In many sci-fi books, movies, and even games; the idea of having a gas giant as an unlimited source for fuel is always there. Using the hydrogen gas of the planet itself a ship can use it to create a reaction in the FTL to make it enter sub-space of speed up to the speed-of-light. Now there are two ways always shown in Sci-Fi. One is using special filters on the outside of the ship to filter the atmosphere’s hydrogen into the supply tank. Next is the refinery way. This is where the hydrogen gas is processed to where it is nearly 99% pure hydrogen which is later shipped off or collected by ships in orbit (which pay heavy prices for such fuel).
| Class | D% Roll | Hydrogen% | Other Gases % | |
| Small | 1 | 0-10% | 5% or less | 95% or more |
| 2 | 11-20% | 10% or less | 90% or more | |
| 3 | 21-30% | 15% or less | 85% or more | |
| 4 | 31-40% | 20% or less | 80% or more | |
| 5 | 41-50% | 25% or less | 75% or more | |
| 6 | 51-60% | 30% or less | 70% or more | |
| 7 | 61-70% | 35% or less | 65% or more | |
| 8 | 71-80% | 40% or less | 60% or more | |
| 9 | 81-90% | 45% or less | 55% or more | |
| Very Large | 10 | 91-00% | 50% or less | 50% or more |
Now the Class 1 gas giant is about the size of Earth or larger. Class 10 gas giants are five times bigger than Earth’s sun.
In order to filter the hydrogen into the ship’s reserve you need to have special filters. The higher the class the better they can filter out unwanted gases. The higher the class of filter the more energy it requires from the ship. So, remeber that a class six will either require a massive generator of some type, or a bigger ship.
| Filter Class | *Cost (USD) | Filter % |
| 1 | 200,000 | 5-10% or unwanted gases |
| 2 | 500,000 | 15% of unwanted gases |
| 3 | 1,000,000 | 30% of unwanted gases |
| 4 | 1,500,000 | 60% of unwanted gases |
| 5 | 2,000,000 | 90% of unwanted gases |
| 6 | 2,500,000 | 99.99% of unwanted gases |
* Convert to whatever currency your game uses (this is just a BS number really).