Energy star compliance is measured at the system level, this includes the power supply losses and only qualifies the top 25% of products on the market. The EPA is clear that the Energy Star label is voluntary but many company find it quite advantageous to comply with Energy Star.
The Energy Star requirements measure the system Idle power (SO), system sleep power (S3), and the system standby power. The requirements do distinguish between integrated graphics or discreet graphics. Category A with integrated graphics requires a power draw of 14 watts or less. Category B with discrete graphics requires a power draw of 22 watts or less at idle. At sleep it is 1.7 watts or less and 2.4 watts or less. Standby must be less than 1 watt and 1.7 watts or less of power draw.
The next Energy Star v.5.0 will have a goal of approximately 25% reduction of power usage compared to the current 4.0 spec. The EPA tried to design the EECoMark standard which would take into account the annualized measure of energy consumption but that spec isn't stable right now and so there will be a revision of the 4.0 standards.
Energy Star has a separate specification for power supplies. The European Union has its own program for power regulations called EuP which covers all kinds of consumer electronics with a focus on standby and off states usage of power. Lot6 regulations covers all electrical devices and will be effective in 2009. This is a mandatory requirement that bars market access if the electronic device does not meet this requirement.
Power regulations are becoming more standard throughout the world with many countries passing energy regulations with an expectation that they will increase in scope and compliance with them is essential to business success. This means that the designers of notebooks need to begin to look at some additional methods of saving energy. One of the worst offenders is the USB as it is not well-behaved from a power management perspective because they poll the memory every on millisecond even when idle.
He recommends using PCIe or side band to deal with the USB. The audio codec is often not been managed from a power perspective because the loss of quality is fairly significant due to artifacts. There is a new codec, hda015-b compliant codecs, can enter the d3 state in idle conditions and it can be entered/exited dynamically. External graphics have traditionally not have power management and the dissipate multiple watts in idle conditions. There is an initiative toward switchable graphics which would allow a lower power usage when the graphics load is lower.
Voltage regulators and power supplies use 16% to 20% of the platform's use of idle power. This is because they're designed to be efficient at high loads so at low loads they are enormously wasteful. This is a difficult balance to achieve. In short, it is a small box to fit into as the regulations become more stringent. There are some easy methods of reducing power for the first round of compliance but there is a great need for some innovation in the area of ethernet, memory, voltage regulators and power supplies to reduce the power usage. X |