Apart from the cost benefits, there are many other advantages to choosing biogas membrane storage technology over the conventional steel tank storage in South Africa.

Double Membrane Gas Storage (DMGS) vs Steel Tank Storage

  • DMGS is more cost effective in terms of capital investment. This is mainly based on the price of steel and overall costs of membrane technology can be up to 10 times cheaper than steel.
  • A DMGS requires a very short installation time. Typical installation lead time is from 1 to 5 days.


Membrane technology of a DMGS is totally resistant to the effects of biogas and its components whilst steel parts can be effected by corrosion; meaning:

  • No special periodical coating procedures are necessary and maintenance costs can be kept to a minimum.
  • The DMGS has an average lifetime of approximately 10-15 years and boasts little to no maintenance efforts.
  • Any checks or maintenance can be done while the DMGS is in operation.
  • No interruption of the process and no flaring of biogas is necessary.


  • A DMGS can be easily dismantled.
  • Quick membrane exchanges are possible when increasing capacity or after end of lifespan. Further protection from tropical storms is possible with minimum efforts.
  • Due to its low mass, a DMGS is quite resistant to earthquakes.
  • Double membrane gas storage supplied by Renew complies with the highest safety standards worldwide. They can cope with high wind and snow loads.


  • Accurate filling level measurement by ultrasonic measurement provides precise information about the stored amount of biogas in the DMGS.
  • When connected to the PLC, the measurement signal allows for exact regulation of CHP units, boilers or flares.
  • A DMGS provides constant gas flow with its supporting air-blower at constant pressure, granting smooth and uninterrupted operation without having to “suck” gas out of the vessel.