The purpose of this paper is to provide information to allow an informal debate among concerned bodies (manufacturers, consumer groups, government), on the impact of possible actions to reduce energy consumption, that could be taken within the telephone sector. Comments on the reference case projections, the savings potential, and further information that could help clarify unresolved issues are invited.

Telephones power supply units (PSUs) form part of the consumer electronics sector, together with TVs, VCRs, IRDs, analogue cable and satellite receivers, home office equipment, HiFi’s and other minor appliances. The Consumer Electronics Sector Review gives the overview of the whole of the consumer electronics sector.

Telephone PSUs covered in this paper are analogue and digital cordless phone base stations, stand-alone answering machines, and mobile phones.

1998 Telephone Power Supply Units Energy Consumption (GWh/year)

In 1998 telephone PSUs consumed around 0.5 TWh of electricity (472 GWh), with mobile telephone supplies consuming the largest percentage (34%) of this figure. In 1998 the total electricity consumption in the consumer electronic sector was about 9.5 TWh, suggesting that telephone PSUs account for something in the region of 5% of the electricity consumption of the consumer electronics sector.

Most of this will be in the standby (‘no load’) mode (i.e. when the power supply is connected to the wall socket but is not performing its primary function). Since these types of appliances are usually left ‘plugged in’ 24 hours a day, the consumption figures presented here are based on standby consumption 8760 hours a year.

The number of telephone PSUs (stock) is set to increase in line with the increase in the number of households and increasing ownership levels. However through proposed voluntary agreements such as the current EU Code of Conduct, and autonomous improvements in technology the effects of increasing stock could be offset. At present energy consumption under the reference case shows a projected increase from 472 GWh in 1998 to 1,034 GWh in 2010. Technically it would be theoretically possible to reduce electricity consumption for telephone power supplies to 179 GWh per annum by 2010, given the assumptions which have been made.

Baseline and projected energy consumption as a result of the use of telephone PSUs are set out in Section 2. The potential for savings is set out in Section 3. The policy programme is currently under development, the current options are set out in Section 4. The CO₂ implications are shown in Section 5. Environmental considerations other than those related to energy consumption are also briefly considered in Section 6. Finally Section 7 highlights the remaining unresolved issues.

2.1 The Overall Picture

Figure 2 Ref: Electricity Consumption by Telephone Power Supplies, UK 1970 - 2020

(Fig 2 Data Set)

Electricity consumption by telephone PSUs in the UK has been rising steadily since their introduction in 1985. The introduction of digital cordless phones could potentially generate a substantial increase in the power demand of the telephone sector.

Although shown separately, it is likely that digital cordless phones (DECT) and mobile (GSM) phones will merge in the near future to become a single product group.

The combined energy consumption for the four categories is projected to be 1034 GWh by 2010 under the reference case assumptions. The reference case assumed that no improvements will be made in the energy efficiency of the technology, apart from the main base of digital cordless phones, which is expected to reduce from 6W to 3W by 2003.

As shown in Figure 2, mobile telephones are at present the most important electricity consumers in this sector, closely followed by analogue cordless telephones. However, by 2010 digital cordless are expected to have overtaken analogue cordless telephones as a result of the expected popularity of digital technology and because of the presence of auxiliary bases in the home in addition to the main base.

Figure 3 Stock UEC of Telephone Power Supplies, UK 1970 - 2020

(Fig Data Set)

Total energy consumption of telephone PSUs is a function of stock and unit energy consumption. Unit energy consumption on telephone PSUs is mainly influenced by changes in technology, which is in turn influenced by changes in policy and functionality. At present the EU is currently negotiating a voluntary agreement (code of conduct) with industry within Europe. As can be seen from the graph above this proposed agreement has not been taken into consideration at this stage.

The stock is mainly influenced by ownership levels and by household figures. The total energy consumption of PSUs in the telephone sector is therefore driven by a number of factors in common with other consumer electronic products.

2.2 Drivers of Change in Energy Consumption

2.2.1 Current Policy

European manufacturers and concerned bodies are currently discussing a voluntary agreement to reduce ‘no load’ energy consumption of all domestic PSUs. If the currently proposed code of conduct is agreed upon, energy consumption of new power supplies could, in Phase 1 (2001), be reduced from 124 GWh/a to 26 GWh/a by 2001. The potential savings from Phase 2 (2003) will depend on the technology adopted by industry.

In addition to the ‘no load’ targets of the code of conduct, there is a commitment to improve the full load transfer efficiency to 60% by 2001 and 80% transfer efficiency by 2003.

At present PSUs do not require an energy label and are unlikely to do so in the foreseeable future.

2.2.2 Technology

There are two main types of power supply technology, linear and switch mode.

Testing of numerous power supplies has shown that there are wide discrepancies in the power supply energy efficiency performance. Further testing will be needed to identify the potential savings of introducing energy efficiency best practice to all manufacturers. Those linear supplies fitted with electronic control circuitry fitted for voltage regulation or output current could potentially improve their performance inline with technological developments in the integrated circuits.

