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Ecotect Tutorial : Calculate Artificial Lighting using Points


This tutorial explains how to calculate and display artificial lighting levels using points in an Ecotect model.


You will need about 10 minutes to complete this tutorial.

Training and Accreditation

Successfully completing this tutorial fulfills one of the practical skills required for completing Level 1 of the Artificial Lighting training module.

Resources Required

To complete this tutorial, download and open the file located under the Attachments' section at the end of this tutorial.


  1. The Ecotect file contains a simple thermal model consisting of a single zone, some light objects and an array of point objects. We need at least one of each of these objects in order to perform an artificial lighting analysis using points.
    You need at least one zone, one point and one light in order to perform an artificial lighting analysis using points.
    You need at least one zone, one point and one light in order to perform an artificial lighting analysis using points.
  2. Start the calculation wizard by selecting the Calculate»Lighting Analysis... menu item. Select the Overall Daylight and Electric Light Levels radio option, and then click Next.
  3. The next wizard screen allows you to choose whether points or an analysis grid is used for the calculation. As we only have points in this model, the At Specific Points in the Model is selected by default. If you wish to isolate the analysis to only certain points press F2 to return to the model, select the required points, and then press F2 again to check the Selected Points Only checkbox option. Click Next when you are ready to proceed.
  4. Specify how precise you would like Ecotect to be with its calculations. Usually, the default setting of High is suitable for most calculations, however this can be varied using the slider. Naturally, the greater the precision, the longer the calculation processing time required.
  5. Even though you are analysing artificial lighting levels, it is still necessary to specify the Design Sky Illuminance in your model. This allows you to compare electric lighting levels to those provided by daylight either together or in isolation. If you are unsure of how to calculate or adjust these settings, accept the default selections offered by Ecotect, and then click Next.
  6. You can specify room based settings on the next wizard screen. These only relate to the calculation of daylight factors, and so do not affect the results for artifical lighting. Leave these settings as they are, and then click Next.
  7. The final wizard screen presents a summary of all of the settings you have selected. Make any adjustments, if necessary, and then click Ok to commence the lighting analysis.
  8. Ecotect takes a few moments to calculate the lighting levels based on the settings you have specified in the wizard. However, you will need to check that Ecotect is actually displaying the values you are interested in examining. Go to the Display Settings control panel, and under the Object Attributes section, make sure that Electric Light (Lux) is selected from the drop-down list. Also try out the Show Colours checkbox.
  9. In this particular model, the current lighting design does not provide adequate lighting levels around the perimeter of the room (not surprising, really). Changing the distibution of the lights, and the type of luminaires selected will help to address this issue. As you can see, Ecotect can be a valuable tool to quickly assess different lighting designs for their effectiveness.


  • Ecotect uses the Point-By-Point method for determining artificial light levels within an enclosure. This simply calculates the sum of contributions from all light sources actually visible from each measurement point. The contribution of diffuse light is not calculated in this method. Thus, the lighting levels produced using this algorithm are to be used only as a guide during initial decision-making as they provide a relative scale from which to measure the effects of different model changes.
  • If necessary, Ecotect can export your model to Radiance for a more comprehensive lighting analysis.
Ecotect Tutorial : Calculate Artificial Lighting using Analysis Grid


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Calculate Artificial Lighting using Points

comment posted by MLH :: 11 April 2008 - 1:26pm

I could not find the Attachment:



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