuterium. The Bussard collectors are also designed to work in conjunction with the navigational deflectors which normally sweep away small particles in the path of the ship such as deuterium atoms.

The collectors work by emitting an ionizing radiation beam that changes the charge of the surrounding neutral gas; at warp velocities this beam can be emitted into subspace so it propagates out in front of the ship. The Bussard collectors also emit a shaped magnetic field around the ship to funnel the now charged gas into the collectors. Finally the collectors separate the useable fuel from the low grade matter, the deuterium is then transferred to the deuterium storage tanks for use by the warp engines.

Other nonconventional uses of the Bussard collectors have included emitting matter streams into space and as a defensive weapon against attacking ships.