Weather Files

Weather Files in the VE

When performing thermal simulations the VE will use the selected hourly weather data file to drive the building simulation. In order for them to be picked up by ApLocate (The Weather/Location database manager), these weather files must be placed in the Shared Content\Weather folder. By default this is installed in the following location: C:\Program Files\IES\Shared Content\Weather

If Shared Content has been installed to a different folder you can point the VE to its location by selecting Help > Troubleshooting > Set Shared Content Folder.

The shared content installation includes weather files for the following locations.

Weather file sources
The standard simulation weather files are sourced from various places and converted into the standard FWT file format. Usually the fwt will have an abbreviation that points out where the data was acquired (e.g: EWY = Example Weather Year. These are individual weather years sourced from the MET office). Most files are sourced directly from the energy plus website. You can read about different weather sources here. The weather file formats the VE can read are .fwt (proprietary format) and .epw files.

Getting More Weather Files

Source Description Download/Purchase
CIBSE weather files
(for UK building regulations)		 CIBSE TRY & DSY datasets are required to run simulations using ApacheSim method in VE Compliance. These datasets are owned by CIBSE and each user requires a license to use them. IES acts as an agent for CIBSE and the licence to use the data may be purchased on our website. Click Here
Weather Analytics Access comprehensive weather data ranging from 33 years of historical weather to on-demand current conditions to accurate, hourly seven-day forecasts in convenient bundles, including:
  • Historical, gap-free, hourly climate data
  • Current conditions and forecasted weather data
  • Modeling and simulation climate data (TMY & AMY)
 Click Here
US Department of Energy Weather files for more than 2,100 locations can be downloaded from the US Department of Energy’s website. These are energy plus weather files and are in .epw format. Place them in the weather file directory and the Virtual Environment will be able to access them. Click Here
VE EPW Creators Users can try sourcing weather data and creating their own weather files using our VE .epw file generator. Files created with the VE .epw creator can only be used in the Virtual Environment. IES will not be held responsible for errors or omissions in the .epw files created by the user.

 		 UK EPW creator
EU EPW creator
METEONORM METEONORM can produce energy plus weather files for almost any location in the world. Users can either purchase a license or ask them to generate datasets for certain location at a cost of around €80 per file. Click Here
Prometheus Weather Files The PROMETHEUS project has produced a number of future weather files (.epw format) which can be used to 'future-proof' buildings against predicted climate change. The files were created using the UKCP09 weather generator. The weather files are currently available for 45 locations, 3 time periods and 2 emissions scenarios. Click Here
CIBSE Future Climate Files Future hourly weather series, based on the existing Design Summer Years (DSYs) and Test Reference Years (TRYs) which incorporate the UKCIP02 climate change scenarios, are available for 14 sites , for three time lines (2020s (2011-2040), 2050s (2041-2070) and 2080s (2071-2100)) and for four emissions scenarios (Low, Medium-Low, Medium-High and High) for each site. Click Here