Whitepaper Stellarium

The Essence

A plasma-like space substance ... almost ethereal
Essence is the main and vital resource of our universe, it is what allows us to move the large HSP space engines for travel at the speed of light, which implies being able to reach places so far away that otherwise it would be impossible, that is why it is the most valuable resource for which many venture to discover new expedition locations and others are hardened in battles to win said treasure, defeating their opponents either in official tournaments or assaulting space freighters.
The Essence is very unstable so it must be processed quickly, small ships cannot install an essence concentrator so they must take it immediately after its collection to the refinery, this module of the Prometheus station is the one in charge of processing ( refine) the essence to become the fuel for the medium and small ships, since the large ones can install their own concentrator and process the essence immediately after extraction, thus avoiding the trip to the refinery.