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Environmental Screening and Evaluation of Energy-using Products (EuP) Final Report

5 Personal computers (desktops and portables) & monitors (Lot 3)

5.1 Background

The Preparatory study for the Personal Computers (desktops & laptops) and computer monitors (Lot 3) uses the following product definition for personal computers:

A device which performs logical operations and processes data. Personal computers are composed of, at a minimum: (1) a central processing unit (CPU) to perform operations; and (2) user input devices such as a keyboard, mouse, digitizer or game controller.

For the purposes of this study, personal computers include both stationary and portable units, including desktop computers, integrated computers, notebook computers and tablet PCs. For further definitions of these computer categories, the Energy Star definitions are applicable.

Note that workstations, desktop-derived, mid-range and large servers, game consoles, thin clients/blade PCs, handhelds and PDAs are not included in this product definition of personal computers, and will therefore not be covered by this study [IVF2007].

According to an Eco-design study on Personal Computers and Monitors [ECC2006] in 2005 there were about 105 millions desktop, 24 millions laptops and 104 million monitors (of which 47 were flat panel) installed in household in the EU-25. As the short life-time of the computers is very significant for the overall results, improvement options regarding life-time extension are important (designing computers for easy change of important parts like the memory, the hard disk etc.).

The Preparatory study for the Personal Computers estimates the number of personal computers and laptops in use world to approach half a billion by 2020

Figure 5.1 Estimated installed base of personal computers in 2020 (Source: [IVF2007])

Figure 5.1 Estimated installed base of personal computers in 2020 (Source: [IVF2007])

5.2 Environmental screening based on the Ecoinvent database

The environmental screening for Personal Computers and Computer monitors is based on the Ecoinvent processes:

  • Use, computer, desktop with CRT monitor, active mode
  • Use, computer, desktop with LCD monitor, active mode
  • Use, computer, laptop, active mode
  • Desktop computer, without screen, at plant
  • Laptop computer, at plant
  • CRT screen, 17 inches, at plant
  • LCD flat screen, 17 inches, at plant
  • Keyboard, standard version, at plant
  • Mouse device, optical, with cable, at plant

Figure 5.2, figure 5.3 and figure 5.4 show the contributions to the environmental impacts from the use of computers, i.e. the processes “Use, computer, desktop with CRT monitor, active mode”, “Use, computer, desktop with LCD monitor, active mode” and “Use, computer, laptop, active mode“. These processes include the computer, the screen, the keyboard, the mouse, transport from production to consumer and the electricity consumption during the active use of the computer. It has deliberately been chosen to show the results of the “active mode” process in contrary to the “standby-mode” or “off-mode”-processes, which is also modelled by Ecoinvent, in order to give the impression of the relative significance of the electricity consumption compared to the hardware parts.

It can be seen from the figures that when using a computer (i.e. in the “active mode”), the electricity consumption is the main contributor to all the environmental impacts, but for mineral extraction. This is not a surprise.

However, what is interesting is that even when including the energy consumption during use, the production of the hardware is significant for the overall environmental impacts. As a computer is not in “active mode” all 24 hours a day (but also “stand by” and turned off) the significance of the electricity consumptions is considerably lower.

The relative contribution from the hardware parts is highly dependant on the lifetime of the hardware. Ecoinvent has assumed a lifetime of the computers to four years, which seems reasonable.

Click here to see: Figure 5.2 Environmental impacts from the use of a desktop computer with a CRT monitor (in active mode), including keyboard and mouse.

Click here to see: Figure 5.3 Environmental impacts from the use of a desktop computer a LCD monitor (in active mode), including keyboard and mouse.

Click here to see: Figure 5.4 Environmental impacts from the use of a laptop computer (in active mode).

Click here to see: Figure 5.5 Environmental impacts from the use of a desktop computer with a CRT monitor including keyboard and mouse. Contributions from the electricity consumption during use have been omitted.

Click here to see: Figure 5.6 Environmental impacts from the use of a desktop computer with a LCD monitor including keyboard and mouse. Contributions from the electricity consumption during use have been omitted.

Figure 5.5 and Figure 5.6 show the same as Figure 5.2 and figure 5.3 for a CRT and a LCD monitor respectively, but without the electricity consumption during use. From these it can be seen that the most significant contributions come from the computer and the screen.

