EcoDesign for TV Displays
The world population is still growing, while consumers in emerging markets are becoming more affluent and able to purchase electronic products such as televisions. The resulting environmental impact needs to be assessed for entire product life cycles. In televisions, displays dominate the environmental profile. Therefore, their performance is continuously monitored with Philips's EcoDesign approach.
by Kees (Cornelis) Teunissen and Leendert Jan de Olde
SOCIETAL TRENDS and environmental consciousness, in combination with emerging legislation, are requiring manufacturers of consumer-electronics goods to address ever more challenging conditions in which to do business. Sustainability and eco-design have become established phenomena in the design considerations of manufacturers, including television manufacturers. Successful industries and companies will effectively discover and use the opportunities these challenges pose. A level playing field is created by the implementation of rules and regulations, but is only guaranteed through verification by authorities. The latter is essential to support energy-saving and sustainability-related innovations in the highly competitive consumer- electronics market. In this article, the authors describe which eco-design challenges the display industry faces and how they offer opportunities for innovation and growth.
Global Trends and Challenges
The world's rapid population growth, as shown in Fig. 1,1 in combination with increasingly affluent consumers in markets such as Asia, will over the next decades place ever more severe stresses on the world's resources, including raw materials, water, and energy.
Fig. 1: In most parts of the world, with the exception of Europe, the population is expected to increase through 2050.
Global Footprint Network's latest data2 show that humanity is currently consuming resources and producing waste (such as CO2emissions) at rates for which the ecological services of nearly two planets would be required just in order to meet demand through the early 2030s. Maintaining this rate of consumption could cause major eco-system collapses well before that threshold is reached. In 2006, the Energy Saving Trust predicted that by 2010 consumer electronics would become the largest single sector of consumer electricity consumption.3 Governments are already acting on these developments with legislative measures designed to reduce energy consumption and overall use of resources. The entire industrial value chain will have to proactively address this situation while also continuing to create value from their activities.
In the television industry, new technologies such as plasma-display panels (PDPs) and liquid-crystal displays (LCDs) not only have enabled larger TVs, but have also turned them into "must-have" products. In particular, the rise in popularity of large plasma TVs was at one point expected to result in a major contribution to the energy consumption of households, as their average on-mode power consumption was measured to be up to four times higher than that of a normal-sized cathode-ray-tube CRT) TV.3 In the meantime, these technologies have become more energy-efficient, but some still consume more energy than the same-sized CRT-based televisions.
TV-broadcast services are still a major source of information delivery. In 2008, TV watching increased to about 3.5 hours per day in Europe and 4.6 hours per day in the U.S.4 Now, Internet-connected TVs are emerging, potentially increasing TV-on times and consequently the consumption of electricity. If not properly managed, the combination of large-sized televisions with increasing power-on time will result in a significant increase in electricity consumption around the world.
Environmentally Conscious Design
Environmentally conscious design or eco-design aims to improve the environmental performance of a product when viewed over its total environmental lifecycle. This requires data to be assessed from the mining of raw materials used to make the display until its end-of-life phase. The products' short lifecycle and the scarcity of resources used to make the products urge a re-evaluation of recycling at the last stage. Such an evaluation was published by Rose and Stevels5 in 2001 for a set of consumer-electronics products, including CRT-based televisions, but the study shall be redone for televisions based on the newer display technologies.
In 2009, international standard IEC 62430, "Environmentally conscious design for electrical and electronic products," 6 was published. This standard provides a set of fundamental requirements for the process of environmentally conscious design and can be used as a base reference to ensure consistency throughout the electrotechnical sector.
