Accurate and scalable representation of electric vehicles in energy system models: A virtual storage-based aggregation approach.

The growing number of electric vehicles (EVs) will challenge the power system, but EVs may also support system balancing via smart charging. Modeling EVs' system-level impact while respecting computational constraints requires the aggregation of individual profiles. We show that studies typically rely on too few profiles to accurately model EVs' system-level impact and that a naïve aggregation of individual profiles leads to an overestimation of the fleet's flexibility potential. To overcome this problem, we introduce a scalable and accurate aggregation approach based on the idea of modeling deviations from an uncontrolled charging strategy as virtual energy storage. We apply this to a German case study and estimate an average flexibility potential of 6.2 kWh/EV, only 10% of the result of a naïve aggregation. We conclude that our approach allows for a more realistic representation of EVs in energy system models and suggest applying it to other flexible assets.

Assessing the potential of low-carbon technologies in the German energy system.

With the introduction of its energy concept in 2010, the German government set ambitious targets for the country's energy and climate policy. According to this concept, greenhouse gas (GHG) emissions will have to be reduced by 80% by 2050, as compared to 1990 levels, and renewables will have to supply 80% of all electricity needs by the same year. Additionally, Germany has decided to phase out its nuclear energy by 2022. This study investigates the possible components to achieve these targets. The analysis is based on an hourly simulation model EnergyPlan. Three scenarios are developed to investigate the potential development of the German energy supply system until 2050. The results indicate renewable shares of 92% and 81% for scenarios B and A, respectively, by 2050 compared to 69% in the reference scenario. The proposed renewable energy system is even found to involve lower costs than today's energy system (i.e. total annual cost for scenario B is € 260 bn compared to € 293 bn in the reference scenario). The results show that a massive decarbonization of the German energy system until 2050 seems technically and economically feasible, if smart grid costs are disregarded and if this sustainable energy transformation is accompanied by political and genuine public willingness to actually achieve the set goals and take the necessary steps.

Sustainable energy development in Austria until 2020: Insights from applying the integrated model "e3.at"

This paper reports on the Austrian research project "Renewable energy in Austria: Modeling possible development trends until 2020". The project investigated possible economic and ecological effects of a substantially increased use of renewable energy sources in Austria. Together with stakeholders and experts, three different scenarios were defined, specifying possible development trends for renewable energy in Austria. The scenarios were simulated for the period 2006-2020, using the integrated environment-energy-economy model "e3.at". The modeling results indicate that increasing the share of renewable energy sources in total energy use is an important but insufficient step towards achieving a sustainable energy system in Austria. A substantial increase in energy efficiency and a reduction of residential energy consumption also form important cornerstones of a sustainable energy policy.