The Electricity Markets Investment Suite Agent-based Simulation (EMIS-AS) model is an agent-based model developed at NREL for simulating annual investment and retirement decisions of heterogeneous investors in the electricity sector. EMIS-AS is designed to capture the evolution of the electricity generation portfolio resulting from the interactions of heterogeneous investors under different policy and market designs. EMIS-AS not only allows end-users to customize market products and rules, but also to capture investors' heterogeneous financing parameters, technology preferences, beliefs about the future (forecasts), ability to update those forecasts, and risk preferences under uncertainty.
EMIS-AS is initialized based on the input data detailing the test system, generation units, market design, investors' characteristics and simulation parameters. Additionally, the pre-processing step includes calculation of the weighted average cost of capital (WACC) and adjusted CAPEX for all existing and option projects for each investor. Next, the model selects the specified number of representative days (with hourly resolution) to be used by the investors for price prediction. These representative days and their corresponding weights are determined based on load and renewable generation timeseries using k-medoids clustering.
Subsequently, the simulation commences with successive yearly iterations for the specified simulation horizon. At the start of each simulation year, the investors project future prices and make revenue predictions. The predicted revenues are then used to calculate the expected utility (based on the expected net present value (NPV)) for all projects. Subsequently, the revenue prediction outcomes and expected utility are used to make investment and retirement decisions and for calculation of market bids.
Once all investors have completed their decision-making process, their investment and retirement decisions are announced. The model then updates the build-phases of all projects, which are depicted below.
The projects in the Option phase which get decided to be invested in are sent to the interconnection queue and included in the list of active projects. The projects already in the interconnection queue progress one year further in the queue. The projects which have completed their queue time then enter the construction phase. It is assumed that the investors only have to pay the annual queue costs when the projects are in the queue, but would have to pay the full capital cost once construction commences. The projects which have completed their construction times are included in the set of existing projects. Finally, if any project is to be retired, either due to end-of-life or profitability reasons, is removed from the list of active projects.
The life cycle phase updates are followed by the actual clearing of the modeled electricity markets. The current version of EMIS-AS includes energy, ancillary services, capacity and Renewable Energy Certificates (REC) markets. The investors then update the realized revenues for their projects and also update their beliefs (using Kalman Filters) based on the realized values of the parameters. Finally, the derating factors of variable renewable generation are calculated based on the updated installed capacities using the top-n net-load hour methodology.
While the model's input data for investors and markets can be instantiated directly as
Julia structs, the model provides a CSV-based file import functionality that may be
more convenient. Data organized according to the file structure
described here will be automatically populated into a
corresponding AgentSimulation. The worklow for processing the input data for creating
the AgentSimulation is depicted below.