Environmental Design at Philips
The environmental lifecycle approach to products has been in use at Royal Philips Electronics since the early 1990s. The company has created an environmental impact database and maintained it with regard to both external and internal sources. However, interpretation of lifecycle data can be difficult and for that reason it is not the most appropriate type of information to convey to product designers, nor to end users. Therefore, Philips uses "Green Focal Areas" that capture the main life-cycle aspects: energy, hazardous substances, weight, packaging and transport, and recycling and disposal. Analyzing not only Philips products, but also competitors' products in an environmental benchmark, and formulating improvement actions in terms of the green focal areas, has resulted in target-oriented actions. As a result, the percentage of Philips Green Product sales increased from 20% in 2007 to 31% in 2009, whereas 90% of the Philips TV portfolio has been awarded the EU Ecolabel after verification that the products met the EU's environmental and performance standards.7 In September 2010, Philips launched its Econova LED TV (Fig. 2). Based on its "holistic approach to eco-design," Philips received the European Green TV EISA award 2010-2011 for this television.8 In addition, the Dow Jones Sustainability Indexes Review 20109 identified Philips Electronics as a global sustainability leader for the Supersector "Personal & Household Goods 2010-2011."
Fig. 2: The Philips Econova LED TV, 42PFL6805, features an LCD with an edge-lit LED-based backlight.
Over the past decade, many world regions have proactively started to accelerate their legislative activities in the environmental field. European directive 2002/96/EC on waste electrical and electronic equipment (WEEE)10 ensures that products are being recovered and recycled, while directive 2002/95/EC on the restriction of the use of certain hazardous substances in electrical and electronic equipment (RoHS)11 aims to limit environmental impact when the products have reached the end of their life. Display makers are urged to proactively meet the targets, as outlined in these directives, such that TV manufacturers can in turn meet their increasingly strict "green" requirements.
The amount of energy consumed by products during their life is also now being regulated. In the year 2005, Europe published the framework directive 2005/32/EC12 on eco-design of energy-using products (EuP). Under the EuP framework, a number of implementing measures were and are currently being developed that will address various product categories; some measures will even address specific aspects of product energy use, such as standby, independent of product categories. Products unable to meet the requirements for a category will not be allowed for sale on the European market; i.e., the 27 independent sovereign European countries. One of the implementing measures addresses televisions, whereas another addresses computers and their monitors.
Commission regulation (EC) No. 642/200913 addresses eco-design requirements for televisions. Among other details, it sets limits on standby and on-mode power consumption of a television. For the on-mode power consumption, the following requirements apply:
As of 20 August 2010, the on-mode power consumption of a television with visible screen area A, expressed in dm2, shall not exceed the following limits:
• Full-HD resolution:
20 W + A x 1.12 x 4.3224 W/dm2 (1)
• All other resolutions:
20 W + A x 1.00 x 4.3224 W/dm2 (2)
From 1 April 2012, the on-mode power consumption of a television with visible screen area A, expressed in dm2, shall not exceed the following limits (for an example, see Fig. 3):
Fig. 3: EC commission regulation13 sets limits on the maximum on-mode power consumption for full-HD televisions as a function of diagonal screen size, Eqs. (1) and (3).
• All resolutions:
16 W + A x 3.4579 W/dm2 (3)
Televisions may have several modes that are preset by the manufacturer. The maximum allowed power consumption, but also the energy label, will be based on the energy use in the TV manufacturer's recommended "home-mode." To avoid televisions being put on the market with an unrealistically low luminance, i.e., low power, in the "home-mode," a minimum luminance ratio of 65%, between the luminance measured in the brightest on-mode offered by the TV and the actual luminance in the "home-mode," has been defined. The 65% value is based on a market study performed in the UK at the end of 2008.14 The downside of this approach is that it does not reflect or anticipate the expected improvements in energy efficiency and the brighter settings that are achievable as a result of more efficient displays. Additionally, it does not take into account that, by the end of 2008, most televisions were tuned to optimize picture quality instead of balancing picture quality with power consumption. Finally, it shall be noted that the test patterns to measure the actual luminance ratio have not yet been defined.
Next to the EcoDesign requirements, a labeling scheme that has proven to be successful in guiding consumers toward more energy-efficient white goods and home appliances sold in the EU market is currently under debate.15 A political agreement has been reached that the existing A–G scale will see an expansion with A+, A++, and A+++ classes. (For an example, see Fig. 4.)
