Going
Green
How much Electricity Does my Computer Use?
The formula to figure out much you’re spending each year on using
your computer goes like this: A watts / 1,000 = B kilowatts * C hours
per day of usage = D kWh * $0.13 (rate you pay from electricity company
per kWh) = E (cost per day) * 365 = F (cost per year).
- A typical desktop computer (not including the monitor) uses
about 65 watts give or take a few watts depending on the computer.
- The typical desktop in hibernation uses about 3-35 watts
depending on the hardware.
- A typical CRT (the big computer monitor) takes about 80 watts
give or take a few.
- A typical LCD (small flat monitors) uses about 35 watts give or
take a few.
Example of a desktop computer with a old CRT monitor running 24 hours
a day.
165 watts / 1,000 = .165 * 24 (hours per day) = 3.96 * .13 (cost
per kWh) =
$.51 (per day) * 365 = $187.90 (per year)
Example of same desktop and the money you would save shutting it off
for 8 hours a night.
165 watts / 1,000 = .165 * 8 (hours per day) = 1.2 * .13 (cost
per kWh) =
$.16 (per day) * 365 = $56.94 (per year) saved shutting
off pc & monitor for 8 hours
Some ways to Save Electricity and money
- Buy a laptop instead of a desktop, if practical. It consumes
five times less electricity.
- If you buy a desktop, get an LCD screen instead of an outdated
CRT.
LCD monitor uses about one-third the energy of a CRT monitor.
- Enable the power management function on your computer, the
screensaver does not save energy.
- Switching off a computer extends its lifetime, contrary to some
misconceptions. Leaving a computer running the whole year will cost
you more than 1,000 kWh/y, or almost as much a the total electricity
consumption of a high-efficiency household.
- Turn it off when you are not using
it for more then an hour - At least shut off the screen. 60% of the
power used from a computer is used by the display screen; the other
40% is used to keep your hard drive spinning and to power the
electronics.
- Use one large power strip for your computer, broadband modem,
scanner, printer, monitor, and speakers. Switch it off when
equipment is not in use. This is a practical way to cut 200 kWh/y or
more of standby losses.
- Minimize printing. Laser printers use more electricity than
inkjet printers.
Find many links by searching the web for
Going Green with your PC.
