Fig. 1: Oil Gusher
Oil wells located primarily in the Gulf Coast region contain an untapped and relatively unknown form of renewable energy called geopressure. Fluids from these wells rise naturally to the surface under extreme hydraulic pressure (4,000 -12,000psi) as evidenced by large gushers accompanying new oil discovery -e.g. the BP blowout disaster. Presently this form of energy is but a nuisance to well operators, being completely dissipated through a series of pressure letdown valves.
The Gulf Coast contains approximately 5,000 MW of geopressure energy worth $2.1 billion in annual wholesale electricity sales. The region has over 1.5 million wells already in the ground with over 150,000 exhibiting geopressure without the necessity of ever drilling another expensive new well.
Helidyne's geopressure reduction generator (PRG) converts this hydraulic form of energy into useful, emission free electricity. Its patent pending helical tri-rotor design (see concept animation below) processes geofluids directly in a self-cleaning manner. Scale and other containments that normally build-up on part surfaces are swept away by novel rotor sweeping action. In addition, fluid pressure is fully contained within the rotor cavity itself, completely isolating and protecting critical shaft seals and bearings from this harsh operating environment.
Figure 2: Tri-Rotor Concept
Helidyne is the only company to offer a design capable of harnessing this form of hydraulic energy. Owners of abandoned wells (those producing mostly water) can now re-tap this overlooked resource and reap value created by this technology. In addition, on-shore and off-shore wells that are currently in oil production can satisfy their remote power needs in a cheaper greener way.
Figure 3: Abandoned Oil Well
Once geofluids have been processed to generate electricity, they are returned via an injection well to a non-pressurized rock formation at a depth sufficient to ensure protection of fresh ground water resources.
Figure 4: Geopressure Power Plant
Due to the extreme pressures found in geopressure wells, a tri-rotor arrangement is preferred for increased rotor strength. Notice the thicker cross-section across the throat of the tri-rotor as compared to Helidyne's quad-rotor used for geothermal as shown in Fig.6 in the Geothermal Technical tab.
Pressure Reduction Generator Features:
• Up to 5,000 psi per stage; can be placed in series to utilize pressures over 12,000 psi
• Shaft seals exposed to low pressure
• High flow-rate, self-cleaning rotor design
• Dual rotors per shaft cancel axial thrust forces to reduce bearing load and torque pulses
• Oil-free design
• Direct generator coupling with 1800 rpm operating speed
• Production units starting at 250 kW, 300 gpm