EPJ Plus Highlight - 100% renewable energy sources require overcapacity

Germany's greenhouse gas (GHG) emissions from 2002 to 2015 and the political target for 2020 (bars).

To switch electricity supply from nuclear to wind and solar power is not so simple

Germany decided to go nuclear-free by 2022. A CO2-emission-free electricity supply system based on intermittent sources, such as wind and solar - or photovoltaic (PV) - power could replace nuclear power. However, these sources depend on the weather conditions. In a new study published in EPJ Plus, Fritz Wagner from the Max Planck Institute for Plasma Physics in Germany analysed weather conditions using 2010, 2012, 2013 and 2015 data derived from the electricity supply system itself, instead of relying on meteorological data. By scaling existing data up to a 100% supply from intermittent renewable energy sources, the author demonstrates that an average 325 GW wind and PV power are required to meet the 100% renewable energy target. This study shows the complexity of replacing the present primary energy supply with electricity from intermittent renewable sources, which would inevitably need to be supplemented by other forms of CO2-free energy production.

Intermittent sources are, by definition, unsteady. Therefore, a back-up system capable of providing power at a level of 89% of peak load would be needed. This requires creating an oversised power system to produce large amounts of surplus energy. A day storage to handle surplus is ineffective because of the day-night correlation of surplus power in the winter. A seasonal storage system loses its character when transformation losses are considered; indeed, it only contributes to the power supply after periods with excessive surplus production.

The option of an oversized, intermittent renewable-energy-sources system to feed the storage is also ineffective. This is because, in this case, energy can be taken directly from the large intermittent supply, making storage superfluous. In addition, the impact on land use and the transformation of landscape by an unprecedented density of wind convertors and transmission lines needs to be taken into consideration. He also warns of the risk that it will intensify social resistance.

F. Wagner (2017), Surplus from and storage of electricity generated by intermittent sources, Eur. Phys. J. Plus 131: 445, DOI 10.1140/epjp/i2016-16445-3

This was our first experience of publishing with EPJ Web of Conferences. We contacted the publisher in the middle of September, just one month prior to the Conference, but everything went through smoothly. We have had published MNPS Proceedings with different publishers in the past, and would like to tell that the EPJ Web of Conferences team was probably the best, very quick, helpful and interactive. Typically, we were getting responses from EPJ Web of Conferences team within less than an hour and have had help at every production stage.
We are very thankful to Solange Guenot, Web of Conferences Publishing Editor, and Isabelle Houlbert, Web of Conferences Production Editor, for their support. These ladies are top-level professionals, who made a great contribution to the success of this issue. We are fully satisfied with the publication of the Conference Proceedings and are looking forward to further cooperation. The publication was very fast, easy and of high quality. My colleagues and I strongly recommend EPJ Web of Conferences to anyone, who is interested in quick high-quality publication of conference proceedings.

On behalf of the Organizing and Program Committees and Editorial Team of MNPS-2019, Dr. Alexey B. Nadykto, Moscow State Technological University “STANKIN”, Moscow, Russia. EPJ Web of Conferences vol. 224 (2019)

ISSN: 2100-014X (Electronic Edition)

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