Remembering Fukushima, Copenhagen 9. March 2013 Opportunities for the future Bent Sørensen Roskilde University

Japan after the Fukushima nuclear accident:  Current scientific assessment of the aftermath  Identifying alternative paths ahead: Renewable energy assessments Energy scenarios for the future Discussions of implementation policy International collaboration

Above: Early fallout reconstruction. All noble gases escaped from reactors 1-3, Xe-133 releases were 3 times higher than for the Chernobyl accident, while Cs-137 releases were about half. Left: Total Cs-137 fallout March 11 to April 20, The behaviour after March 15 indicates that Cs escaped from the spent fuel kept at reactor 4. Source: A. Stohl et al., Atmospheric Chemistry and Physics, 12 (2012) Additional reporting by Brumfiel, Nature 478 (2011) Cs-137 deposition in kBq/m2

Global patterns of accumulated Cs-137 fallout March 11 to April 20, 2011 (unit kBq/m 2 ), based on measurements by the Comprehensive Nuclear-Test-Ban Treaty Organization and atmospheric dispersal modelling using the origin release estimates made by the Japanese Government Nuclear Emergency Response Headquarters during Source: A. Stohl et al., Atmospheric Chemistry and Physics, 12 (2012) Earthquake and tsunami proofing criteria, spent fuel storage permissions: Leaving to many decisions to Power Utility Companies?

Renewable energy resources: wind (Mollweide area-true projection)

Renewable energy resources: solar radiation

Renewable energy resources: primary biomass production A power line between Japan and South Korea would greatly ease renewable source power supply

Sources for renewable energy ressource and practical usage estimates: B. Sørensen: Renewable Energy (Elsevier, 2010) I. Ushiyama et al.: in Wind Engineering, vol. 34 (2010) Japanese scenario work: The bulk of post-Fukushima scenarios consider renewable energy only up to 30% of demand, ignoring energy storage and power exchange, stating that Japan is an island. However, as mentioned power exchange with the continent through Korea is feasible, and Japan already uses pumped hydro storage. With 4-5 times more storage than at present, 100% renewable is possible by 2050, according to study by H. Tsuchiya in Renewable Energy, vol. 48 (2012) : Electricity demand in 2050: 578 TWh or 60% of current, due to declining population and increased energy efficiency. Electricity supply in 2050: 280 TWh from photovoltaic cells 116 TWh from wind turbines 208 TWh from hydro, geothermal, biomass, etc. Energy storage in 2050: 528 GWh (was 113 GWh in 2010), the model uses batteries, but some capacity may be pumped hydro, CAES, etc. Tsuchiya points out that the combination of solar and wind works out better in Japan than in Europe, leading to smaller energy storage requirements.

Several scenario variants can be contemplated, for example according to expectations regarding the relative cost of wind turbines, photovoltaic cells, storage facilities including hydrogen storage and fuel cells, and also according to the structure of the energy sector: Should Japan continue to have many power utility companies with little collaboration (and little power exchange options)? In Europe and several other places, the utility industry has been restructured in a way that encourages power exchange, by separating the production industry from the network responsible organisation, which is specifically not privatised. This is the underlying reason, that expansion of grid connections is being planned all over Europe, as well as between Europe and North Africa with its high solar potential. Will the power market in Asia see a similar internationalisation? The scenario mentioned above discussed only electricity supply. It must of course be supplemented by scenarios for the other energy sectors, but the focus on electricity is warranted, not only after the Fukushima event.

Collaboration between Japanese scientists and energy planners and their counterparts in Denmark and the rest of the world has already increased as a result of the global awareness of the Japanese dilemmas spurred by the accident at Fukushima, as evident from the stream of related papers appearing in the international research journals. It is my hope that this trend will continue, to the benefit of both sides. This presentation can be downloaded from 12 kW PV roof, Kyoto