Osamu Akashi

A low-carbon society: global visions, pathways, and challenges

The feasibility of two low-carbon society (LCS) scenarios, one with and one without nuclear power and carbon capture and storage (CCS), is evaluated using the AIM/Enduse[Global] model. Both scenarios suggest that achieving a 50% emissions reduction target (relative to 1990 levels) by 2050 is technically feasible if locally suited technologies are introduced and the relevant policies, including necessary financial transfers, are appropriately implemented. In the scenario that includes nuclear and CCS options, it will be vital to consider the risks and acceptance of these technologies. In the scenario without these technologies, the challenge will be how to reduce energy service demand. In both scenarios, the estimated investment costs will be higher in non-Annex I countries than in Annex I countries. Finally, the enhancement of capacity building to support the deployment of locally suited technologies will be central to achieving an LCS. Policy relevance Policies to reduce GHG emissions up to 2050 are critical if the long-term target of stabilizing the climate is to be achieved. From a policy perspective, the cost and social acceptability of the policy used to reduce emissions are two of the key factors in determining the optimal pathways to achieve this. However, the nuclear accident at Fukushima highlighted the risk of depending on large-scale technologies for the provision of energy and has led to a backlash against the use of nuclear technology. It is found that if nuclear and CCS are used it will be technically feasible to halve GHG emissions by 2050, although very costly. However, although the cost of halving emissions will be about the same if neither nuclear nor CCS is used, a 50% reduction in emissions reduction will not be achievable unless the demand for energy service is substantially reduced.

Energy Efficiency and Conservation Strategies in Japan and Their Implications in China’s Future Energy Development

This chapter describes energy efficiency and conservation strategies in Japan by showing the historical trends of energy consumption and energy efficiency improvements. The Japanese experience demonstrates that efforts to solve environmental problems have served to improve energy efficiency in various fields. A mitigation scenario to halve global GHG emissions by 2050 is presented, and a comparison is done between effective technologies in Japan and China to achieve the target. Although the model analysis shows that a certain set of technologies can improve energy efficiency by 3 % per year and CO2 intensity with respect to GDP by 3.5 % per year in China by 2050, implementation of the scenario depends on a number of more specific conditions: rates of installation must be achievable; sufficient finance must be mobilised; and barriers to the adoption of low carbon technologies must be overcome. With China’s progress in energy efficiency improvement, there are greater opportunities for the country to take further steps in this area so as to contribute not only to economic development and energy security, but also to global climate stabilisation.