The acceleration of diffusion of the DER (distributed energy resources) is hoped for because of the promotion for highly effective use of energy, especially in the house and commercial section in Japan. From this point of view, it is necessary to focus on the feature of DER such as intermittent renewable resources, low quality and low density. The purpose of our study is to clarify the demand of multi (involved low) quality energy and to solve the problem which is optimization of the energy network supply system whose alternative is DER system and large power grid. For these reasons, in this paper, we drew up and sent out questionnaires and analyzed them by CVM. After we evaluated the potential of the multi-quality energy supplying system, we concluded that low energy quality have enough possibility to supply for some of the home appliance.
A co-generation system for home use (CGSH) suitable for cold districts is investigated in this paper. The system aims at using the discharged thermal energy conversion (DTEC) in generating electricity and heating purposes. Using ammonia/water (AW) mixture as working fluid, the heat balance, heat demand and electricity demand, and the contribution ratio of discharged-to-demand heat are evaluated at conditions that correspond to those in the cold places. For a 24hour operation, the system has demonstrated efficiency in heating homes and energy consumption that corresponds to over 80% reduction in CO2 emission in case of discharged temperature of 60°C. A contribution ratio of discharged-to-demand heat over 63% is achieved when the exit temperature is 45°C. The environmental impact of the ammonia/ water cogeneration system (AW-CGS) is expected to be same as that of the engine-type cogeneration system.
Anaerobic digestion recovers renewable energy from garbage of municipal solid waste, which is not suitable for incineration because of its high water content. However, anaerobic digestion produces digestion residue and high BOD waste water. Adaptation of hyper thermal hydrolysis to dry type anaerobic digester does not require water treatment process, therefore increased the amount of electricity recovery. In this study, we calculated and compared the amount of surplus energy produced by standard methane fermentation and hyper thermal hydrolysis integrated process.