Power management options in Windows XP and earlier versions of Windows can be used to save on power usage. However, the options are limited and lack a bit in control. Windows Vista has made significant improvements in power management options that allow users more control and more choices.
Improvements in Vista
Power management options in Windows XP pale dramatically in comparison to the new ones in Windows Vista. Windows Vista has made improvements in energy efficiency by leaps and bounds. Its default features will make a huge difference for the individual user. Its customization options are great for individual users and companies, alike. Some of the default settings that will make the biggest day-to-day differences include: All power off options set to send computer into Sleep mode, not shutdown. No need to differentiate between Standby or Hibernate—Sleep is the only option and it does everything it needs to. There’s a pre-set system idle timer for Sleep and a time out that will blank the display automatically.
Sleep and Resume in Windows Vista produces immediate results, no waiting for your PC to “wake up." Users can join Microsoft’s Customer Experience Improvement Program if they wish to send reliability data for Sleep settings back to MS. Microsoft claims this will help them continue to improve Sleep reliability.
Effects of Efficiency
Most notably, Sleep mode saves as much energy as shutting down your PC. The added benefit for users is that your PC will resume from Sleep much more quickly than booting up after a shut down. Microsoft claims it will resume in less than 2 seconds. Microsoft has shown that a PC with LCD display running 10 hours a day for 5 days a week as compared to one left running 24/7 saved 597.5 kWh annually. At the current cost of five cents to 17 cents per kWh for residential consumers, that would save you between $30 and $100 a year in energy bills. A company running 1,000 PCs with Windows Vista would save approximately $70,000 a year. As energy costs rise, so will your savings.
Microsoft tells us that 6 PCs running 24/7 require an acre of trees to eliminate the greenhouse gasses caused by those PCs. Windows Vista’s improvements reduce CO2 emissions to 926.16lb from the average of 1178.22lb. If every PC user in the U.S. made the same reduction in their homes, it would be comparable to taking millions of cars off the road. Corporations running thousands of PCs could obviously make an incredible improvement utilizing these features.
Microsoft is actively advancing green computing and research about green computing. Their Sustainable Computing Program focuses on energy demands of computers. To learn more about Microsoft's SCP, read this.