Figure 5.7, Figure 5.8, Figure 5.9, Figure 5.10 and Figure 5.11 show analysis of contributions from the production of a desktop computer (without screen), a laptop computer, a CRT screen (17 inches), a LCD flat screen (17 inches), a keyboard (standard version) and a mouse, all at plant.

From these figures, we can see that for the production of a desktop computer, the parts that mainly contribute to the environmental impacts are:

  • The printed wiring board (and the Integrated Circuit to this, and the wafer used for the Integrated Circuit).
  • The power supply unit
  • The CD-ROM / DVD-ROM drive
  • Steel production

Figure 5.7 Environmental impacts from production of a desktop computer.

Figure 5.7 Environmental impacts from production of a desktop computer.

Click here to see: Figure 5.8 Environmental impacts from production of a CRT monitor.

Figure 5.9 Environmental impacts from the production of a LCD flat screen.

Figure 5.9 Environmental impacts from the production of a LCD flat screen.

Figure 5.10 Environmental impacts from the production of a keyboard.

Figure 5.10 Environmental impacts from the production of a keyboard.

Figure 5.11 Environmental impacts from production of a mouse.

Figure 5.11 Environmental impacts from production of a mouse.

When analysing the contributions from the desktop computer, the main contributions to:

  • Global warming, respiratory inorganics, respiratory organics, photochemical ozone (vegetation), terrestrial eutrophication, mainly derive from energy producing processes, especially to the energy consumption for the production of the printed wiring board and the parts for this and for the power supply unit. Also blaster, production of clinker and sinter (iron) has significance for these environmental impacts.
  • Ozone layer depletion comes from the production of tetrafluoroethylene, trichloromethane, chlorodifluoromethane, for the production of wafer and from crude oil production.
  • Acidification mainly comes from production of primary palladium, powder coating of steel, blasting, operation of transoceanic freight ships, primary copper production and energy production.
  • Aquatic eutrophication mainly comes from production of ultrapure water, which is used in the production of the integrated circuit and the printed wiring board.
  • Human toxicity (carcinogens) mainly comes from steel production, production of primary aluminium, production of primary copper and natural gas production. The contributions mainly come from aromatic hydrocarbons, arsenic, dioxins, and PAHs (polycyclic aromatic hydrocarbons).
  • Human toxicity (non-carcinogens) mainly comes from the processes: disposal of hydrated cement to landfill, treatment of wafer fabrication effluent to wastewater treatment, production of primary copper, and disposal of residues from the desktop computer
  • Ecotoxicity, aquatic comes from gold production (emissions of Copper, Zinc, Nickel, Mercury, Chromium, Arsenic, Lead and Cadmium).
  • Ecotoxicity, terrestrial comes from production of primary copper, primary zinc, and production of the printed wiring board and steel production (emissions of Copper, Zinc, Nickel, Mercury, Chromium, Lead, Arsenic, Cadmium and Cobalt)
  • Nature occupation mainly comes from disposal of sulfidic and non-sulfidic tailings in non-ferrous metal extraction and gold mining.

For the CRT-screen, the main environmental impacts come from the production of the cathode-ray-tube and printed wiring board.

For the LCD-screen, the main environmental impacts come from the production of the LCD module and assembly of the LCD screen, and, again the printed wiring board.

For the keyboard, the main environmental impacts mainly come from the Printed wiring board. Zinc coating contributes to ecotoxicity, and the production of acrylonitrile-butadiene-styrene copolymer (ABS) contributes especially to human toxicity. Disposal of the keyboard contributes to human toxicity and ecotoxicity.

For the mouse, the main environmental impacts come from the production of the printed wiring board.

5.3 Ecolabel requirements

In the European Ecolabelling programme there is a criteria document for Ecolabelling of portable computers and a criteria document for personal computers ([EC2005a] and [EC2005b]). Some of the focus points of the European Ecolabel criteria documents for computers are:

  • Energy consumption in “sleep state” and “off-mode”
  • Energy consumption by the power supply when it is connected to the electricity supply but is not connected to the computer (for potable computers)
  • Electromagnetic emissions
  • The computers shall be designed for lifetime extension (the memory, the hard disk (and if available the CD drive and the DVD drive) shall easily accessible so that they can be changed
  • A maximum mercury content of liquid crystal display (LCD) monitor
  • The computer shall be designed for facilitate recycling (easy to disassemble).
  • Plastic parts shall have no lead or cadmium intentionally added
  • Plastic parts shall not contain poly-brominated biphenyl (PBB) or poly-brominated diphenyl ether (PBDE) flame retardants
  • Restrictions regarding flame retardants substances
  • Maximum level for mercury, cadmium and lead in batteries

