feature focus
Cross-Discipline
Figure 2- The best orientation for the Las Vegas weather file is represented by the yellow line in the NW direction, at 335 degrees
Identifying Trends Not all buildings we design are in our own backyard. When we don’t have an intimate knowledge of the climate, Ecotect helps us do a little investigating. Trends such as percentage cloud cover, wind speed averages, solar radiation, and temperature can identify candidates for on-site renewables such as wind and solar. These metrics may be studied individually or displayed at the same time to see correlations between data points. Refer to Figure 3 for an example of weather data.
Figure 3- Example of weekly weather data - Direct Solar Radiation
The Weather Tool also helps identify what passive design strategies work best for a given climate. From the View menu, selecting the Passive Design analysis allows the choice of one or more of six different passive strategies. By specifying the hours of operation, or when a building is occupied, you can see the results displayed alongside the standard conditions (with no passive strategies employed). Refer to Figure 4 for another weather data example.
18
www.autodeskcatalog.com/AECEdge
Figure 4- Another example of some weekly weather data Maximum Temperature
In the example of an office building located in Seattle, we can see that the best strategy is a night purge system (see Figure 5). During the summer months we can expect a comfort percentage of between 75 and 95%, which potentially reduces the need for mechanical cooling. With this information in hand early, planning and systems design conversations with an HVAC engineer can take place in a meaningful way. Of course, once the building design begins to take shape, and loads are applied, validation of this strategy can also take place within Ecotect.
Figure 5- The effect of passive design strategies on comfort percentage for each month can be seen by the red bars, in comparison to the yellow baseline
Understanding Tradeoffs One of the unique benefits of Ecotect is that you can automate much of the environment through scripting. There are many prebuilt scripts available with the application, as part of the training packages, and online at the Ecotect Wiki at: http://squ1.org/wiki. (Building your own scripts requires a certain type of dedication as documentation in this area is a little sketchy.) Here’s an example of a tradeoff in design and performance where you can see immediate results. By enabling the script called fall_2009