To address the inherent challenges of intermittent renewable energy generation, this paper proposes a comprehensive energy optimization strategy that integrates coordinated wind–solar power dispatch with strategic battery storage capacity allocation. This study investigates the optimization of wind-solar-gas-storage integrated energy systems (IES) under the dual-market mechanisms of carbon emission trading (CET) and green certificate trading (GCT). A unified analytical framework is developed to examine the techno-economic and environmental. Solar photovoltaics (PV) and wind power have been growing at an accelerated pace, more than doubling in installed capacity and nearly doubling their share of global electricity generation from 2018 to 2023. Through the development of a linear programming. Wind and solar power plants, like all new generation facilities, will need to be integrated into the electrical power system. This fact sheet addresses concerns about how power system adequacy, security, efficiency, and the ability to balance the generation (supply) and consumption (demand) are. The integration of VRE can be categorised into a framework made of six different phases, which can be used to prioritise different measures to support system flexibility, identify relevant challenges and implement appropriate measures to support the system integration of VRE.