The Nordic Ecolabelling system also contains criteria for personal computers. The criteria focus on following aspects: power consumption, design (upgradeability and disassembling), plastics and their additives, e.g. flame retardants, heavy metals, recycling of discarded products, performance such as noise level, ergonomics and electrical, and magnetic fields. Some of the focus points of the Nordic Ecolabel criteria documents for personal computers are [NE2007b]:

  • The computer system unit shall meet the Energy Star configuration requirements that enable energy efficiency modes.
  • Desktop computers shall support the ACPI S3 sleep state (suspend to RAM) to allow a power consumption of no more than 4.0 watts and the off-mode power consumption shall be no more than 2.0 watts.
  • The monitor shall have a sleep mode power consumption of no more than 2.0 watts and an off-mode power consumption of no more than 1.0 watt.
  • Portable computers shall support the ACPI S3 sleep state (suspend to RAM) to allow an energy consumption of no more than 3.0 watts. The power supply of the portable computer shall have a maximum consumption of no more than 0.75 watt when it is connected to the electricity supply but is not connected to the computer.
  • System units, displays, keyboards and portable computers must be designed in such a way that disassembling is possible. The substances, preparations and components listed in Annex II of WEEE Directive (2002/96/EC) must be removable. 90 wt% of plastics and metals in the housing and chassis must be technically suitable for material recovery.
  • The system unit of a stationary computer must have a modular design. The user shall be able to replace the modules without the use of special tools and it shall be possible to upgrade the computer.
  • The housing and chassis must not contain chlorine-based plastics. Large plastic parts (>25 g) must not be painted or metallized (this requirement does not apply to portable computers).
  • Plastic parts must not contain halogenated flame retardants. The use of flame retardants that can be assigned one or more risk phrases at the time of application, in accordance with EU chemical legislation, is prohibited. However, some parts are exempted.
  • Materials may not contain cadmium, lead or mercury. The exemptions are the same as in Directive 2002/95/EC (RoHS).
  • With the exception of technically unavoidable impurities, batteries and accumulators must not contain any lead, cadmium or mercury. Such impurities must not exceed the limit values specified in the EU Battery Directives (91/157/EEC and 98/101/EEC).

TCO is a quality and environmental labelling system, the purpose of which is to influence the development of products to ensure optimum user-friendliness and minimum impact on the environment. Desktops are assessed in the areas of ergonomics, emissions, energy, and ecology. Desktops are certified according to TCO’99:

  • A flicker-free image with good brightness and good contrast.
  • Considerable reduction of magnetic and electrical fields.
  • Low noise levels.
  • Low energy consumption for reduced environmental impact.
  • The energy saving function provides a better indoor climate through reduced heat emission, thus retaining air humidity.
  • Reduced emission of brominated flame-retardants, mercury, cadmium, lead and hexavalent chromium into the environment (complies with the RoHS Directive).
  • Recycling preparations facilitate material recycling.
  • Manufacturer ISO 14001 certified.
  • Environmental characteristics of the flame-retardants used in the product have been tested.
  • Information on where the computer can be turned in for recycling.

TCO'05 provides criteria for portable computers:

  • High visual ergonomic requirements for the display resulting in high image quality.
  • Considerable reduction of magnetic and electrical fields.
  • Low noise levels.
  • Low energy consumption for reduced environmental impact.
  • The energy-saving function provides a better indoor climate through reduced heat emission, thus maintaining air humidity.
  • Reduced emission of brominated flame-retardants, mercury, cadmium, lead, and hexavalent chromium into the environment (complies with the RoHS Directive).
  • Recycling preparations facilitate material recycling.
  • Manufacturer ISO14001 certified.
  • Environmental characteristics of the flame-retardants used in the product have been tested.
  • Information on where the computer can be turned in for recycling.

5.4 Technology and market trends

Practically all personal computers for office and private use are connected to the internet, which is a major driver for the purchase and use of computers. It is also a major driver for renewal and upgrade of hardware.

