Issues in calculation of balance-point temperatures for heating degree-days for the development of building-energy policy

Effective building-energy policy can be developed only when the appropriate analysis is implemented in advance. The heating degree-day (HDD) method is a powerful tool for anticipating a national climate or annual heating demand for a heating period. The accuracy of the HDD method depends on the accuracy of balance-point temperatures, which represent regional building thermal performance and climate conditions. However, accurate local balance-point temperatures have not been determined for most countries. This paper examines a method of calculating balance-point temperatures based on local building thermal performance and climate. Detailed calculation procedures for heat gains and losses in buildings are described and corresponding issues are discussed. Regional building thermal performance and climate are the main factors involved in the process, which requires appropriate regional balance-point temperatures. To reflect changes in climate, and subsequent policy changes, many countries will require more consideration of regional balance point temperatures. Balance-point temperatures were revised in Korea as a case study. The colder and the more intense the building insulation standards, the lower the balance-point temperature turned out to be, compared with what the American Society of Heating, Refrigerating and Air-Conditioning Engineers recommends. There was a 2 degrees C difference in balance-point temperature between the coldest and warmest regions in Korea. Insulation standards that demonstrated the greatest impact on balance-point temperature and severity of climate were also not negligible.