This paper presents a new power sector module, called EUTGRID, which is coupled with the long-term energy model POLES to deliver a suitable framework for considering grid aspects in energy modelling allowing for more distinct analysis of energy technology development and energy policy. It includes a mechanism of investment in transmission grids based on nodal prices together with a DC-load flow and a more detailed description of the European transmission grid. The methodology goes beyond "conventional" energy systems modelling, where the electricity grid is usually represented as a copper plate. The results show that within a climate policy scenario, the grid investment needs reach 454b$ for 2010-2080 as regions with high share of VREs require new interconnections. The role of the transmission grid in reducing variable system costs and VREs curtailment is also assessed. Delaying the investments may result in non-distributed energy and the need of more back-up carbon technologies. (C) 2020 Elsevier B.V. All rights reserved.

Previous works proposed a tool coupling models of a prospective outlook on long-term energy systems and a transmission grid investment and dispatch, focusing on the representation of the European transmission grid and its development on the horizon 2050-2100. In this paper, this prospective tool is further improved with the capacity to compute voltage as well as active and reactive power flows at the level of the distribution grid. This added capacity allows analyzing various issues related to the integration of variable energy resources in three representative real medium voltage distribution grids (urban, rural and semi-urban). Technical flexibility solutions such as on-load tap changers, variable energy resources curtailment and storage technologies are modeled and compared to reinforcement. A cost comparison between these flexibility solutions is also carried out. Finally, the new version of the tool is used to evaluate the CO2-eq emissions linked to the development of the European power system infrastructure, with flexibility solutions, up to the year 2050 (both high voltage alternative and direct current lines reinforcement being considered) under a 2 degrees C climate energy policy scenario. Results show that it exists various options for the development of the European grid infrastructure, which are clearly sensitive to the level of accuracy in the representation of the physical infrastructures and their technical limitations. Being able to represent the distribution grid, in addition to the transmission one, has a noticeable impact on the prospective outlook of the European power systems both in terms of infrastructure reinforcement and estimation of the needs of flexibility solutions.

This paper reports the recent work carried out to engage both the environmental impact and the economic indicators on the prioritisation of dispatchable technologies in the European energy mix up to 2050. Those two contradictory indicators are incorporated in a multi-criteria optimisation leading to iterations of two scenario: business as usual and 2 °C climate policy. The results present the evolution of the climate change emission versus the operational costs of the power system up to 2050. The yearly electricity mix evaluations allow assessing the long-term development of the European energy system, where a focus is done on variable renewable energy production. It is shown that policy-only solutions, associated with a traditional cost-oriented optimisation, have a limited impact on helping the power sector to reach emission levels targets. Integrating the objective of reducing emissions to the management of power plants would reduce the absolute and cumulative carbon dioxide equivalent emissions. The counterpart is that the system electricity price tends to increase faster thus implying increased social costs.

L'intégration massive des énergies renouvelables variables (EnRV) provoque d'importants changements dans le système électrique. Auparavant développé de manière vertical et centralisé, le système était robuste et fiable. Cependant, la production des EnRV est intermittente et peu prévisible. Ainsi, le système doit être plus flexible grâce à de nouvelles options telles que la maîtrise de la demande, le stockage ou l'effacement de la production EnRV. Cependant, le potentiel des EnRV est réparti inégalement en Europe et avec d'importants taux de pénétration d'EnRV, les échanges d'électricité entre les régions vont augmenter provoquant des congestions dans le réseau. Ainsi, les options de flexibilité ne pourront peut-être pas réduire ces congestions. Pour analyser ces effets, le travail mené dans cette thèse utilise le modèle de prospective long terme POLES (Prospective Outlook on Long-term Energy Systems) couplé avec le nouveau module du secteur électrique EUTGRID (EUropean – Transmission Grid Investment and Dispatch). Ce module inclut une représentation détaillée du réseau de transport européen d'électricité avec un calcul des flux plus réaliste. De plus, les renforcements sont déterminés suivant les coûts de congestion de chaque ligne. Ce nouveau couplage permet d'avoir une évolution dynamique du réseau de transport. Le rôle du réseau de transport est ensuite analysé et comparé avec les autres options de flexibilité. Les investissements dans le réseau augmentent ainsi fortement avec d'importants taux de pénétration des EnRV alors que les options de flexibilité ne peuvent pas intégralement remplacer le réseau. Finalement, un travail exploratoire est mené avec l'introduction de réseaux de distribution génériques (urbain, semi-urbain and rural) dans EUTGRID. Les résultats montrent que les renforcements sont légèrement décalés avec une augmentation de l'utilisation des technologies de back-up (i.e. centrales à gaz) ce qui augmente les émissions totales.

Most prospective studies of the European power system rely on least-cost evaluations. This study assessed the influence of environmental impact indicators on prioritisation of ‘dispatchable’ technologies in the European energy mix up to 2050, compared with a purely cost-optimal system based on carbon tax incentives, without suppressing economic growth considerations. A model that combined the Prospective Outlook for Long-term Energy Systems model (POLES) and the European and Transmission Grid Investment and Dispatch model (EUTGRID)was used in the analysis. Combined current and prospective life cycle assessment (LCA) methodologies were added to the EUTGRID model to include environmental considerations in the decision-making process. Shifting from an economic to an environmental merit order in prioritisation increased the share of renewables by 2.65% (with variations between countries) and decreased overall emissions by 9.00%. This involved a change in grid infrastructure. Investments were found to be more important when optimisation was based on an environmental criterion on new high-voltage AC power lines, which resulted in a 1.50% increase in the overall cost of the power system. Finally, considering an environmental, instead of an economic, merit order allowed decarbonisation to be achieved slightly faster, resulting in lower cumulative greenhouse gas emissions to the atmosphere.

This paper focuses on the implementation of two main solutions (reinforcement and energy storage systems) in a low-voltage (LV) network with an important photovoltaic (PV) integration. The electrical network considered is a rural low voltage network which includes 20 clients and its PVs. The study is carried over 30 years with constant consumption and a rate of installation of PVs set to 3%. The model uses a Monte Carlo approach to model consumption and PV production. It can determine a planning of reinforcement and also the power of batteries needed to prevent overvoltage. The results indicate that energy storage systems have more benefits than reinforcing cables in this particular situation. Sensitivity analysis have been performed on different parameters which show the different conditions where reinforcement can compete with energy storage systems.

This paper compares the performance of smart charging and dumb charging applied to Electric Vehicles (EVs) by implementing a simulation model. The model was developed based on the trend of current electric vehicle adoption in Norway. The electrical network system considered includes wind turbine to supply electric power to a group of 38 households. The assumed scenario is that the households own 31 EVs, which is equivalent to 60% of current EV adoption in Norway. The network is an almost stand-alone network as it mainly relies on wind power and if needed, power is purchased from the Nordic spot market. The obtained results indicate that the smart charging has several advantages if it is used with the support of energy storage: it prevents the event of peaks in electricity demand, it increases the use of wind power and it reduces the dependency from the spot market.