RE: Tonight's View3 Jul 2021 19:26
DC,
"If the warning of a continued decline in production was not just scaremongering the what was the point of installing the ESP’s?"
Ouch ! That's an awkward sort of 64,000-dollar question. I'll try to make my answer (opinion) brief, though may not succeed in that. Naturally I'd welcome connent, criticism, or downright contradiction of what I write by others.
For me, the ESP's are there not simply for 'enhanced production', but equally for well longetivity. Costs more to start with, but ensures no (very expensive, with field production shutdowns workovers) later. 75 percent of 'Series' Landrovers are still on the road, or at least still existent. 98 percent of Auastin Maestros have been 'recycled' and now comprise part of your fridge. That sort of thinking.
The well design is 'landrover-style' good. Tandem ESP's is just for redundency purposes. If one breaks, the other can be used. Never the two at the same time. Just like a cave-diver always has two sets of tanks, regulators, etc.. If one 'goes', he or she can swap over. If not, they're dead.
But why ESP's in the well to start with? Good question. But yet again, it's part of the 'belt and braces' approach from the start. More expensive for sure, but again ensuring a certain well longetivity and lifetime.
Without being unduly negative, almost no oilwell will not see a certain productivity-decline over time. Also, near-wellbore pressures may drop. HOWEVER, one simply cannot extrapolate and say (as the latest CPR tends to) that 'reservoir pressure' has dropped, unless one has another well, some distance away, from which to measure that. And it ain't the case so far on Lancaster, and also Fractured Basement being what it is, a measurement from one well may not reflect overall reservoir pressure.
ESP's also give the operator a lot more 'control' over things. On a well which flows 'naturally', one only really has one control element, which is the surface choke. The well may decide to 'slug' some gas, water, or whatever, and there isn't much to be done about it. Whereas with an ESP in the completion, other than the pump acting as a production-enhancer, it can also act (alongside the choke) as a sort of 'smoother'. As in this case, because they're variable-speed ESP's. This puts the well's behaviour under human control, rather than just that of Mother Nature.
OK, rabbitted on long enough, hope that helps. Time now to go out for a Saturday night drink !