Green Embedded Solutions Focus on Energy Management

By Craig Szydlowski

Global warming and other environmental concerns are changing the way people live and do business. Customers worldwide are increasingly showing their preference for companies who practice social and environmental responsibility. Seeing opportunities to differentiate themselves, embedded-systems manufacturers are leveraging energy management to lower power consumption. These efforts allow customers to protect the environment and save money with an energy-efficient computing infrastructure.

Energy management requires a multi-pronged approach to address both the board and system levels. Boards are incorporating more energy-efficient processors and using software to transition power states when computing demand changes. Remote management systems also are helping to curb electricity usage. They shut off systems, such as cash registers, after a store closes.

Organizations and Standards

It may only be a matter of time before governments begin imposing taxes and penalties on companies that don’t practice environmentally good information-technology (IT) policies. For companies preferring a more proactive approach, some initiatives are already well underway:

  • IEEE P802.3az: Energy Efficient Ethernet Task Force Targeting to release a draft specification as early as September, this group is working on a standard to reduce the power consumption on 100-Mbit and Gigabit Ethernet networks. Under the proposal, Ethernet chips with no data to send would be able to put the physical layer (PHY) into a sleep mode. This option could save up to 1.5 W on Gigabit interfaces and 10 W on 10-Gbit interfaces. Furthermore, the team is looking at ways to turn off subsystems—the PCI Express bus, memory controller, and circuitry in the host processor—when there’s no incoming data from the network (http://www.ieee802.org/3/az).
  • Advanced Configuration and Power Interface (ACPI) This open industry specification, which was first released in December 1996, was co-developed by Hewlett-Packard, Intel, Microsoft, Phoenix, and Toshiba. It establishes industrystandard interfaces for operating-system-directed power management on notebooks, desktops, and servers. Although it’s been widely adopted by notebook systems to conserve battery power, the growing emphasis on energy conservation may expand the adoption of this specification.

The ACPI specification defines four global system states, G0-G3, as shown in Figure 1. These states are called Working, Sleeping, Soft Off, and Mechanical Off, respectively. Within each global state, there are sub-states that provide greater granularity for determining which system components are powered down (http://www.acpica.org).

Figure 1: Here are the four global system states defined by the ACPI specification.

  • The Green Grid This global consortium is dedicated to advancing energy efficiency in data centers and business-computing ecosystems. Although its focus is on data centers, the group is developing tools—such as defining models and metrics and developing energy-efficient standards and measurement methods—that could apply to embedded applications. In April, the Green Grid announced collaborations with the U.S. Environmental Protection Agency (EPA) and the Storage Networking Industry Association (SNIA) to accelerate the adoption of best practices for energy efficiency in governmental agencies and the private sector
  • Climate Savers Computing Initiative Started by Google and Intel in 2007, this is a nonprofit group of eco-conscious consumers, businesses, and conservation organizations. They promote the development, deployment, and adoption of smart technologies that can both improve the efficiency of a computer’s power delivery and reduce the energy consumed when the computer is in an inactive state. A top issue is that roughly 50% of the AC power delivered from a wall socket to a PC never actually performs any work, according to Urs Hölzle, Google fellow and senior vice president of operations. Half of that energy gets converted to heat or is dissipated in some other manner in the AC-to- DC conversion (http://www. climatesaverscomputing.org).

Energy-Efficient Processors

It wasn’t long ago that system developers had to deal with processors that topped 100 W. Basically, such processors cancelled out everyone’s best efforts to minimize board-level power consumption. Now, energy-efficient multi-core processors are operating within a saner power range like 15 to 65 W. These processors are monitoring the processing workload and using power gating to reduce average energy usage as much as 35% to 40%. “A large retailer, considering replacing its 5000 terminals with new units that operate 33% more efficiently, can reduce annual energy costs for POS terminals alone by $131,000—or nearly $1 million over the average seven-year life,” says Scott Langdoc of IDC .

“Customers worldwide are increasingly showing their preference for companies who practice social and environmental responsibility.”

System Techniques

Still, other energy-saving opportunities are available to software developers. They can dynamically adjust processor voltage and core frequency. This step also lowers fan power consumption, as the fans don’t need to spin as quickly. In fact, during periods of low demand, other system components— hard drives, network interface cards, and actuators— can potentially be throttled to save power. Embedded developers can directly manage processor power states using capabilities like Intel SpeedStep® Technology. They also can integrate other mechanisms, such as Intelligent Platform Management Interface (IPMI), to control power to other system elements. Remote management systems can power off systems automatically during off hours without employee intervention and save electricity in facilities that aren’t running 24 to 7.

Practicing Environmental Responsibility

Embedded customers are demanding action from electronics manufacturers to step up their adoption of more environmentally safe manufacturing processes. In response, semiconductor makers are manufacturing lead- and halogen-free products by replacing these toxic materials with new, earth-friendly compounds, such as metal hydroxides for flame retardation.

Furthering environmental responsibility, the IBM Retail Green Initiative develops conservation-oriented technology solutions that enable retailers to meet their ecological goals. “Our objective is to help retailers better position themselves with consumers, who increasingly value companies that are working to minimize their impact on the planet,” says Steven Ladwig, general manager of IBM Retail Store Solutions. For example, IBM and Intel are working together to design cost-effective, green retail solutions with eco-friendly features and support “sustainability” through productlongevity and material-reuse programs. One example is the IBM SurePOS 700 Series (see Figure 2). This family of point-of-sale (POS) systems reduces energy consumption by as much as 30% and carries service life cycles up to seven years.

Good Corporate Citizens

Going green is a worldwide movement and more attention is being paid to the energy efficiency of computing systems. In fact, more and more companies are making their environmental initiatives public. “Retailers are proactively informing customers about their green efforts. Tesco, the world’s third-biggest retailer, recently had a press release announcing plans to measure and publish its total direct carbon footprint as part of its commitment to tackle climate change,” says Alan Outlaw, corporate director of SMB, IBM Retail Store Solutions.

Figure 2. The SurePOS 700 family of point-of-sale systems promises to reduce energy consumption while increasing product longevity.

 

Going green is a worldwide movement and more attention is being paid to the energy efficiency of computing systems. In fact, more and more companies are making their environmental initiatives public. “Retailers are proactively informing customers about their green efforts. Tesco, the world’s third-biggest retailer, recently had a press release announcing plans to measure and publish its total direct carbon footprint as part of its commitment to tackle climate change,” says Alan Outlaw, corporate director of SMB, IBM Retail Store Solutions.