Art of Engineering


Energy Saving Tips for Computers


The typical PC and CRT monitor consumes about 350 to 600 watts per hour.  At 400 watts per hour, your PC is consuming clean air faster than you by a factor of 6.  (The power plant uses air to burn the coal to boil the water to spin the generator to make the electricity to power the PC.)

Turning off your computer when not in use saves energy and clean air. Here are some tips to reduce electricity consumption associated with computers.
 

ACTION Savings you might not have thought of
Switch from a CRT to a LCD monitor 14"  CRT electrical consumption = 49 watts
14"  LCD electrical consumption = 20 watts
And.... it takes up less space and is easier on the eyes!
Program your PC to turn off at a certain time of day

Here are the steps to turn off your
PC using:
Windows Task Manager (Win 98)  or Task Scheduler (Win XP) 
 

If a typical PC and LCD monitor consumes 300 watts per hour, if left on overnight (about 10 hours of non-use), 3 kiloWatt hours of energy is wasted.  If you've decided to use VOIP phone service because it's cheaper then the local phone company, the energy that having a PC for a phone system costs you about 16 hours at 300 watts for electrical costs (for a work day when your neither home or awake for about 16 hours).  Each month, the time when your away from your PC and it's solely a smart answering machine, it's costing you $9.21 for the electricity to answer the phone and consuming 20,175 cubic feet of breathable air to make that electricity.
Eliminate 'ghost loads'

Ghost loads are those little draws of electricity that keeps memory or remote control features awake even when your not using the device.  Transformers are a common ghost load.

Even while turned off, many PC's continue to consume energy due to the 'wake up' functions.  It's not uncommon for a PC to consume 35 watts of power when turned off.  That means while you sleep, your PC is consuming clean air faster than you are!

Our DSL modem consumes 6 watts while turned off due to losses in the transformer supplied.  It consumes 8 watts when in use.  If  left plugged in during nights and weekends,  the ghost loads consumed add up to 708 watts per week or 36.8 kWhrs of electricity wasted each year by this single modem.  This costs about $3.00 and puts 460 pounds of pollution into the air.

Consider this, for each kiloWatt hour of electricity you use it costs you about 8 cents (in 2006).  To make that kiloWatt of electricity it's 90% certain that it came from burning about one pound of coal.  One pound of coal being burnt creates a significant amount of air pollution and health hazards.

Plug all office electronics into power strips that you can easily turn on and off for the work day.  A surge protected power strip is always a good idea.

By having these devices plugged into a strip: 

PC                            35 watts 
DSL modem                6 watts 
Printer                       30 watts 
another device            25 watts 
                                  ----------- 
                                 96 watts * 14 hours = 1.344 kW hours
                                of  energy saved 

To make that energy that is wasted, the power plant would have to have burned 1.4 pounds of coal, which it sucked in 175 cubic feet of breathable air and emitted 17 pounds of pollutants, every day. Of the 17 pounds of emissions, 2.3 pounds is CO2 and a very large amount of nitrous compounds as well as sulfur, mercury and many trace elements.
  

Program your computer to turn off:

Task Manager (Windows 98)  or Task Scheduler (Windows XP)

Follow these steps to turn your PC off.  Make sure your data is saved and the auto save feature is turned on on your software.  Use an timer to turn off all the AC to your PC and monitor to eliminate those 'ghost loads'.

1.   Click Start, and then click Control Panel.
2. Click Performance and Maintenance, and then click Scheduled Tasks.
3. Double-click Add Scheduled Task. The Scheduled Task Wizard starts.
4. Click Next.
5. Under Click the program you want Windows to run, click Browse.
6. In the Select Program to Schedule dialog box, locate the %SystemRoot%\System32 folder, locate and click the Shutdown.exe file, and then click Open.
7. Under Perform this task, specify a name for the task and how frequently you want this task to run, and then click Next.
8. Under Select the time and day you want this task to start, specify a start time and date for the task, and then click Next.
9. Type the user name and password to run this task under, and then click Next.
10. Click to select the Open advanced properties for this task when I click Finish check box, and then click Finish.
11. Click the Task tab.
12. In the Run box, specify any additional parameters that you want to use with Shutdown.exe.
13. Click OK.