Power-conscious chips: When it comes to energy efficiency, AMD has dominated a two-horse race with Intel, increasing the number of cores in its Opteron chips while holding power consumption steady. Intel also markets its Xeon line of energy-efficient server processors and recently announced it will begin making chips using a new insulating material that consumes less electricity, generates less heat and delivers faster processor speeds. Now a startup, P.A. Semi, is getting into the act with the development of its family of 64-bit, dual-core PWRficient processors. The company claims its chips will be three to four times more energy efficient than competing products. \n\nEnergy-efficient servers: Thermal engineering\u2014once an afterthought\u2014has become a critical limitation for servers. Manufacturers such as IBM, Hewlett-Packard and Sun Microsystems have taken steps to redefine system design and improve internal blower and fan technologies. IBM touts its System z mainframe as a power-efficient alternative to high-density x86 servers for Linux applications. Sun, meanwhile, says its Niagara servers use half the power and offer three times the performance compared with competitors\u2019 machines.Better cooling and power supplies: Power supply vendors such as APC and Emerson and HVAC manufacturers including SprayCool and Cooligy (which is owned by Emerson) are developing products that target global warming. These include systems that use carbon dioxide for cooling (in place of more harmful refrigerants), direct-current power supplies (more efficient than converting alternating current from the electrical grid) and more efficient in-chassis, in-rack, in-row cooling products.Green design: Server manufacturers and IT service providers have ideas for more efficient data center designs. HP is working on a next-generation modular data center prototype that incorporates virtualization and a closed-loop cooling system, among other features. Sun Microsystems is touting its Project Blackbox, a virtualized data center built into a shipping container and optimized to deliver energy, space and performance efficiencies. In addition, a who\u2019s who of data center vendors is sponsoring a nonprofit IT user group called Green Grid, which focuses on best practices for managing data center power and cooling issues.Financial incentives: Customers of Pacific Gas & Electric are eligible for a rebate of up to $4 million for virtualization projects that consolidate servers. The California utility also offers cash rebates for the installation of other energy-efficient products such as servers and HVAC equipment. The EPA is studying what other incentives might encourage businesses to adopt eco-friendly technologies.