Research on the Thermal Environment of Northeast China's Rural Residences

Rural residential energy consumption accounts for 46.6% of total building-related energy consumption of China. In Northeast China, energy consumption for space heating represents a significant proportion of total rural residential energy consumption and has reached 100 million tce (tons of standard coal equivalent), or more than 60% of total household energy consumption. In terms of energy consumption per square meter of gross floor area, rural residential energy consumption for heating is more than that of cities (20kgce/m2). However, the average indoor temperature of most rural residence is below 10°C, much less than that in cities (18°C). Hence, it is an important task for Chinese energy saving and emission reduction to reduce rural residential energy consumption, while enhancing indoor thermal comfort at the same time. Restricted by local technology and low economic level, rural residences currently have poor thermal insulation resulting in severe heat loss. This paper reports on research aimed at developing design strategies for improving thermal insulation properties of rural residences with appropriate technology. A field survey was conducted in six counties in severe cold areas of Northeast China, addressing the aspects of indoor and outdoor temperature, humidity, internal and external surface temperature of building envelop enclosure, and so on. The survey data show the following: 1. Modern (after 2000) brick-cement rural residences perform much better than the traditional adobe clay houses and Tatou houses (a regional type of rural residence in Northeast China – see figure A) in overall thermal performance and indoor thermal comfort; 2. Among the traditional residential house types, adobe clay houses have better heat stability and thermal storage capacity than Tatou houses; 3. Applying an internal or external thermal insulation layer can greatly improve rural residential thermal insulation properties, and is an economical and efficient solution in rural areas; 4. In terms of roofing materials, tiled roofs show much better thermal insulation properties than thatch roofs; 5. Adopting passive solar techniques can form a transition space (greenhouse) against frigid temperatures, resulting in interior temperatures 5.91°C higher than the outside surroundings. It is evident that local passive solar room design offers significant heat preservation effects and lower cost ($12/m2), embodies the ecological wisdom of rural residents, and is therefore important to popularize. The above experimental results can provide guidance in energy conservation design for both self-built residences and rural residences designed by architects. In addition, the results can also provide experimental data for energy-saving studies for rural residences in China.