Material flow analysis (MFA) is a method for analyzing the relationship between economies and environmental issues. MFA
is usually on the basis of weight unit. However, materials have a strong relationship with energy. Therefore, we intend to
improve MFA by introducing the viewpoint of energy. In this study we define a concept of virtual energy of each material.
Using the concept of the virtual energy, we evaluate the virtual energy intensity of fuels, major materials (such as steel,
aluminum, copper, plastics, rubber, and glass), and automobiles that represent complicated goods. We calculate the virtual
energy intensity of not only new goods but also wastes and used goods such as steel scrap and used cars. We also evaluated
the virtual energy flow of the major goods including the wastes and the used goods between Japan and abroad. We consider
the concept of the virtual energy is a powerful tool for energy flow analysis including wastes and used goods.
In Germany, “nuclear energy phase-out” policy was adopted in 20 in order to promote renewable energy power generation.
Until 207, Germany’s renewablenergy power generation has increased rapidly while its nuclear power generation has
somewhat decreased. In that sense, nuclear energy phase-out has ben sucesful. However, Germany’s power suply
structure in which fossil fuel thermal power generation centering on coal thermal has major share has hardly changed.
Furthermore, the fossil electric power generation has increased as the entire electricity demand in Germany has expanded. It
has brought the increased emission of carbon dioxide which is seen as the major cause of the global warming. On the other
hand, the electricity price in Germany has risen not only in the absolute value but also in the relative position in international
comparison. The high electricity price may be one of the heavy burdens to the German economy. Renewable energy and
nuclear power should not be seen as rivals. Both energies can be promoted simultaneously.
Urban policies towards compact cities and modal shift are considered as important mitigation measures for global warming.
They are estimated to have a substantial impact on CO2 emission reduction from urban activities, which is derived by the
change of behavior of urban entities like households and firms. This means the urban mitigation policies would affect on the
level of happiness or quality of life of dwellers as well. The impact of urban policies, therefore, should be assessed regarding
both CO2 emission and sustainability.
This study presents the applicability of a land use-transport model for the urban mitigation policy assessment. First, we
develop a model in which the behavior of urban entities like location choice/ daily trips of households and firms are explicitly
formulated. Second, this model is applied to two urban policies, road pricing and land use control, to assess the long term
impact on CO2 emission and sustainability. As a result, the developed model is verified, under assumed conditions, to have
capacity for the assessment of urban policies regarding CO2 emission and sustainability consistently.
We estimate potential CO2 emission reduction in the freight sector by optimizing the physical distribution for the following
two cases: the modal shift in the transportation and the change of the industrial structure to "local production for local
consumption". The modal shift in the transportation can reduce CO2 emissions to 54 % compared with the present. The
decrease in the transport distance can reduce CO2 emissions to 58% compared with the present. While minimizing transport
cost shows the same trend, minimizing transport time does not contribute CO2 emission reduction. This paper also shows the
relationship between physical distribution and industrial production by the conception of "derived physical distribution". The
derived physical distribution is clearly different from that of present physical distribution when optimizing CO2 emissions in
the case that transport distance can be changed. Combining the optimization analysis and the input-output analysis in the
physical distribution, the optimized physical distribution can be depicted by visualizing industrial activities.
In recent years, as a supplement for conventional large-scale power generation system, distributed energy system has got
much comprehensive attention. In this study, in order to realize a low-carbon society, a distributed energy system has been
promoted by taking into consideration the integration of combined heat and power (CHP), biomass energy and photovoltaic
technologies, for an urban area in China. As an illustrative example, an investigation has been conducted of feasible
distributed energy system for civilian facilities in a model area of Huzhou city, China. By using a design and evaluation
model, five scenarios with different technology combinations have been analyzed for optimal adoption and operation.
According to the simulation results, although having reasonable environmental merits, it is hard to diffuse the distributed
energy system, especially some renewable resources, in the model area from the economic point of view. Currently, the most
feasible distributed generation technology is natural gas CHP system, which leads to a cost reduction ratio of only 0.7%.
This paper evaluates policy measures implemented for diffusing photovoltaics and solar thermal system in terms of the
contribution to CO2 emission reduction from the residential sector. We investigated the preference of consumers to these
technologies as well as the influence of the attributes of these technologies, such as installation cost, energy price, energy
efficiency and perception), on the consumer’s choice. Taking the influence into account, we developed a model estimating the
diffusion of these technologies into the residential sector of Japan until 2025 and the resultant CO2 emission reduction. We
found that policy measures for diffusion of photovoltaics that reduces initial cost (e.g. subsidy program) is more cost effective
for reducing CO2 emission compared with those reducing operation expenditure of users (e.g. feed in tariff program), while
the perception to solar thermal system must be improved so that the technology will deliver a considerable amount of
reduction of CO2 emission.