In the past the concentration of population in the big cities of Korea led to the neglect of the interests of the rural population. Of late even though living conditions have become visibly better, sanitary conditions have not been attended to and consequently have remained bad. In the course of a research programme, which took place between German and Korean institutes, not only the utilisation and treatment of nightsoil, but also model types of toilets, suitable for Korea, were examined. Based on the results of investigations of 4 different types of toilets, a new type (KISTLET) was developed, especially for rural areas with limited water supply and without sewage systems.
Up to 1975 about 29 000 simple biogas plants had been set up in Korea. In order to avoid the disadvantages of small plants a central plant with a digester capacity of 100 m was built. 19% of the gas produced was used for heating the digester, and warm water was prepared using solar energy. This plant was followed by a larger plant with a digester volume of 600 m. A rural household could save 32% of its energy expenses by using biogas.