Remote island power systems often fail to enjoy the right to secure, clean energy supply. This paper presents a short-term analysis for the electrical system of Rhodes-Halki in South Aegean, with the use of a mixed-integer dispatch module in PLEXOS® Simulation Software. While examining the impact of submarine grid extensions, the results show that following the interconnection of Rhodes' power system, rapid renewable energy deployment is recorded, allowing for electricity exports equal to 220 MWh by 2040. Power generation costs decline by 58.9% for the week recording MAX demand and 54.8% for the week recording MIN demand, compared to the BAU autonomous scenario. The scenario imposing generation restrictions according to directives 2010/75/EU and 2015/2193/EU shows high levels of unserved hourly energy equal to 70%-85%.