Gas storage technology development has been conducted continuously since the evolution of the first storage fields. Better understanding of reservoir
TABLE 8.1 New North American Gas Storage Requirements
Source: Base case from At the Crossroads: Crisis or Opportunity for Natural Gas? Energy and Environmental Analysis Inc. With permission. |
responses to gas storage conditions, mechanical issues with wellbores, flow capacity, and formation damage have all been investigated. Gas storage presents some unique technology challenges as compared to other exploration and production operations. Included is the need to recharge storage fields on a regular basis. Recharging exposes the wellhead and wellbore environment to maximum operation pressures annually but requires all equipment to be maintained for those conditions. In standard oil and gas operations, the maximum pressure is realized during early production and declines thereafter.
Another area of unique challenge arises from aquifer gas storage fields that require overpressure conditions to inject gas into the reservoir. The operation needs a caprock to prevent gas movement from the reservoir during overpressure conditions. Typical oil and gas fields have proven the value of the caprock technique by the oil and gas accumulations contained. This condition does not exist for aquifer fields.
The U. S. Department of Energy conducted an industry workshop to assess technology needs for near – and long-term gas storage. Five major topic areas were identified and research needs within each category identified and prioritized (Table 8.2).