Distributed energy system (DES) was highly positioned in the energy supply and demand perspective issued in 2005 by METI and it is expected to be introduced more than 20% of nationwide generating capacity. This is mainly because introduction of DES is expected to reduce primary energy consumption, CO₂ emission, to increase energy supply reliability, to develop employment and local industries and so on. Even though several incentives have been introduced in Japan to penetrate DES such as CHP, the definition of CHP is not clear and there have been a lot of discussions about its energy saving capability. The definition of CHP was stipulated in the State in 1978. In Europe, most countries had their own definition and they are going to be unified by EU to penetrate CHP for global warming mitigation. This paper introduces the latest policies to disseminate DES and definitions of cogeneration in the world and discusses their applicability of the defini-tion to Japan.

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A new academic discipline, Energiology, or Energetica, has been proposed as an trans-disciplinary ap-proach to energy issues, which harmonizes natural, social and cultural sciences. In this paper, the various discussions so far on Energiology are analyzed firstly to identify their common directions of arguments. Based on this analysis, the framework is presented for further examinations in order to form a concept of Energiology. Also, the meaning of establishing a new ‘discipline’, the implication of trans-disciplinary movements, and the significance of problem-solving approach are discussed to clarify the basic elements for the concept of Energiology. Finally, based on these preparatory discussions, the development mechanism of Energiology is established as a developing model of the discipline, the driving force of which is produced by perpetual interactions between Energiology and the society.

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Biomass is a carbon neutral material, and the development of processes for the use of the bioethanol is accelerating worldwide as the demand for its use as an alternate transportation fuel increases. Bioethanol has already been put to practical use in Brazil and United States.
Today, sugarcane and corn are two of the materials used as the raw material in biomasses; however it is necessary to develop technology that uses lignocellulosic biomass as a raw material that can be used in large quantities at low prices because of the need to reduce the production costs. Thus, it is necessary to rationalize the process involving the resolution of biomass, the saccharification and co-fermentation of the cellulose and the process for refining the ethanol generated. In this report, we examined rationalization of the ethanol refinement process. The pressure swing adsorption (PSA) and membrane methods were examined as rationalization processes. With the membrane method the driving force for the dehydration becomes small in the high purity region, for example at more than 99wt%, and so an excessive membrane area is required. With the PSA method it is necessary to recycle the adsorbed water to the distillation column because of the need to recover the dissolved ethanol in the adsorbed water. A Hybrid process is proposed in which water is roughly removed until the level of 99wt% of the ethanol by the membrane method, and the ethanol is then dehydrated to a high purity afterwards by a small-scale PSA method. This Hybrid process is most advanta-geous from the viewpoint of energy and the equipment expense. When the content of the acetic acid in the bioethanol goes to 50 mg/kg, distillated ethanol of 85wt% may be supplied to the Hybrid process from a viewpoint of saving energy and equipment costs.

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A sustainable society can be created by establishing a positive feedback loop of the supply of Green Products and Services (hereafter called GPs) by businesses that will be able to contribute to the creation of a sustainable society and demand of GPs by users (customers). In order to promote the development of GPs and the diffusion of GPs, easily understandable criteria for judging GPs that can be shared among “designers and developers”, “managers” and “users (customers) ” are necessary. However there is no general means of measuring and evaluating specific target products, and the standard assessment method is yet to be established. Therefore, the “Factor X Tool 2001” independently developed as a GP indicator is proposed in this paper. And the way to calculate 'Factor X' ('Eco-efficiency') is explained by using the case study of applying “Factor X Tool 2001” to washing machines. After that, this paper verifies the effectiveness of this indicator by comparing with the Factor X calculation method developed by Mitsubishi Electric Corporation that has publicized calculated Factor values in the electric and electronic industry.

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