Indoor Climate and Energy Tools

Welcome to the collection of freely available Indoor Climate and Energy Tools developed by the Institute for Energy Efficient Buildings and Indoor Climate at RWTH Aachen University. You are cordially invited to use the tools. Please do not hesitate to contact us for your feedback and contributions.


Under AHULife, the Institute for Energy Efficient Buildings and Indoor Climate provides a tool for calculating the energy demand and life cycle costs of air handling units. The energy demand is simulated based on hourly resolved weather data and internal loads. The user can choose between various configuration options.


AixLib is an open-source Modelica model library for building performance simulations. It contains Modelica models for building envelope and HVAC equipment such as boiler, radiator, heat pump and CHP. Emerging out of the Institute’s needs in research and teaching, AixLib contains models of different level-of-detail. The library extends the collaboratively developed Annex60 library, which focuses on basic model.

CityGML ADE Energy

This extension of the CityGML standard for urban information modeling as an Application Domain Extension (ADE) defines a data model for urban energy analyses, aiming to be a reference exchange data format between different urban modelling tools and databases. It has been developed by an international consortium of urban energy simulation experts.


TEASER (Tool for Energy Analysis and Simulation for Efficient Retrofit) allows fast generation of individual archetype buildings with low input requirements and the export of dynamic building simulation models for the AixLib and other open-source Modelica libraries.


uesgraphs is a Python package to describe Urban Energy Systems and manage their data in a Python graph structure. uesgraphs can be used as a foundation to analyze energy network structures, evaluate district energy systems or generate simulation models.


NOODEL (33 NOde cOmfort moDEL) is a multi-node comfort model written in Modelica for predicting human comfort in various indoor situations. It consists of a thermophysiological body model and a psychological model.

BUDO Schema

The BUDO Schema (Buildings Unified Data point naming schema for Operation management) structures the designations of data points in the building in such a way that an operator and a machine can interpret them. This structured data can be used for error analysis, optimization or measure development with the help of artificial intelligence within a building energy system.


EHDO is a webtool supporting the planning process of complex energy supply systems. The tool has been developed by Institute for Energy Efficient Buildings and Indoor Climate at RWTH Aachen University for academic teaching. EHDO supports the planning of future energy supply systems and to estimate the potential of renewable energies and future energy carriers like hydrogen. A wide range of innovative technologies like fuel cell, electrolyzer, hydrogen storage, photovoltaic and wind turbines as well as biomass and waste-to-energy technologies can be considered in the tool.


RisiCo is a tool that can be used to determine the relative risk of infection by aerosol-borne viruses in indoor spaces as a function of exclusively technical parameters and characteristics of the persons present for two reference environments. The reference environment corresponds to a mechanically ventilated classroom according to the state of the art, which has a comparatively low absolute risk of infection according to the current state of knowledge.


AixOCAT is an open source software library for the implementation of control algorithms in building automation systems and test benches. This library features support for different software tools that can be used for the implementation of control algorithms as well as support for various commonly used communication/signal transmission interfaces.

This website uses Cookies. More information. Press "I accept" to accept Cookies. I accept