This mod is about living off the land of the various planets found throughout the Persean Sector. You can always stock up on enough fuel and supplies to circumnavigate the sector three times, but I find that it is much more enjoyable to acquire the resources I need as I explore. The drive field anomaly is a (completely optional!) game mechanic that provides an incentive for that playstyle. To dramatically oversimplify it, the anomaly causes certain conditions to convert your fuel into Anomaly Data, a new commodity that takes up no cargo space (making it as good as credits as long as you live long enough to sell it).
Anomaly data can be acquired by performing certain planetary operations, but the best way to get it is by studying the drive field anomaly. Unfortunately, this means allowing the anomaly to interfere with your drive field, and therefore your fuel supply. As you travel further through hyperspace, the anomaly will advance to increasingly dangerous stages and drain your fuel at a higher and higher pace. This will continue until you dock at any market, which will reset the anomaly to its initial, harmless stage. Thankfully, fuel stored in military-grade ships is protected from the increased fuel consumption caused by the anomaly. Ships with militarized subsystems suffer half the effect. This means tankers become less useful the further you travel.
To compensate for this effect, fuel lost due to the increased consumption rate is replaced by anomaly data of equal value. If you make it far enough you will also begin to accrue data simply for traveling through hyperspace. More data can be collected in this way by increasing the sensor strength of your fleet. With the right fleet, it can be very profitable to mount prolonged scientific exploration expeditions.
It's worth paying close attention to the "Drive Field Anomaly" intel item if you want to learn to take advantage of the anomaly. The anomaly is rather complicated, but I've done my best to explain things clearly and provide relevant info. In the screenshot below, my fleet has a total of 553 fuel, but only 283 of it is stored in militarized civilian ships. Once I have only 270 fuel my fleet's fuel consumption will return to normal, regardless of the anomaly stage.