Fig. 4: The above chart shows the power limits for the proposed energy efficiency classes for televisions as a function of diagonal screen size, derived from draft EU commission delegated regulation.15
Periodic rescaling when more than a third of products reach the A++ or A+++ classes is foreseen. The energy labeling implementation measures for TVs are expected to be published by the end of 2010 at the earliest and could be relevant for products released on the European market 1 year after publication.
TV Power Consumption
In order to estimate the annual energy usage of TVs, IEC standard 6208716 was revised to better reflect actual power draw during normal home TV-viewing conditions. A 10-minute dynamic broadcast-content video signal was created that contains various television fragments that represent a global average of what people watch on their TVs. The method of measuring the on-mode power consumption is rather straightforward; after an initial stabilization period, a meter will record the energy consumed during the playing of the 10-minute video, with all picture settings in the default, manufacturer recommended values. This international standard is now widely used to measure the on-mode power consumption for televisions.
Energy use in a TV not only depends on a vast amount of technological factors, but also on system-level implementations. The main technological factors are the type of display technology (CRT, LCD, PDP, and OLED), efficiency of the light generation, and power-supply efficiency. System-level aspects related to energy use are identified by set architecture, features offered, ancillary instruments (e.g., light sensors), software algorithms, and default picture settings. IEC standard 62087 provides means to measure the power savings related to these features.
All flat-panel-display technologies are targeting reduction in energy usage to meet eco-design requirements and "Green" labels. LCD panels, dominant in both TV and monitor applications, are moving toward better efficiency through the use of technologies such as better optical films17 and LED applications allowing localized dimming.18 In the meantime, their energy efficiency has surpassed that of the CRT (see Fig. 5 for an example).
Energy efficiency measures in display technology need to go hand-in-hand with measures of reducing the power consumption of TV sets. Automatic adjustment of the display luminance as a function of ambient illumination is one example for reducing power. Another is video-based backlight dimming.
On the other hand, pushing innovations that are aimed at higher numbers in the product specification may have a negative impact on the TV power draw.19 An example is the number of addressable display pixels. When the display has more pixels than the human eye can resolve at a given viewing distance, more power is consumed (smaller cells are typically less efficient) for the same perceived image quality. Another example is extending the display's color gamut beyond the gamut transmitted in the video broadcast material. Without a clear strategy to use the extended color space, this could result in less-energy-efficient displays without obvious benefits for the end-users. Therefore, we encourage the display industry to carefully consider the environmental impact when pushing technological innovations.
Level Playing Field
TV manufacturers operate in a highly competitive market and therefore legal requirements should support a level playing field. For products that are targeting the same consumers, the same energy-efficiency requirements should apply regardless of the technology that is being used. In most countries where legal requirements are established, this is ensured but there are exceptions, such as in China, where minimum requirements and a mandatory energy label for television are expected to enter into force in the short term.20 The standards are established as such that separate less-stringent requirements are set for televisions with plasma displays as compared to liquid-crystal displays. This not only leads to misinformation for consumers when comparing power consumption of televisions, but also disrupts the market as some TV manufacturers are forced to make a bigger investment to achieve the same grade on an energy label.
Governments not only play a vital role in establishing a level playing field through legislation, but must also be active in enforcement through verification. For example, consumers have become more conscious of energy efficiency and demand environmentally friendly products as one of the ways to reduce their electricity bills. Energy labels provide energy-efficiency information in a transparent way and have already proven to be successful in guiding consumers toward more energy-efficient products. When consumers purchase a new television, computer, or household appliance, they need to be confident that the information provided on the label is correct, meaning accurate and measured in compliance with the applicable legislation and standards. A study published in November 200921 and performed on behalf of the UK's Government Department for Environment, Food, and Rural Affairs (DEFRA), showed that 16 out of 24 washer driers tested did not perform in accordance with all declarations on their labels. Furthermore, four of the washer driers tested were unable to dry to the required level, which means that even where consumers have bought an apparently energy-efficient appliance, the need to dry clothes for longer periods of time may result in higher energy use than suggested on the label. Verification by authorities contributes to the credibility of the energy label and also assures that brands, willing to invest in sustainability, are rewarded for their energy-efficiency-related innovations and investments.
