Natural Gas Storage Facility
Underground storage facility of natural gas in abandoned mine shafts.
In the South African Integrated Resource Plan (IRP), the country has indicated the intent to significantly increase the amount of electric power generation to be sourced from renewable resources, particularly wind and solar. Unfortunately, these two resources are variable and must be backed up with dispatchable power to balance demand with supply.
Dispatchable energy is only used occasionally and when it is used, it must be available in significant volumes. This makes the fuel supply a challenge unless there is a system to provide a buffer storage to provide the large volumes required when needed. For the South African grid, by 2030 it is expected that dispatchable energy must be available to supply up to 10 GW for short durations, but only average less than 200 MW over the year, implying about 2% usage factor.
Abandoned mine shafts can be utilized to provide the required storage volume for natural gas to meet the dispatchable power need.
The concept of mine shaft storage provides an economical concept for natural gas storage with sufficient volume and delivery rate to meet the needs for dispatchable power generation in South Africa, utilizing readily available infrastructure.