Aquifer or Depleted Reservoir Storage Flow Diagram
At depths of 1,500 feet or more, the free pore space of a suitable rock formation can be often used for storage of natural gas or compressed air. The rock formation layer must be adequately porous or fissured with good permeability and have an impermeable overburden which will not let the stored gas escape either vertically or laterally. Generally speaking, sandstones, dolomites, porous limestones or fractured rocks are suitable for such storage.
Storage space in an aquifer is created by injected gas under pressure to displace free water. PB Energy Storage Services developed the only compressed air energy storage test facility in an aquifer in Pittsfield, Illinois.
Depleted oil or gas reservoirs represent a particular type of porous storage. PB Energy Storage Services engineers can analyze depleted oil and gas zones for natural gas storage potential and design exploratory programs to locate and qualify aquifers for storage. PB is experienced in both developing new storage facilities and enhancing the deliverability of existing facilities.