According to OECD; Denmark is positioned as number four in the world in terms of computers connected to the internet with almost 80 per cent of all computers connected [OECD2007]:

Figure 5.12 ICT usage in households and by individuals, April 2007[OECD2007].

Figure 5.12 ICT usage in households and by individuals, April 2007[OECD2007].

Connection to media and rich information on the Internet require fast transmission of digital content. Broadband is thus one of the fastest among new communication technologies in Europe. The total number of broadband lines in the EU has quadrupled in just three years. In October 2005, 80% of broadband subscribers in the 25 EU Member States used DSL to connect to broadband Internet. Cable modems currently account for about 16% of all broadband connections in the EU-25 [Com2006]. In January 2006, broadband reached almost 60 million subscriber lines in the EU-25 and had a penetration rate of about 25% of households. Growth in broadband is mainly market-driven. Broadband growth is uneven across Member States. The best performers on broadband penetration have been and are the Denmark and the Netherlands.

Click here to see: Figure 5.13 OECD Broadband Portal [www.oecd.org/sti/ict/broadband].

Current projections show that the predicted uptake of the two key broadband WANs (wide area communication networks), DSL (digital subscriber line) and digital cable, will have a large potential impact on European household energy consumption. Even with the unlikely application of best practice in energy efficiency for all the network and end-user hardware, a simple broadband terminal for, say, 200 million EU households by 2010 would increase annual domestic electricity demand by an estimated 6,6 TWh. This could effectively be doubled by associated LAN equipment [IES2007].

Figures on energy consumption for DSL modems vary significantly. In the UK, the largest national telecommunication provider, BT, has, through energy efficient procurement policy, provided basic, self-powered external DSL modems with a 4,0W power requirement. More typical devices in the open market and supplied by some other European telecommunication groups have a power requirement of about 10 W. With the latter, up to 87 kWh per annum could be added to a household’s energy overheads. The EU added in 2005 more than 17 million new DSL subscribers in the period to reach 52.8 million – at a growth of 48% – extending its global share of the DSL subscriber market to almost 35%. Expectations are that broadband equipment will contribute to the electricity consumption of households in European Community in the near future. Depending on the penetration level, the specifications of the equipment and the requirements of the service provider, a total European consumption of up to 50 TWh per year can be estimated for the year 2015 [IES2007].

To address the issue of energy efficiency whilst avoiding competitive pressures to raise energy consumption of equipment all service providers, network operators, equipment and component manufacturers helped the European Commission to develop the Code of Conduct for Broadband equipment[¹]. The Code of Conduct sets out the basic principles to be followed by all parties involved in broadband equipment, operating in the European Community, in respect of energy efficient equipment. The Code of Conduct covers, both on the consumer side (end-use equipment) and the network side (network equipment), for services providing a two way data rate of 144kb/s or above. With the general principles and actions resulting from the implementation of the new Code of Conduct on energy consumption of broadband equipment the (maximum) electricity consumption in this sector could be limited to 25TWh per year.

The increased networking capabilities, faster bandwidth, wireless accessibility and the need for mobility has a further implication on personal computers, which could cast doubt on the longer term forecast for energy consumption of computers. When every corner of the personal and professional space is accessible via wide-bandwidth, secure networks, the need for powerful processors and mass storage in each device diminishes. The facilities provided by the network allow the user to perform massive computations on central server centres store large amount of (multimedia) data.

The user will access the server centres through simple lightweight devices with multimodal user interfaces (graphics, sound, speech, gestures, biometric authentication, etc.). A Tablet PC is a notebook or slate-shaped mobile computer, first introduced in the early 90s and popularized by Microsoft. Its touch screen or graphics tablet/screen hybrid technology allows the user to operate the computer with a stylus or digital pen, or a fingertip, instead of a keyboard or mouse. The form factor offers a more mobile way to interact with a computer. Tablet PCs are often used where normal notebooks are impractical or unwieldy, or do not provide the needed functionality. Some Tablet PC’s have keyboard (slates). Thin-client slates consist of a touch screen and an integrated wireless connection device. These units by design have limited processing power which is chiefly involved with input/output processing such as video display, network communications, audio encoding/decoding, and input capture.

