After several years of work, the U.S. Environmental Protection Agency today launched its Energy Star for Enterprise Servers certification, the latest addition to the EPA's overall goal to improve data center energy efficiency. The new certification will allow manufacturers will cover all non-blade servers with one to four processors and at least one hard drive to apply for Energy Star certification as highly energy efficient devices. Energy Star for Servers will measure three main categories of performance: managing power supply performance, functioning in a virtualized environment, and energy benchmarks for measuring and reporting server energy use. Blade servers are not yet covered under the first version of the specification, nor are servers with no installed hard drives -- the EPA is still developing a measurement that can equitably compare blade servers with traditional servers.