Wednesday, August 30, 2017

Autodesk Climate Server

The Location setting provides localized weather and utility rates data which is vital in creating a legitimate energy simulation. There are two steps involved in accurately specifying location; Project Address and Weather Station.

Project Address specifies the project location on earth within Revit. This can be a city, a specific postal address or Lat/Long values. If the project site does not have an address, enter the City name and then drag the Project Location Pin (red) to the desired location on the map. You can zoom and pan in this map view as well as make the dialog larger.

Once the geographic location has been specified...
the Weather Station options should be evaluated. Revit will automatically select the closest option, but this may not always be the best selection. Consider the example shown in the image below. In my location, two of the closest stations have an 800 foot elevation difference. Additionally, depending on project location in this area, one of the two buoy-based weather stations may be closest—which would not be ideal (this is the largest freshwater lake in the world, by surface area).


A common question is: where does this weather data come from? The answer to this question can be found via the links below. Even if you have not considered this question, I recommend you read through this information to familiarize yourself with the inter-workings of the entire energy modeling workflow and feature set in Revit, Insight and Green Building Studio!

Insight blog post: Climate Server: A Hidden Gem in GBS

Autodesk Knowledge Network (AKN):
Here are a few quotes from Autodesk’s help pages:
“Weather stations include ‘actual year’ virtual weather stations and typical year weather stations (TMY2 and other formats) based on 30-year averages of weather data, typically taken from airport locations.”
"The Autodesk Climate Server is a distribution channel that aggregates and delivers climate and weather data from several sources, using several methodologies:"
"Climate Server is an Autodesk-maintained database of over a million virtual weather stations that are based on sound meteorological science and research. This is the data that drives energy analysis in Green Building Studio, Revit, and Vasari. Most of this data can also be downloaded from GBS."  DJS - Note that Vasari does not exists anymore.
The weather data includes the following fields, for each hour of the year:
  • Global horizontal radiation (Wh/m2, amount of energy striking a horizontal surface during the hour)
  • Direct normal radiation (Wh/m2, perpendicular to the sun's rays)
  • Diffuse Horizontal Radiation (Wh/m2)
  • Total sky cover (tenths covered, visual estimate of proportion of cloud covering the sky)
  • Dry bulb temperature (deg C)
  • Dew point temperature (deg C)
  • Relative humidity (%)
  • Pressure (mb)
  • Wind direction (degrees)
  • Wind speed (m/s)
This list is from this AKN link: Weather Variables and File Formats

Monthly Temperature and Windrose Speed Data

Within Insight, you can click on the Location tile next to the 3D view of the EAM (see first image below). Clicking on any of the visible weather stations will reveal Monthly Temperatures and Windwrose Speed data as seen in the last two images.