Contrastive study between the biomass energy utilization structure and the ecotype energy utilization structure in rural residences — A case in Hunan province, China

The purposes of this study are to look into the actuality of rural residential energy consumption in Hunan province, China, to improve rural residential energy utilization structures, and to protect the environment. An investigation on rural residential energy consumption was carried out in the villages of Xintian and Jiangwan in the spring and summer of 2005. Biomass energy is used in Xintian while biogas is popularized in Jiangwan. A questionnaire survey covered basic information of residences in the two villages, and energy consumption data of each family in the spring and summer were also recorded continuously. The characteristics of energy utilization structures of the two villages, the one with biomass energy utilization structure and the other with the ecotype energy utilization structure, are contrasted, and seasonal variance characteristics of energy consumption in spring and summer are analyzed. Sequentially, influence factors of rural residential energy consumption are further discussed qualitatively and quantificationally. Environmental benefit is assessed finally when biogas substitutes biomass energy. Conclusions are summarized as follows: In Xintian, a complicated energy structure is still dominant, where biomass energy accounts for a significant proportion and manifold energy resources exist simultaneously; the energy consumption is high; categories of energy resources used by households vary between spring and summer. The energy structure is definitely better in Jiangwan, where the ratios of commercial energy and ecotype energy used are both higher than those in Xintian and the ratio of biomass energy is smaller. Categories of used energy resources are also more constant in spring and summer. The total energy use amount of each season in Xintian is larger than that in Jiangwan respectively, while there is little difference in the efficiency energy use amount of each season between the two villages. Qualitative and quantitative analyses show that the accessibility of local energy resources, the domestic economical level, governmental energy policies, and consumption conceptions of farmers affect energy utilization structures definitely, while the efficiency of cookers, the number of family members, and annual income have effect on energy consumption amounts. Environmental analysis shows that the usage of biogas makes a great contribution in optimizing the energy consumption structure, reducing energy consumption, discharging less harmful gases and keeping the ecosystem in balance. The comparison between biomass energy and ecotype energy provides instructions for future development of rural residential energy consumption in China.