General Status of Building Energy Consumption in China: Survey and Comparison

1. General Status of Building Energy Consumption in China: Survey and Comparison Borong LIN, Dr. Associate Professor Building Energy Research Centre Tsinghua University, China Mar., 2008

2. Content • Chinese building energy consumption data • Comparison between China & developed countries • Stratagem to rising Chinese building energy efficiency

3. Chinese building energy consumption data • Building energy investigation from 1995 • Data source • China yearbook • On-site survey and statistics • Two dominating energy sources in bldg. • Coal Consumption • Heating in Buildings in North of China • Electricity Consumption • Rural • Urban

4. Survey on Building Energy consumption Classify energy consumption for urban bldg. Heating in Buildings in North of China Energy consumption in buildings excluding heating Residential Bldg. Ordinary Commercial Bldg. Large-scale Commercial Bldg. Relating to Manufacture Procedure Industrial bldg. All Bldg. in China Res. bldg. in rural area 70% is bio-energy 30% comm. energy Civil bldg. in towns & cities Major part

5. BEC in China - Breakdown Heating at North China Rural area Heating at Yangzi River 1% Large-scale Commercial 4% Residential building except heating 16% Ordinary Commercial 19% BEC in each sector Building area in each sector

6. Current situation - Breakdown BEC accounts for 25.5% of Total social terminal energy consumption in China

7. Building energy data from different countries Building energy data by per participant [kWh/(p.a)] Building energy data by floor area [kWh/(m2.a)] Comparisons Data source: EIA 2005

8. Differences in BEC • Urban residential in China: • Less domestic hot water service • Difference in operation • High consumption in heating • Commercial buildings • High standard LCB: same level • Normal commercial: much lower • Rural residential in China: • 70% of energy are primary bio-energy • Much low living standard comparing

9. BEC comparison- residential buildings

10. BEC in rural area • 60% of total building area 35% of BEC commercial energy 7.5~15kWh/m2.a • Commercial energy consumption: 1/3 of urban residents in terms of per m2 • Primary bio-energy (firewood, corn stalk, etc.) takes a great portion (no accurate data) • No accurate data about primary energy, being investigated

11. Comparison between China urban & US • Heating energy: same level • Electricity: large difference Terminal energy converted to electricity equivalent Data source: 2005 Buildings Energy Data Book, U.S. Department of Energy

12. Reasons for difference • Different operation manner • Less domestic hot water consumption • Only 60% of families have hot water system • Less than 10% in total energy consumption • Part time part space AC • 2~3 rooms in 6 rooms run AC • Most of AC run less 200 hours per year • Economizing custom • lighting is well controlled manually

13. Energy Comparison for Residential (kWh/m2.a) 中国此部分能耗水平是美国的1/4，日本的60% About ¼ of USA and 60% of Japan.

14. BEC comparison- Heating in North China

15. Heating Energy Comparison Heating Energy consumption comparison Field investigated heating energy data in Beijing 83kWh/m2a Germany France Greece Denmark Beijing, China Beijing VS. city of developed countries

16. Parameters of heating Factors on Heating 影响采暖能耗的参数 建筑构造 Building structure 运行性能 Operation 运行时间 Length operation 保温水平 Insulation 体型系数 Shape factor 渗风量 Infiltration 室内温度 Indoor temp. Insulation Shape factor Infiltration Operation time Indoor temp. Beijing: 120days Northeast: 170 China 中国 Close window: 0.5～1/hr Open window :3～10/hr 18~20℃ 0.2~0.5 1 Any time If needed Europe 欧洲 18~22℃ >0.5 ½ ~ 1/3 1~2 /hr 因此，中国采暖能耗并非是发达国家的2～3倍，而是基本差不多 Therefore, heating energy consumption level in China is similar to developed countries.

17. BEC comparison- commercial buildings

18. EC in LCB Data source: on-site survey by THU; Dissertation, Xue Zhifeng, 2005 LCBs in Beijing Shoppingmall Hotel Office Government LCBs worldwide

19. Comparison about LCB (Energy for heating in Chinese buildings excluded) Data source:Environment Management for the Sustainable Building. Japan，2004

20. Case Study in USA • 1,3 million m2, Campus • Location: Philadelphia • distributed CHW System • Office Building • Laboratory • School Building • Hotels • Residential (few)

21. Energy consumption in campus buildings（China & US) Office 4,650m2，34kWh/m2.a Dental School 6,425m2，313kWh/m2.a Lab & Office 3,360m2，56kWh/m2.a School of Technology 27,000m2，64kWh/m2.a Business School 30,000m2，356kWh/m2.a School of Science 15,000m2，98kWh/m2.a

22. End-use electricity • More than 50% used by HVAC • Fans in AHUs of Buildings • Pumps: primary, secondary • Chillers

23. Investigation • Reasons for high EC • Counteraction of cooling and heating • Longer running time-24h • Different indoor temp. setting 20℃ summer • Factors causing large difference in EC between commercial buildings • HVAC System • Operation manner • Less related to technology

24. Factors influence BEC Real building Performance Energy (Good) Building envelope (Bad) (Low) Energy Consumption (High) (High efficient) System efficiency (low efficient) (Economized) Operation mode (Uneconomized

25. China’s BEC Stratagem

26. Main characteristics for BEC in China • Current situation • Relative lower than the level of developed countries • Large difference between buildings • Heating is the largest part • Development • Growing rapidly with the development of economy and civilization • Energy efficiency work for China • Big challenge • Different way from developed countries • Economizing custom should be called for

27. Prediction of BEC in China in 2020 (Considering improvement of urbanization and living condition)

28. Prediction of BEC in China in 2020 Energy source: <International Energy Outlook 2005>

29. Big challenge for China: • Demand • Keeping Economic Growth • Improving living conditions • Limitation • Energy Supply to meet the requirement • GHGs Emission and Climate Change Responsibility • Different way from developed countries • Find a unique approach and contribute to the world

30. Key Points of BEE Works in China • Reduce EC for large-scaled commercial building • by new tech, strict evaluation and LC Commissioning to new buildings, and improving management, operation and control in existing buildings • Improve living conditions for rural area • by developing a sustainable approach to improve the living standard • Improve service quality for residential & ordinary Com. • by promoting high energy efficiency appliances and keeping energy-saving habits • Reduce EC for heating • by adding additional insulation and improving system efficiency • Satisfy the indoor environment demand in Yangtze River area with low EC • by developing new heating and cooling technologies and strategies

31. Conclusion • Energy consumption is related with complicated matters including: building fabric, energy utilization efficiency, living and operation mode • Commercial buildings • Residential buildings • Building energy development in a distinct way is a big challenge for China and the world

32. Thank you for your attention Borong LIN linbr@tsinghua.edu.cn Tsinghua University