Microsoft Says Windows 7 Is as Green as It Gets

Microsoft wants Windows 7 to be seen as green.

In an interview with eWEEK, Rob Bernard, Microsoft's chief environmental strategist, insisted that the company's newest operating system will come with environmentally friendly features baked into its infrastructure, creating greater energy efficiency (and a smaller carbon footprint) than Windows Vista or Windows XP.

"Windows 7 is the first [Microsoft] operating system to operate at this granular level" of control over energy-saving options, Bernard said. For example, "the server and client interaction allows IT [departments] to run a power-efficiency diagnostics chart" and then use that information to adjust PCs for optimum operation. IT administrators can use Group Policy, WMI (Windows Management Instrumentation) and Powercfg.exe, a command-line power management utility, to centrally manage power settings.

The Windows 7 developers were detail-oriented in their approach to energy efficiency. For example, the operating system detects which hardware ports have a device attached and powers those, as opposed to the old and marginally less efficient method of tapping each port for a plug-in. Users can click on the battery icon and select a "power plan" that offers choices over elements such as screen brightness.

System display brightness can account for as much as 40 percent of overall system power consumption; with Windows 7, the screen can dim but not go completely black when the system is left idle, saving energy but not frustrating the user with the need to awaken a black screen. Windows 7 will also reduce consumption in other areas, such as by reducing power to the wireless NIC (network interface card) when the system is plugged in, or placing the network adapter in a low-power state.

But how much of a change from previous operating systems do such steps represent?

"The most important thing an OS can do for 'green' is to not subvert the power efficiency measures that are built into the hardware," Steve Kleynhans, an analyst with Gartner, said in an e-mail to eWEEK. "In the past it was not uncommon to find that certain device drivers or the way that some scheduling was done would prevent the processor from operating in its most power-efficient way.

"Windows 7 has removed some of that and has become much more aware of (and friendly to) the power management capabilities within the processor and chip set. For the most part we aren't talking massive reductions in power, but every little bit helps when you multiply it by the millions of machines that will run Windows 7 and the thousands of hours they will operate."

The operating system's default settings—when it sleeps, for example, how it utilizes resources when idle and how it manages processor power—have been designed to deliver energy savings. Much of the reduction in IT's carbon footprint, though, inevitably comes through hardware.

"The biggest improvements to the carbon footprint of PCs will continue to be related to changes in manufacturing, hardware operational characteristics and how users use the devices," Kleynhans said. "The OS can have some impact optimizing how the hardware functions, and possibly can sway usage patterns, but there is only so much it can actually accomplish."