Geopressured-Geothermal brines (GPGT) are an immense energy resource that remain relatively untapped throughout the world. Per U.S. Geological Survey estimates, there are 5,700 quads of recoverable gas and 11,000 quads of available thermal energy in the Gulf Coast GPGT basin alone. For comparison, the U.S. total annual energy consumption (c. 2003) is estimated at 100 quads.

• GPGT: High pressure, high temperature, gas cut, brine reservoirs
  • wellhead pressure: 1000-4000 psi
  • brine temperature: 250-400F
  • GPGT brines contain 20-100 scf/bbl natural gas
  • normally found at depths greater than 10,000 feet
  • can be produced at high flow rates: 20,000-40,000 bbl/day
  • GPGT brines contain 15,000-200,000 ppm dissolved solids, typically 85% NaCl
  • outstanding flow longevity (Dept. of Energy flow tests, Gulf Coast region)
    
    
• The recoverable GPGT energies are
• thermal (heat exchange with brine)
• mechanical (flowing pressure at wellhead)
• chemical (natural gas)
  
  
• U.S. GPGT regions are strategically collocated
• GPGT collocated with medium-to-heavy U.S. oil reserves
• California/Gulf Coast GPGT collocated with water crisis regions (Water 2025)

Not to be confused with "hot-rock" geothermal