and importers, becoming fifth in primary energy consumption, third in both petroleum imports and consumption, and first in liquified natural gas (LNG) imports.
In addition, petroleum holds the largest fraction in the primary energy supply mix
(44%), followed by coal (27%) and natural gas (22%), and the ratio of fossil fuels in
total energy supply amounts to 93% in 2013 [1]. Moreover, the Japanese energy
self-sufficiency ratio shows a considerably lower level, since the energy supply in
Japan depends on imports of almost all fossil fuels; the Japanese energy
self-sufficiency ratio is only 7% in 2013 [1], which exhibits a level below that in
other developed countries. In addition, Japan is heavily dependent on the Middle
East for about 80% of its domestic crude oil supply. Thus, nuclear power has
traditionally played an essential role to ensure domestic energy supply in Japan
where the situation of energy balance is considerably vulnerable as explained.
However, the impact of Fukushima nuclear accident, caused by Great East Japan
Earthquake in Japan, is quite influential on the Japanese energy mix and
socio-economy, and has caused intensive discussion for rethinking energy policy
thereafter which strongly supported nuclear energy. Elaborate political and technical effort has been dedicated to replace the loss of nuclear power supply, an
important base-load technology contributing to energy security and environmental
sustainability before the Fukushima. Actually, after the Fukushima accident,
alternative energy sources compensating nuclear have shown a dramatic increase
such as natural gas, petroleum and solar photovoltaic (PV) as well as electricity
conservation. Therefore, the severe nuclear accident is considered to be one of
driving force which might change the pathway of the country’s energy mix, and the
Fukushima can be understood as the tipping point for the country to pursue energy,
environmental and nuclear policy adjusting into the socio-economic circumstance
after the Fukushima.
Until now, a lot of academic effort has been dedicated to the development of
energy system model which allows us to yield long-term energy scenario in a
consistent way and to analyze the effectiveness of energy and environmental
political instrument such as carbon tax, regulation or subsidization. However, the
majority of existing analysis does not explicitly assess the impact of disruptive
nuclear accident and its successive shutdown on the long-term pathway of energy
portfolio, although the accident is actually observed to dramatically alter the situation of energy balance in Japan.
The objective of this chapter is to overview the transition of energy supply and
demand in Japan after the Fukushima, and, based on that, to discuss the possibility
of considering nuclear accident as contingency risk in energy modeling analysis by
applying the methodology of risk analysis such as stochastic dynamic programming. The chapter is organized as follows: Sect. 2 describes the energy balance
situation in Japan before and after the Fukushima accident; Sect. 3 discusses the
possible methodology to consider a nuclear accident in energy model and Sect. 4
depicts the concluding remark.
98
R. Komiyama
In addition, petroleum holds the largest fraction in the primary energy supply mix
(44%), followed by coal (27%) and natural gas (22%), and the ratio of fossil fuels in
total energy supply amounts to 93% in 2013 [1]. Moreover, the Japanese energy
self-sufficiency ratio shows a considerably lower level, since the energy supply in
Japan depends on imports of almost all fossil fuels; the Japanese energy
self-sufficiency ratio is only 7% in 2013 [1], which exhibits a level below that in
other developed countries. In addition, Japan is heavily dependent on the Middle
East for about 80% of its domestic crude oil supply. Thus, nuclear power has
traditionally played an essential role to ensure domestic energy supply in Japan
where the situation of energy balance is considerably vulnerable as explained.
However, the impact of Fukushima nuclear accident, caused by Great East Japan
Earthquake in Japan, is quite influential on the Japanese energy mix and
socio-economy, and has caused intensive discussion for rethinking energy policy
thereafter which strongly supported nuclear energy. Elaborate political and technical effort has been dedicated to replace the loss of nuclear power supply, an
important base-load technology contributing to energy security and environmental
sustainability before the Fukushima. Actually, after the Fukushima accident,
alternative energy sources compensating nuclear have shown a dramatic increase
such as natural gas, petroleum and solar photovoltaic (PV) as well as electricity
conservation. Therefore, the severe nuclear accident is considered to be one of
driving force which might change the pathway of the country’s energy mix, and the
Fukushima can be understood as the tipping point for the country to pursue energy,
environmental and nuclear policy adjusting into the socio-economic circumstance
after the Fukushima.
Until now, a lot of academic effort has been dedicated to the development of
energy system model which allows us to yield long-term energy scenario in a
consistent way and to analyze the effectiveness of energy and environmental
political instrument such as carbon tax, regulation or subsidization. However, the
majority of existing analysis does not explicitly assess the impact of disruptive
nuclear accident and its successive shutdown on the long-term pathway of energy
portfolio, although the accident is actually observed to dramatically alter the situation of energy balance in Japan.
The objective of this chapter is to overview the transition of energy supply and
demand in Japan after the Fukushima, and, based on that, to discuss the possibility
of considering nuclear accident as contingency risk in energy modeling analysis by
applying the methodology of risk analysis such as stochastic dynamic programming. The chapter is organized as follows: Sect. 2 describes the energy balance
situation in Japan before and after the Fukushima accident; Sect. 3 discusses the
possible methodology to consider a nuclear accident in energy model and Sect. 4
depicts the concluding remark.
98
R. Komiyama