Assessing Firming Requirements to Integrate Renewables is a spreadsheet dispatch model developed by ICF that is used to study intra-hour and intra-day variations in generation and load. The model uses representative single-day renewables (wind, solar) and load shapes, along with conventional generation data, including ramping characteristics in a region to determine the impact of renewables on the ramp rate requirements of the system.
Ten-minute data is used for the load and renewable generation shapes in order to capture the need for fast ramp generation in the system. Using the generation and load input data, such as full-load variable cost, the model creates a merit-order dispatch stack for economic dispatch. The model takes into account operating reserves needed and will observe regulation requirements in assessing the need for fast ramp generation.
Further, the type and amount of curtailment of conventional generation during off-peak periods due to increases in wind generation will also be determined. The model will "dispatch" energy storage as an alternative to fast ramp generation to determine the amount of energy storage that will be needed.
This model is fully customizable with the unique characteristics for each type of generation and region and provides a snapshot of the system requirements in the load following timeframe (10 minutes) with and without various types of intermittent generation.