The drilling program is intended to target the Tulip Upper Isongo and Tulip Massive Isongo zones.
The company estimates the Block Z, which is located to the north of Bioko Island and south of the Marathon Oil-operated Alba field, to hold gas reserves of more than 3.6 trillion cubic feet (tcf).
Based on a 600km2 3D seismic campaign completed in 2014, the company identified the Tulip, Daisy, Buttercup and Sunflower prospects.
The block also comprises the Gardenia discovery, which was identified in 2004.
RoyalGate Energy president Frank Ene said: "This is the continuation of what we see as a long term partnership with Equatorial Guinea and we see a lot of development potential for Block Z.
"We are bullish about the prospectivity of this block and our other assets in Equatorial Guinea."
The Z-1 well is planned to be drilled close to the location of previous offset wells, which provided initial geological and geophysical data, the company added.
In April 2013, RoyalGate Energy signed production sharing agreements with the Ministry of Mines, Industry and Energy for Block Y and Block Z.
RoyalGate Energy, in partnership with GEPetrol, is undertaking explore program in the two blocks.
