Elemental Infusions are a type of Remnant in Path of Exile 2.

Fire Infusion icon
Elemental Infusions are a type of Remnant in Path of Exile 2.

Fire Infusion icon
Elemental Infusions are a type of Remnant that appear on the ground and can be collected by walking over them. Elemental Infusions can appear as a result of using a specific Skill, or by interacting with a Skill's mechanics. Upon collecting the Remnant, its Elemental type will be stored as an Infusion counter on your character.
There are currently three types of Elemental Infusions: Fire, Cold and Lightning.
Some Skills create Elemental Infusions at the end of their Duration, or under specific conditions. For example
Orb of Storms will generate Lightning Infusions when casting a number of Spells in its area, whilst
Frost Bomb will generate a Cold Infusion when it explodes.
Stored Elemental Infusions can be spent to improve some Spell Skills. For example
Ice Nova can consume a Cold Infusion to make it deal more Damage and create an area of Chilled Ground. Another example is
Ember Fusillade which can consume a Lightning Infusion to cause each Ember to emit a beam of chaining Lightning Damage.
Rarely, a Skill will be able to consume multiple different types of Elemental Infusions, such as
Firestorm which can consume a Fire Infusion to cause the storm's area to be twice as large and create three times as many bolts. It can also consume Cold and Lightning Infusions to cause the storm to create additional Cold and Lightning bolts. Notably
Firestorm is not limited to only consuming one Elemental Infusion, and can instead consume one of each type per cast to cause all additional effects simultaneously.
A stored Elemental Infusion will last for 20 seconds on your character by default. Picking up another Elemental Infusion of the same type before an older one expires will refresh the Duration of all Elemental Infusions of that type.