Handheld Computers, PDA’s (Personal Digital Assistants) and Smart Phones are also becoming more and more used as interface devices to applications running on large servers.

The number of huge server centres operating today to server the present Internet is already impressive. Though the numbers are not publicly known, some people estimate that Google maintains over 450,000 servers located in clusters in cities around the world. The so-called Next Generation Network (NGN) will facilitate the deployment of millions of new services (entertainment, security, health) in the global networks with a corresponding exponential growth in server centres.

5.5 Conclusion

The EuP preparatory study [IVF2007] provides several specific suggestions for environmental improvements in the design and use of personal computers, such as:

  • Reducing the environmental impact from board assembly
  • Improvements in monitors for PCs
  • LED backlight for LCD monitors
  • Possibility to take the lamps out of the LCD for End of Life treatment
  • Minimizing the content of flame retardants in plastics
  • Change to renewable plastics
  • Batteries for Laptops
  • Make it easy to remove the batteries
  • Effective charging methods
  • Minimise battery aging
  • New battery chemicals (Best Not Yet Available Technology)
  • Fuel cells (Best Not Yet Available Technology)
  • Best Not Yet Available Technologies
  • OLED Displays (organic light-emitting diode)

However, when describing the improvement options, it seems that not all the suggestions mentioned above are actually included in the final recommendations.

5.5.1 Environmental impact in a system and life-cycle perspective

The main contributions to the overall environmental impacts come from the electricity consumption during use of the computer (in “active mode”), which is not a surprise. The electricity consumption is the main contributor to all the environmental impacts, but for “mineral extraction”.

However, what is interesting is that even when including the energy consumption during use, the production of the hardware is quite significant for the overall environmental impact. From the production of the hardware, it is especially the energy for the production and eco-toxicity impacts from heavy metals (arising during the extraction of materials for the components of the computers and monitors and during production of the hardware - e.g. emissions of Copper, Zinc, Nickel, Mercury, Chromium, Lead, Arsenic, Cadmium and Cobalt).

As the short life-time of the computers is very significant for the overall results, improvement options regarding life-time extension are important (designing computers for easy change of important parts like the memory, the hard disk etc.).

Design for reuse of components and recycling of materials from computers should be highly prioritised and more efforts should be devoted to automated and efficient disassembly and recovery technologies. Due to the short life-time of computers and monitors, the end of life (disposal / dismantling for recycling) of computers and monitors is very significant for the overall environmental impacts of the products.

Waste handling and incorrect recycling methods especially in developing countries constitutes a significant environmental problem. Incorrect recycling of computers might lead to huge environmental impacts, for example when second hand computers are collected and sent to developing countries to be “recycled” – some are repaired and reused, but a significant amount ends up as rubbish. Scientists have documented serious environmental contamination with potentially toxic metals from crude e-waste recycling in a village located in southeast China and in Mexico. Recycling methods used in family-run workshops could pose a serious health risk to residents of the area through ingestion and inhalation of contaminated dust [SD2008].

5.5.2 Environmental perspective from new technologies

The EuP preparatory study [IVF2007] lists a few effective designs that can be deployed to achieve a significant reduction of energy consumption in the use phase:

The processor in a 2005 desktop computer takes roughly 40 % of the energy. In a laptop, which also has a LCD-screen, the processor uses around 20 % of the energy. Dual core technology, offers 60 % savings in processor energy use.

One method of reducing the power consumption in a desktop is to reduce the intensity of the processor e.g. by reducing clock frequency or voltage when the need for capacity is reduced. This is often applied in laptops in order to increase the battery time. As much as 40 % of the power consumption of the processor can be saved if adaptive intensity is used. By using a switched power supply designed to high standard, the power supply efficiency can be increased from currently 65-70 % (2005) to 80 % or even 90 %. It should be noted that Energy Star 4.0 requires “80-plus” power supplies.

However, the longer term trend towards tablet PCs and handheld computers will have a more profound effect on the environmental load.

Dematerialisation of PCs will have a significant and positive effect since the manufacturing process will be less resource demanding. It is estimated that manufacturing of one desktop computer requires 240 kg of fossil fuels, 22 kilograms of chemicals and 1.500 kg of water [Rue 2003]. Compared to other products, computers are very materials intensive. The amount of fossil fuels used to manufacture one desktop computer amounts to nine times the weight of the actual computer versus two times for an automobile. Dematerialising computers from large desktops to tablet PCs will remove substantial amount of material from the product, e.g. hard disk, DVD drives controllers, keyboards, large power supplies, I/O ports, etc. Hence, the manufacture becomes less resource demanding.

