Optoelectronics, Optics, Lights and Lasers
May 21, 2012, 12:01:19 PM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News:
 
   Home   Help Search Login Register  
Optoelectronics, Optics, Lights and Lasers > Non-Coherent Light Sources > Incandescent Lamps > 

the common exit sign in a public building uses two 20W incandescent bulbs. These could be?

Pages: [1]
« previous next »
  Print  
Author Topic: the common exit sign in a public building uses two 20W incandescent bulbs. These could be?  (Read 339 times)
abnrml
Newbie
*
Posts: 1


View Profile
« on: May 28, 2011, 04:43:21 AM »
replaced with LEDs at 2W per sign. If there are 40 million signs in use in the US, what savings in electricity use for an entire year could be secured with this changeover?
Logged
za
Newbie
*
Posts: 2


View Profile
« Reply #1 on: May 28, 2011, 05:17:11 AM »
Saving 18 W per sign.  40 million signs, saving 72 million watts.  About 30 million seconds in a year (assuming the signs are permanently on) , so saving is about 2000 000000 000000 joules.

At around 4 000 000 J per kW hr, that makes 500 million kW hr.  Worth having
Logged
Pages: [1]
  Print  
« previous next »
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.13 | SMF © 2006-2011, Simple Machines LLC | Privacy Policy Valid XHTML 1.0! Valid CSS!