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Your partner for energy system modelling:

Bernadette Riesner

Managing Advisor


Austria's sustainable energy system |
100% decarbonised

The optimised energy system ONE100 is a starting point for a rational, fact-based dialogue on which energy system Austria should aim at in the long-term, as a guideline for a sustainable and efficient energy transition.

Client Profile

  • AGGM Austrian Gas Grid Management
  • Austrian Power Grid AG
  • Energienetze Steiermark GmbH
  • Gas Connect Austria GmbH
  • Netz Burgenland GmbH
  • Netz Niederösterreich GmbH
  • Netz Oberösterreich GmbH
  • Salzburg Netz GmbH
  • TIGAS Erdgas Tirol GmbH
  • Trans Austria Gasleitung GmbH
  • Vorarlberger Energienetze GmbH
  • Wiener Netze GmbH

How to design Austria's future energy system to achieve decarbonisation at the lowest possible cost to society? How can Austria's security of supply be safeguarded – despite the highly fluctuating nature of the renewable energy sources like wind, solar and hydro power?

To answer these questions in open and unbiased manner, 12 Austrian energy companies launched the project ONE100.



The energy transition is the largest project in the country's history. In the coming decades, the energy transition will require investments in the triple-digit billion euro range – in the energy industry and by millions of Austrian end consumers.

A clear and broadly supported vision of the future Austrian energy system is therefore needed in order to coherently guide the numerous future investment decisions of all stakeholders.

This required vision for Austria's future decarbonised energy system must answer the essential technological questions along the entire value chain of the energy industry and among energy consumers in a concrete and tangible way and be supported by all relevant stakeholders.

Such a broadly supported target design for Austria's future energy system requires an intensive social dialogue. And every dialogue needs a starting point.

The ONE100 intends to provide such a starting point.



To calculate the optimised energy system ONE100 WECOM's energy system planning tool WALERIE was used. WALERIE is the market-leading, fully data-driven system for regionalised optimal planning of entire energy systems.

  • The determination optimised energy systems with WALERIE is carried out entirely by means of mathematical optimisation (and not via forecasts of the use or non-use of certain technologies).
  • The optimisation aims at identifying the energy system with the lowest annual cost to Austrian society among all energy systems that are feasible, decarbonised and safeguard security of supply.
  • The determination of the optimised energy system with WALERIE is carried out entirely by means of mathematical optimisation (and not via forecasts of the use or non-use of certain technologies).
  • The optimisation aims to identify the energy system with the lowest sustainable annual costs for the Austrian economy among all feasible decarbonised and secure supply energy systems for Austria.



  • The optimised decarbonised energy system ONE100 incurs almost the same societal costs as Austria’s current energy system. Energy system costs increase only about +1% compared to 2019. The optimal design of the ONE100 thus ensures an affordable decarbonised energy system for Austria.
  • In the optimised energy system ONE100, a broad mix of technologies and energy carriers contributes to cost-efficient decarbonisation. Along the energy value chain – from the provision of primary energy to final consumption – numerous technologies using green power, green gases, green district heating and biomass enable a least-cost energy system design.
  • Fossil primary energy sources like oil, natural gas and coal, which still dominate today (around two-thirds of current primary energy), disappear completely in the ONE100 and are replaced by substantial energy savings (minus one-third energy consumption) and by CO2-neutral energy sources.
  • In ONE100, CO2-neutral primary energy is supplied by a variety of sources, most of which (96%) are domestic: most importantly renewable power from hydro, wind and solar energy, followed by biomass.
  • Before primary energy is used by end users, it is – economically optimally – to a significant extent converted to another energy carrier or stored.
  • E.g. district heat becomes an increasingly important energy carrier which is generated by a diverse asset park with high source flexibility and substantial heat storage capacities.
  • In the economically optimised energy system ONE100, networks for power, methane, hydrogen and district heat are required to a significant extent, e.g. to connect decentrally distributed energy production to storage locations and final consumers.


  • 120

    technologies modelled

  • > 4 m

    optimisation decisions taken

  • > 240

    external studies for parameterisation

  • 12

    project partners

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