# Presentation: 205145

## 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
- ENERGY STAR 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

| Resolution | Category | Total Pixels | Maximum Power Use |
| --- | --- | --- | --- |
| 640 x 480 | VGA | 307,200 | 37 watts |
| 800 x 600 | SVGA | 480,000 | 40 watts |
| 1024 x 768 | XGA | 786,432 | 46 watts |
| 1280 x 1024 | SXGA | 1,310,720 | 57 watts |
| 1600 x 1200 | UXGA | 1,920,000 | 69 watts |
| 1800 x 1440 |  | 2,592,000 | 82 watts |
| 2048 x 1536 |  | 3,145,728 | 93 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%.
- ENERGY STAR 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 ENERGY STAR® 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

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