Phases of Variable Renewable Energy Integration

This table shows the four general phases of variable renewable energy integration with notes on phases five and six, describing effects on the grid and potential responses. The ability of a grid to integrate variable renewable energy (VRE) will depend on its technical specifications, regulatory practices, operational and institutional practices, and other market factors--so there is no specific percentage of renewable energy for each phase. However, this chart shows a range of example countries at each phase and their specific statistics.

No country has yet reached Phase 5 or 6 as of early 2022, but it is possible that in coming years some countries could reach points at which VRE begins to provide temporary surplus of electricity and/or when VRE power production is disrupted that the system may suffer through periods of electricity deficit. This could require the use of hydrogen or other inter-seasonal storage approaches on a larger scale.
Source: Data on specific country examples drawn from International Energy Agency. Analysis on the phases of VRE integration drawn from the IEA, National Renewable Energy Laboratory, Embed