I have been in countless buildings on a sunny, beautiful Arizona Spring day that have the A/C blasting, ceiling fans on, and every single light on, despite the abundance of windows! There is a simple way of reducing our voracious energy consumption that wouldn't cost a dime — TURN THE LIGHTS OFF!!
 
I've been in numerous restaurants that have large windows. It would be barely noticeable if every light were turned off because of the amount of natural light. I recognize that these establishments need to advertise and display their products and don't want to appear uninviting. But, having all the lights on, especially the more decorative ones and those close to windows, are really only necessary at night. I've been in spaces during March that have the A/C and every ceiling fan on when it's 70 degrees outside! Let's turn these things on and off at the appropriate times.
 
Architecture can voluntarily help in this endeavor with judicious use and proper placement of insulated, low-E windows with adequate exterior solar protection to lower the need for so many lights. We can greatly reduce A/C with proper insulation, roof overhangs, building orientation, materials and intelligent locations of windows and solid walls. Existing buildings can utilize awnings and tinting at windows as well as more energy-efficient A/C units. These are just some of the many passive solar techniques that can be used readily and at relative low expense.
 
The easiest way to help the environment that we can do now at no cost is to become more aware and adapt our habits. Businesses can greatly lower their energy demand and operation costs. They can also market that they have turned off a few lights in the name of saving our environment.