Planning for a Renewables-First Energy System

To achieve the 2050 climate neutrality goals agreed on at the 21st Conference of the Parties, hosted in Paris by the United Nations in 2015, countries will need to increase their use of variable renewable energy sources (RES) such as wind and solar energy. To balance the grid, flexible resources—including storage, demand response, and load following generation—are increasingly needed to maintain the balance of demand and production on all time horizons in the face of the variable RES load net’s increasing scale, fluctuation speed, transfer capacities, voltage, and power quality.

Grid Operators Should Plan to Tackle Future Flexibility Gaps

To ensure that their grids are prepared for any extreme events that might occur in their territory, transmission and distribution grid operators need to plan to evolve their toolkit with enough time to prevent potential grid instability. The steps in these preparations are as follows:

1. If enough flexible resources are available, identify which problems these resources can help solve. To do this, grid operators need to design new metrics that allow them to measure the problem they are facing (e.g., a cloudy and windless period in the middle of winter or the amount of solar generation lost at sunset on a hot summer day) and then apply these metrics to their long-term adequacy forecasts as part of their routine planning methods.
2. If the metrics show that there might not be enough flexible resources to manage those events, grid operators need to assess whether their current tools (e.g., capacity mechanisms, frequency regulation, and utility programs) can be used effectively to attract new flexible resources into the energy system.
3. If the current toolkit cannot attract the necessary flexible resources to cover the gaps, grid operators should engage regulators in the design of new flexibility focused grid programs or products to procure the additional flexibility needed. 

Although grid operators globally are at different stages in the introduction of variable RES into their grids (and therefore in predicting where flexibility gaps might occur), climate change goals and the economic competitiveness of wind and solar energy resources point toward a future in which more flexibility will be needed. Some grid operators, such as the California Independent System Operator in the US and Elia in Belgium, have started this process. But those grid operators that haven’t should start planning now, first by introducing new metrics to assess flexibility needs and ensuring that any gaps are discovered early enough to develop a strategy to attract new flexible resources.