When you change the initial intensity of a light source, the change affects all relevant model views. 
For example, if you want to change the bulb in a table lamp from a 60 watt bulb to a 100 watt bulb, change its Initial Intensity value. 
- In a project view, select a lighting fixture, and click Modify | Lighting Fixtures tab
Properties panel
 (Type Properties).  
- Click Duplicate to create a new type. 
 
- Enter a name for the type, and click OK. 
 
- In the Type Properties dialog, for Initial Intensity, click in the Value column. 
 
- In the Initial Intensity dialog, specify the desired value.