Based on existing power systems, the IEA identifies four phases in VRE integration, each with specific characteristics and operational priorities. In the first phase, wind and solar have no noticeable impact on the system, and the priority is to communicate clearly where and when solar and wind projects can connect, and what technical requirements these plants must comply with. In a second phase, the focus shifts to managing first instances of grid congestion, and to incorporate forecasts of VRE generation in the scheduling and dispatch of other generators. In the last two phases, wind and solar start to affect the overall grid and other generators.

As the share of VRE grows, the challenges that power systems face will relate both to system flexibility – relating to supply and demand in the face of higher uncertainty and variability – and system stability – the ability of the of power systems to withstand disturbances on a very short time scale.

Source: Getting Wind and Solar onto the Grid

16 March 2017