The current energy crisis in Europe, largely generated by the considerable reduction in Russian natural gas flows, forces the European authorities to accelerate the transition to renewable energy sources, although changing the structure of the energy mix too quickly can generate accentuated imbalances, which translate into major costs of balancing and in higher bills for end consumers. The study involves the analysis of the historical volatility of energy production from renewable sources in Romania (hydropower, wind energy, photovoltaic energy, and that from biomass), by using ARCH/GARCH models through EVIEWS 12 software, and its contribution to national consumption, in the period January 1st, 2020 - September 1st, 2022, using actualized at 10-minutes intervals. The research results highlight the instability of energy production from renewable sources and the need to identify solutions to reduce balancing costs, so that green energy can represent a cost-effective solution for ensuring energy independence and combating pollution, both from a technical and economic point of view.