3D Energi's (ASX:TDO) spud of the Charlemont-1 exploration well offshore Victoria could add A$35 million in net gas value if successful, Euroz Hartleys said in a note on Monday.

The upstream oil explorer recently said the start of drilling in the Otway Basin is "imminent", following the strategic discovery of Essington-1 gas roughly 12 kilometers away within the same license area.

Charlemont-1 is projected to have around 93 billion cubic feet of gas, with a very high 81% chance of success.

Essington-1 has proved the seismic amplitude and Amplitude Versus Offset anomalies as predictive, de-risking the Charlemont-1 well.

Euroz Hartleys currently values the Essington-1 discovery at A$105 million.

The brokerage also noted Charlemont could potentially carry gas in the cluster worth about A$400 million.

Euroz Hartleys maintained its Speculative Buy rating and price target of A$0.34.