Renergen (ASX: RLT) started commercial sales of liquid helium at its Virginia Gas project in South Africa, after resolving cooling delays of its helium iso-containers, according to a Friday filing with the Australian bourse.

In January, the company said it faced delays in cooling a key helium iso-container due to its phase 1 plant at the project operating below nameplate capacity and could not determine when the cooling process of the customer's container will be completed.

To overcome the delay, Renergen has now adopted a workaround using smaller 250 liters to 500 liters Dewar containers, a method it will continue until the plant reaches closer to nameplate capacity, the filing said.

The company has cooled and filled the containers with helium, and the first shipment was collected by a customer Friday, the filing added.

Renergen confirmed that the quality of both its liquefied natural gas and liquid helium now exceeds minimum design specifications.