A family of exciting new Electric Submersible Pump (ESP) technologies promises to radically improve the development economics of many oilfields and field extensions. This technology is particularly relevant to prospects in the range 5-100 million barrels reserves, which are located greater than 15 kilometres from existing platforms and often suffer uncertainties on reservoir performance (pressure, sweep, heterogeneities inflow performance etc.). Prospects in that category generally offer mediocre to inadequate economics or unacceptable risks of ‘downside’ potential. Platform development entails untenable capex exposure, whereas conventional subsea development (e.g. by gas lift) will result in very inferior production performance.
The new technologies which ‘unlock’ the economics of such fields are:
Viable subsea ESP technology is available now and will be field proven during 1994/95.
Proven high reliability pump systems are now available, underwritten by performance contract.
Bottom discharge pump systems offer powered ‘dump’ injection from an aquifer to the oil zone.
(This is a particularly efficient way of achieving water injection and obviates the tremendous weight penalty of conventional water injection systems).
Tandem pump versions of both conventional and bottom discharge systems offer much higher performance and assure long system life.
Multiple pump completions may offer the prospect of the cost effective ‘complete for life’ subsea ESP well in both conventional and bottom discharge mode.
These technologies offer superior technical and economic performance compared to existing, available methods, thus achieving enhanced development economics more robust to reservoir performance uncertainty.