E3.at is a macroeconomic, multi-sector input-output model. It depicts the Austrian economy both as a whole and broken down by industrial sector. The model also takes into account regional developments at the federal state level. The model incorporates both supply and demand-side of the economy for all industrial sectors and goods categories. It depicts the circular flow of income in full and differentiates between different economic sectors (e.g. corporations, the government, private households).

The economic model is coupled with the energy and environment modules. These three modules give the Austrian model its name: e3.at.

The energy module comprises energy supply, energy conversion and energy demand from a range of consumers (e.g. the manufacturing sector, households) for various fossil and renewable energy sources.

In Austria, domestic users and the transport sector are both significant energy consumers. To improve modelling of heating and vehicle fuel consumption, the model also incorporates characteristics of the housing stock and car inventories affecting energy consumption.

The environment module depicts material consumption (biomass, minerals, fossil fuels) and CO2 emissions.

The data used by the model is derived from publicly available data sources (including Statistik Austria). Interrelationships are modelled by identities (e.g. in an input-output context) or validated empirically.

The integration of all modules into a single model has the advantage that direct and indirect effects of policy measures and instruments can be quantified for all ‘E’s. The modelling approach allows for identifying winners and losers and reveals any rebound effects. It also enables to calculate macroeconomic effects and enables conclusions to be drawn on social balance and ecological benefit.