Skip to main content

如何计算Degree Days

learn.whatIsHeading

Heating and cooling degree days quantify heating/cooling needs based on temperature deviation from base (usually 65°F/18°C).

公式

Heating degree days (HDD) = sum of (65 - daily avg temp) for days below 65°F
HDD
sum of (65 - daily avg temp) for days below 65°F — sum of (65 - daily avg temp) for days below 65°F
F
F value — Variable used in the calculation

分步指南

  1. 1Heating degree days (HDD) = sum of (65 - daily avg temp) for days below 65°F
  2. 2Cooling degree days (CDD) = sum of (daily avg - 65) for days above 65°F
  3. 3Higher values indicate greater heating/cooling needs

例题解析

输入
City: 5000 HDD/year (cold climate), another 1000 (warm)
结果
Cold climate needs 5× more heating, affecting system size and fuel use
Major design driver

常见错误注意事项

  • Assuming heating and cooling degree days sum equally (different impacts)
  • Using wrong base temperature (varies by building type)

常见问题

Why use degree days instead of average temperature?

Degree days directly correlate with energy use; capture heating/cooling needs more accurately.

Can you estimate energy use from degree days?

Roughly yes; heating energy ≈ HDD × building UA / efficiency. Useful for screening.

准备好计算了吗?尝试免费的 Degree Days 计算器

自己尝试一下 →

设置

隐私条款关于© 2026 PrimeCalcPro