Switch mode power supplies offer greater energy saving potential when compared with linear supplies. Switch mode technology comes at an additional cost at present, however it should be possible to minimise these additional costs as economies of scale take effect.

In addition to the two main options there are numerous options currently being considered by the market transformation team. These options will be addressed in further revisions of this document.

2.2.3 Ownership

Figure 5 Telephone Power Supplies Stock, UK 1970 – 2020

(Fig Data Set)

There has been a steady increase in the stock of telephone PSU’s since they came on the market. The table below represents ownership figures for telephone PSUs in 1998, and the projected ownership in 2010:

Although shown separately, it is likely that digital cordless phones (DECT) and mobile (GSM) phones will merge in the near future to become a single product group.

2.2.4 User Behaviour

The number of hours per day the PSU is used in full load (i.e. charging a mobile phone battery), as well as the number of hours it is left plugged into the wall but with no or reduced load together determine the annual energy consumption.

The consumer can reduce the total energy consumption of PSU’s by disconnecting the unit form the wall socket when it is not performing its primary function. Further research is needed to determine the potential impact of changes in consumer behaviour.

There is limited information available regarding the usage patterns of mobile phone PSU’s, it is assumed PSU’s for answer machines, analogue and digital cordless telephones, are connected to the wall socket permanently.

3.1 Total Savings Potential

The ETP scenario models the way consumption would develop if all consumers purchased the most cost effective energy efficient appliances available on the market and manufacturers optimally improved their products by 2002. Energy efficient appliances may have a higher initial purchasing price, but are cost effective in the long term due to lower running costs. Under this scenario, power demand in standby mode for telephone power supply units is expected to decrease further and more quickly than under the Reference scenario. The ETP line assumes:

• Mobile phone PSU’s standby power demand will reduce to 0.1W by 2002
• Analogue cordless phones’ power demand will reduce to 1W by 2002
• Digital cordless phones’ power demand for the main base will reduce to 1W and the auxiliary base will reduce to 0.1 by 2002
• Answering machines’ power demand will reduce to 0.1W by 2002

The table below highlights the savings that would be achieved under the ETP scenario for each appliance:

The persistent increase in the electricity consumption of power supply units for digital cordless telephones under the ETP scenario is due to the fact that the power demand of the main base has been assumed to remain constant under the ETP scenario because of increases in functionality. This may be unduly pessimistic.

Figure 6 Electricity Consumption by Telephone PSU’s, Ref and ETP, UK 1970 - 2020

(Figure Data Set)

The energy saving potential by UK telephone PSU’s use is summarised in figure 6. It is shown that technological change can achieve a reduction of 855GWh per annum compared with the reference projection by 2010.

The scope for reducing unit energy consumption lies in more energy efficient PSUs. The means of achieving are based on technological improvements and policies, which stimulate these developments

3.1.1 Technological Improvements

Improvements in efficiency are likely to come from manufacturers producing switch mode supplies rather than the linear power supplies. The specific impact of such a development will need further investigation before estimates can be presented.

3.1.2 Behavioural Potential

No load consumption (in PSUs) account for a considerable amount of the total electricity consumed by telephone power supplies in 1998. Persuading households to remove power supplies from the wall socket when there is no load, could therefore access some of these potential savings.

3.1.3 Infrastructure Changes

At present there are no apparent infrastructural changes that are likely to take place in the near future.

Market transformation policy options for telephone PSUs are currently under development. Various options will be considered, such as:

• Voluntary agreements
• Minimum standards
• Energy Labels
• Procurement programmes

Comments on the potential impact or benefits on the above options are invited.

Figure 8 CO₂ Emissions from Telephone PSU’s Under Ref, and ETP

(Figure Data Set)

CO2 emissions are expected to rise from 0.06 MtC in 1998 to 0.13 MtC in 2010. If the ETP technology achieved 100% market penetration by 2005, carbon production could be reduced to 0.02 MtC by 2010. However in order to access savings a strategic and integrated policy programme has to be developed and implemented.

The drivers behind CO2 emissions are a combination of changes in electricity consumption in the use of power supplies and changes in fuel mix. CO2 emissions per kWh of electricity produced have been on a downward trend since 1970 but are expected to start rising from early in the new millennium.

• Energy and waste in the production phase
• Disposal / recycling at end of use cycle

These are important issues to consider for a sustainable product use and more information on this matter will be gathered in the course of this consultation process. More discussion is needed on the potential effects of these points.

In addition to any comments you may have on this paper, there are a number of issues for which we would like specific comments. These issues are listed below. In either case, please send your comments to the Market Transformation Programmes Consumer Electronics Sector Manager.

Questions

• How many mobile phone power supplies are actually left connected to the wall socket with no load?
• Is the projected power demand of the ETP technology feasible?
• If the propose EU code of conduct is adopted what would be the likely impact on the manufacturer and the customer?
• Are there any new technological options available to achieve the ETP targets?
• How will future developments in functionality affect power demand?

• What policy options do you believe to be most appropriate for this sector?
• The reference case assumed that no improvements will be made in the energy efficiency of the technology, if improvements do take place what would be the likely effect?