Vintage confirms commercial CO2 in Nangwarry-1

Vintage Energy Ltd., Adelaide, has flowed carbon dioxide at commercial rates in a production test of its Nangwarry-1 wildcat in former permit PEL 155 in the Otway basin of southeast South Australia.

The company perforated the well across the top of the Pretty Hill formation and produced gas at 10.5-10.8 MMcfd through a 48/64-in. choke at a flowing pressure of 1,415 psi over a 36-hr period.

Analysis during a choked-back extended time showed the well to be highly productive and more than previous commercial flow rates in the region. There was no significant pressure drop in the reservoir after the test flow.

Current recoverable reserve estimates for the carbon dioxide (certified by ERC Equipoise) are 7.8-82.1 bcf with a median best case of 25.1 bcf. The estimates were made before the production test based on a gas column of 98 m thickness.

The recent test indicates a gas column of at least 120 m which could result in an increase in reserves.

Vintage has been granted a retention lease (PRL 249) surrounding the discovery and the company will establish a case for commercial development.