Active Mode Discussion Chris Calwell Ecos Consulting

Summary of NRDC/Ecos Research Process Reviewed independent monitor research from DisplaySearch, IDC, Europeans, and others Met with monitor manufacturers at COMDEX, CES, DisplaySearch, and one-on-one Analyzed self-reported data from manufacturers in STAR database Independently measured monitor power use Compared data with LBNL, ADL studies Made recommendations to EPA. EPA weighed them with others and created draft specification.

What Does The Term “Energy Efficient Monitor” Mean? Efficiency = Useful Output or Service Provided / Total Energy Input Useful output or service could be diagonal inches of screen size, square inches of screen size, or total pixels displayed Monitor not displaying information (providing useful output) in sleep or standby modes, so minimize power use at those times to achieve high overall efficiency Can account for all energy use in all three modes separately or with a duty cycle E NERGY S TAR seeks to recognize top 25% efficiency

Estimated Annual Energy Use for CRTs and LCDs

The Advantages of Pixels/Watt Pixels/watt approach has a number of key advantages: More technology neutral – avoids difference between viewable screen size and total Screen area (square inches) unknown to consumers Credits CRTs for their present resolution advantage, yet allows for very high resolution options like IBM’s new 9.1 million pixel LCD Emphasizes display quality over physical size Avoids difficulty of trying to estimate a representative “duty cycle” for all monitors Simple, like lumens/watt (lighting) or CFM/watt (fans). Can also be characterized as watts/megapixel

Effect of Resolution and Monitor Type on Active Power Consumption for Monitors 17” and Less

Effect of Resolution and Monitor Type on Active Power Consumption for Monitors Greater than 17”

Effect of Resolution and Monitor Type on Active Power Consumption

Applying Active Power Spec to Standard Resolutions ResolutionCategoryTotal PixelsMaximum Power Use 640 x 480VGA307,20037 watts 800 x 600SVGA480,00040 watts 1024 x 768XGA786,43246 watts 1280 x 1024SXGA1,310,72057 watts 1600 x 1200UXGA1,920,00069 watts 1800 x 14402,592,00082 watts 2048 x 15363,145,72893 watts

Need for Consistent Measurement STAR database contains self-reported data from manufacturers Not all monitors measured under identical conditions in active or “on” mode Depending on user settings and image displayed, CRT power variations can be +/- 30%. LCD variations can be +/- 50%. E NERGY S TAR has helped develop common test methods to the ventilation and lighting industries – may be able to bring standardization to monitor measurements as well.

Effects of User Settings on Power for a 21” CRT Monitor

Effects of User Settings on Power for a 17” LCD Monitor

Comparing the Proposed Specification to Compaq’s Self-Reported Data

Key Market Research Findings Laptops were first major market for LCD technology; Desktops now shifting decisively from CRTs to LCDs LCDs provide size, weight, comfort, clarity, and energy advantages to users. Even better technologies (OLEDs, others) coming soon LCDs are often more profitable for manufacturers to sell (CRTs have become a commodity) Presently hard to market LCDs on an energy efficiency basis – virtually all monitors have E NERGY S TAR ® label and no standardized power use information is shown on packaging Need for a new specification and test method to fairly compare monitors on total energy use in active, sleep and off modes.

Entry Level (<$1,000) Computer Systems Now Commonly Offer LCD Screens