Adding another 17 million electronic devices (modems and gateways) to the market every year poses a further challenge to the electronic waste system, since these devices are all physically small and will easily find their way into the household waste stream. This is also the case for smaller PCs such as tablet PCs and handheld PCs.

Increased energy consumption from the increased use of DSL modems and other broadband equipment must be weighted against the lower energy consumption of smaller computers and the phasing out of energy consuming desktop PCs. However, large data centres are also large consumers of electricity and power for cooling and the largest server centres today already pose considerable strain on public utilities, most profoundly found in the largest Google centre in Mountain View California (the California utility companies have at times difficulty in providing enough power to keep the centre running).

It is estimated that these servers and data centres in the US consumed about 61 billion kilowatt-hours (kWh) in 2006 (1.5 percent of total U.S. electricity consumption) for a total electricity cost of about $4.5 billion. This estimated level of electricity consumption is more than the electricity consumed by colour televisions and similar to the amount of electricity consumed by app. 5.8 million average U.S. households. The energy use of the servers and data centres in 2006 is estimated to have more than doubled since 2000. Under current efficiency trends, US energy consumption by servers and data centres could nearly double again by 2011 to more than 100 billion kWh. [EPA2007]

Several key trends toward more efficient microprocessors, servers, storage devices, and site infrastructure systems have been identified that could have a significant impact on the future energy use in data centres. Microprocessor technology is continuously advancing, and trends in server microprocessor technology, such as multiple-core microprocessors, hold great promise for reducing server energy use in the near future. Disk storage devices are expected to become more efficient during the next five years in part because of a shift to smaller form factor disk drives and increasing use of serial advanced technology attachment (SATA) drives. Finally, many data centres are pursuing energy-efficiency improvements to infrastructure systems including improved airflow management and upgrading to water-cooled chillers with variable-speed fans and pumps.

In conclusion, centralisation of computational power allows for improved optimisation of energy use compared to a decentralised structure with billions of individual computers. In large computer centres, decisions can be taken centrally and put into action, environmental regulations can be targeted few stakeholders and investments have better chance of paying off.

Due to the pure scale of the centres, the measures needed to improve the environmental load are thus easier to implement in centralised structures than if they were to be applied in the consumer end.

5.5.3 Regulation

The end of life of computers and monitors will be heavily influenced by the WEEE directive and its future revisions and the use of hazardous substances in the products will be covered by the RoHS directive and its future revisions.

However, some environmental aspects mentioned in the Eco-label criteria, seem not to have been sufficiently covered by the environmental screening in the EuP preparatory study [IVF2007]:

  • Issues regarding flame retardants (poly-brominated biphenyl (PBB) or poly-brominated diphenyl ether (PBDE) flame retardants which might cause harm to unborn children
  • Electromagnetic emissions
  • Mercury content of liquid crystal display (LCD) monitor
  • Design for facilitating recycling (easy to disassemble).
  • Lead and cadmium in plastic parts
  • Mercury, cadmium and lead in batteries

These issues should be address in the regulatory framework.

Finally, to secure optimal energy performance of large servers and data centres, building codes and technical infrastructure regulations should incorporate requirements for energy efficiency and capturing of waste energy.

Most building codes in Member States do not include provisions for data centre heating and cooling use or for the IT equipment itself. If building codes were to incorporate data centre requirements into its commercial energy code, it could have a market transformation effect that would lead to greater efficiency. The US building standard institute ASHRAE currently has four books covering various aspects of data centre design, and a fifth book in preparation that addresses energy efficiency and total cost of ownership. [EPA2007]

Advanced metering would also provide data centre managers with the information they need to save energy and money as part of an effective operations and management practice. Beyond simply measuring electricity consumption, metering also facilitates bill allocation and energy management and helps data centre managers identify energy savings opportunities, verify savings, and participate in utility demand reduction programs.

[1] Further information can be found at: http://energyefficiency.jrc.cec.eu.int/html/standby_initiative_broadband%20communication.htm

 

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Version 1.0 December 2009, © Danish Environmental Protection Agency