About Weather Data for the Cooling Load Calculation According to VDI 2078

Explains the concept of weather data in conjunction with the dynamic cooling load calculation based on VDI 2078.

Depending on the selected calculation method, you can select the weather data for the location of your project in Germany, Austria or Switzerland directly from a list or download it free of charge for other locations in Germany at the following address: https://kunden.dwd.de/obt/Climate data for other locations, which are not located in Germany, can be loaded into the cooling load calculation in the file format TRY. You can change the designation of the project site for the printout and alter the meteorological data to local conditions if need be.

Weather data for the Cooling Design Period

The meteorological data for the Cooling Design Period includes hourly temperatures for all 19 days of the CDP. If necessary, the data for the selected display month can be edited manually. To do this, you can either change the framework parameters and have a new temperature pattern generated, or edit the temperatures for the desired daily hours manually.

Weather data for the annual simulation

The German Weather Service’s meteorological data for the year simulation includes a selected number of meteorological parameters for each hour of the year. The data from series of measurements and observations, taken over many years by numerous German weather stations, will have been initially interpolated into the area. In a second step, the hourly data needed for the test reference years will have been extracted to the individual grid points (resolution 1km2). From weather periods that have actually occurred, the test reference years are then compiled in compliance with the measured values for the basic period 1995–2012.

For each hour of a year, each entry includes the following data:
  • Month, day, hour
  • Cloud amount
  • Wind direction
  • Air temperature
  • Water vapor emission
  • Relative humidity
  • Direct and diffuse solar radiation intensity relative to the horizontal surface
  • Radiation intensity of the atmospheric heat radiation relative to the horizontal surface
  • Specific transfer of heat radiation from the earth’s surface

For simulation under extreme conditions, test reference years, in each case with a very cold winter and a very hot summer, are also available. In addition, the suitability of the planned system for the future can also be checked, using a test reference year for the period 2031–2060. 24 regional climate models are the basis for this test reference year.

You can download the data for the year simulation as a ZIP file. The ZIP file contains the individual test reference years in *.dat format. You can download the data free of charge on the web pages of the German Weather service at https://kunden.dwd.de/obt/register.jsp?productId=TRY.