When Microsoft created Vista they realized that they had to do a better job with conserving batteries and energy. Laptops are getting to the point where they last as little as an hour when they are brand new, and that not only reduces productivity but it also means they consume more electricity.
In Vista you’ll see a completely revamped power management screen in the Control Panel, and with it you can choose between several different “states” you want your computer to run in. The best part, however, is that you can completely customize your own power plan, and that’s what I’ve done. In my power plan I have cut back my processor speed, screen brightness, wireless performance, and more when my computer switches into battery mode. Not only does that save my battery life, but it also reduces my PC’s CO2 Emissions.
Out-of-the-box Vista PC’s run in a “Balanced” mode that gives your computer the performance it needs when you’re doing intensive tasks, but reduces it when you’re doing simple tasks like word processing. This is a feature that Microsoft never put in XP, and it can make a real difference on the environment.
Below is a table that shows you what the cost and emissions are on computers running Windows XP and Vista (just the computer, no monitors). The results come straight from Microsoft, and I’m sure there is a little exaggeration but their tests are well documented (PDF). They tested three computers for all of their results, but I took the liberty of averaging them together and converting them into U.S. dollars:
| Windows XP | Windows Vista | Vista Savings | |
| (1) Computer Annual Cost | $110.17 | $36.44 | $73.73 |
| (200) Computers Annual Cost | $22,033.37 | $7,287.59 | $14,745.78 |
| (1) Computer CO2 Emissions | 259 kg | 85.33 kg | 173.67 kg |
| (200) Computers CO2 Emissions | 57.13 tons | 18.89 tons | 38.24 tons |
As you can see there is a big benefit for corporations who run Windows to make the upgrade to Vista, in terms of energy savings and emissions produced. 
This article was written in part for Blog Action Day.
XP users can use Performance on Demand (and other kinds of profiles) by installing the RightMark CPU Clock Utility. It runs my 2GHz CPU on 800MHz when I don’t need its power (most of the time).
The “Blog Action Day” link is incorrect, it ends in a 404.
Good to know Microsoft improved energy consumption in Vista (look, something worthwhile
), but I wonder if it would be an energy saver in desktop PCs as well…
There are several different applications that do stuff like this, but not to the extent of what Vista does. Vista also cuts back wireless performance and other things.
Thanks, I fixed the link. It can be an energy saver on a desktop as well depending on what you set your power plan to. The power plans are not just for laptops.
I just measured that my six-months old Vista dualcore-machine uses only 10 watts more energy than my four-year old computer using the power savings options.
Normally I let the processor use 100% performance when needed but when I have to leave my computer on overnight I’d like to easily switch to a power saving plan. I’ve tried unsuccessfully to find a widget or something to do this with one click.
Wow, just 10 watts more for a dual core machine! That’s pretty darn good.
Seems to me that I’ll be using the “balanced” option most of my time and the “high performence” (with the charger plugged in) when doing presentations…
Balanced is definitely the route to go by default. It gives you the best of both worlds. I actually created my own custom power plan, but it is extremely similar to balanced.