Exploring a 2030 nearly 100% renewable Spanish electricity system from a capacity-mix adequacy perspective

Nowadays, the increase in gas prices in Europe is fostering the penetration of renewable generation in electricity systems and pressing countries to accelerate the energy transition. It is then arguable whether goals on decarbonizing the system by 2030 set by National Energy and Climate Plans might be revisited towards more ambitious ones. This study explores the viability from a capacity-mix adequacy perspective of meeting a 2030 nearly 100% renewable Spanish electricity system without compromising the security of supply and economic affordability. The study builds scenarios with a progressively higher share of renewable energy production using a generation/storage expansion planning model. Renewable energy production shares, CO2 emissions, generation technologies, investment, and operation costs are monitored and discussed. The paper shows the viability of reaching renewable energy production shares as high as 95% at a reasonable cost and also how the cost significantly increases when trying to reach higher percentage values.