Vessim is a co-simulation testbed for microgrids*

Vessim lets you model how loads, (renewable) generation, energy storage, and the public grid interact, and test control and dispatch strategies against them, in pure simulation or with real software and hardware in the loop.

*By "microgrid" we mean any local energy system that combines loads, generation, and storage behind a grid connection. Grids can scale from small battery-constrained systems to a GW-scale datacenter campus.

What can I do with Vessim?

Vessim helps you understand and optimize how loads, energy sources, and storage interact. It was originally designed for energy-aware and carbon-aware data centers, but has also been used for other use cases such as battery price arbitrage and demand response for cooling warehouses.

• Control and dispatch strategies: test battery charging/discharging, load-shifting, and price- or carbon-driven dispatch.
• Demand response and power outages: simulate demand response signals or power outages to understand your system's flexibility and test mitigation strategies.
• Microgrid composition: experiment with adding solar panels, wind turbines, or batteries to see how they would affect your energy costs and carbon emissions.
• Energy- and carbon-aware computing: develop applications that adapt their energy consumption to the carbon intensity and price of electricity.

Vessim can simulate multiple distributed microgrids in parallel and easily integrates historical datasets and new simulators. Vessim's software-in-the-loop capabilities let you run real systems against simulated microgrids.

How Vessim Works

Vessim simulates local energy systems, called microgrids, that combine loads (such as computing equipment, cooling, or charging) with energy sources, dispatchable resources like batteries, and a connection to the public grid.

Vessim is built on Mosaik, a general-purpose co-simulation framework. Each hexagon in the diagram is a Mosaik component that can be simulated or run as real software (software-in-the-loop). A microgrid is composed of three kinds of building blocks:

• Actors (red): exogenous consumers and producers whose power is determined by a Signal. Their sum at each step is the microgrid's power delta.
• Dispatchables (gray): controllable resources like batteries or generators. A DispatchPolicy decides how to distribute the power delta across them; any remainder is exchanged with the public grid.
• Controllers (yellow): observe the simulation each step. Built-in loggers record the state, and custom controllers can adjust dispatch parameters or expose the simulation via APIs.

Try it now

Head to Getting Started for a step-by-step walkthrough that builds a complete microgrid in a few lines of code.

You can also explore a finished simulation in your browser: open the Experiment Viewer beta to see the interactive dashboard for the Getting Started run.

Installation

Install the latest release via pip:

pip install vessim

For software-in-the-loop capabilities, install the sil extra:

pip install vessim[sil]

Contact

Please reach out via GitHub Discussions in case of questions.