The demand for large-sized televisions is increasing. Global trends including the environmental consciousness of consumers and emerging legislation in all world regions continuously impose challenges for all consumer-electronics companies, such as TV manufacturers, to live up to. Consumers are increasingly sensitive to energy consumption because of the already existing labeling in the white goods sector and increasing legislation to ban incandescent light bulbs. Tools such as energy labeling for television products will provide relevant information more transparently. Legislation, scarcity of natural resources, and prevention of massive landfill problems demand recyclable products, which in turn require components and materials free of banned and hazardous substances. Consequently, the display industry needs not only to proactively contribute to meet legislative measures, but also provide transparency in used materials and underpin claimed energy efficiency with established measurement standards. A level playing field must be established through legislation, but verification by authorities is essential to assure that brands willing to invest in sustainability are rewarded for their energy-efficiency-related innovations and investments. Some innovations, such as LEDs and polarization recycling optical stacks in LCDs, already contribute to reducing energy bills. Only through continuous incremental and breakthrough innovations, particularly in the display industry, can TV manufacturers contribute toward reducing the environmental impact of TVs while at the same time capturing opportunities to continue doing business.
2"A time for change," Global Footprint Network annual report (2009),http://www.footprintnetwork.org/images/uploads/Global_Footprint_Network_2009_Annual_Report.pdf.
3Source: UK Energy Saving Trust, "Rise of the Machines: A review of energy using products in the home from the 1970s to today" (June 2006).
5C. M. Rose and A. Stevels, "Metrics for end-of-life strategies (ELSEIM)," Proceedings of the 2001 IEEE International Symposium on Electronics and the Environment, 100–105 (2001).
6IEC-62430, Edition 1.0, "Environmentally conscious design for electrical and electronic products," (February 2009).
7Philips Annual Report (2009).
9http://www.sustainability-index.com/ djsi_pdf/news/PressReleases/DJSI_Press Release_100909_Review10.pdf.
10Directive 2002/96/EC of the European Parliament and of the Council of 27 January 2003 on waste electrical and electronic equipment (WEEE) (2003).
11Directive 2002/95/EC of the European Parliament and of the Council of 27 January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment (2003).
12Directive 2005/32/EC of the European Parliament and of the Council of 6 July 2005 establishing a framework for the setting of eco-design requirements for energy-using products and amending Council Directive 92/42/EEC and Directives 96/57/EC and 2000/55/EC of the European Parliament and of the Council," Official Journal of the European Union (2005).
13Commission Regulation (EC) No. 642/2009 of 22 July 2009 implementing Directive 2005/32/EC of the European Parliament and of the Council with regard to ecodesign requirements for televisions (2009).
15Draft Commission Delegated Regulation (EU) No. …/.. of [...] implementing Directive 2010/30/EU of the European Parliament and of the Council with regard to energy labeling of televisions (September 2010).
16IEC-62087, Edition 2.0, "Methods of measurement for the power consumption of audio, video and related equipment" (October 2008).
17SID 2009 Seminar Notes on "Optical Films for LCD Backlights," by Gary Boyd, 3M Optical Systems Division (June 2009).
18H. Groot Hulze and P. de Greef, "Power Savings by Local Dimming on a LCD Panel with Side Lit Backlight," SID Symposium Digest40, 749-752 (2009).
19C. Teunissen and C. van der Klauw, "Display Technology Trends Perceived from a Consumer (Electronics) Point of View," Proc. IDW '07, 2271-2274 (2007).
20National Standard of the People's Republic of China, "Minimum allowable values of energy efficiency and energy efficiency grades for flat panel televisions" (Manuscript submitted for approval) (December 2009).
21DEFRA, press release Ref: 278/09, November 30th 2009, "Energy labeling tested by DEFRA." •