BNW22 Energy Saving Recommended Tumble Dryer Endorsement Review 2005
For Consultation Purposes
The following note has been produced by Defra’s Market Transformation Programme and the Energy Saving Trust to consider the current and possible future criteria of energy saving recommended endorsement.
The aims of the note are to present current information on tumble dryers and explore options for revised energy saving recommended criteria. It should be considered as providing points for discussion by stakeholders, the Energy Saving Trust and the Market Transformation Programme.
The options for future criteria include various technological features, energy label claims, and make reference to the current tumble dryer market.
1. Energy Saving Recommended – Need for Review
The current standard for the endorsement of tumble dryers under the energy saving endorsement scheme was established in 2000. It is a requirement of the Scheme to annually review the position of the endorsement criteria with respect to the Scheme objectives and market and technological developments. In the case of tumble dryers, this element of the Scheme has not been fully adhered to. The Scheme has an objective, on occasions where products can be differentiated by their energy efficiency (and sustainability) properties, to endorse a maximum of approximately 20% of the market. In light of the above, the need for a review is clear.
Current criteria
The current criterion for energy saving recommended endorsement is EU Energy Label A or B rating for energy efficiency on full size air vented and condenser tumble dryers.
Other examples highlighting best practise
Tumble dryers are not covered by European award schemes such as the EU Ecolabel, the Nordic Swan or the Blue Angel schemes.
AEG won the International Energy Agency Demand Side Management Award for Excellence in 1999 with a heat pump tumble dryer. This tumble dryer achieved the energy efficiency required for EU Energy Label A rating, but despite an initial launch and subsequent relaunch in mid 2005 it has yet to become a successfully marketed product in the UK.
2. Current Market Picture
Market information (Gfk) for 2004 shows sales penetration of endorsed tumble dryers at less than 1%.
There was only one model of A rated tumble dryer and no B rated models recorded by Gfk as available in 2004. Of all models sold, 80% were C rated, 10% D rated and the remainder where the label was known were F or G.
The A rated tumble dryer, the White Knight CL847, achieves its rating by using an extended low temperature programme that takes over 9 hours to dry a full 5kg load. It also has an option button to set a normal length high temperature programme.
The AEG heat pump model was relaunched in 2005, and claims to dry a 6kg in a normal programme time, claiming “the World's only tumble dryer with an 'A' rating for a standard cycle time”. Typical AEG tumble dryers take approximately 2 hours to dry a full load, so it is assumed that the heat pump dryer also takes approximately 2 hours to dry a full load. The programme is also a low temperature one, but the high level of efficiency is achieved through the heat pump system. It is a condenser system, so does not need external venting.
The market has not moved towards ratings better than C as these cannot be achieved with current technology of vented and condenser dryers, except by the method shown above of running an extended programme at a low temperature. Some manufacturers have suggested that B rated models might form part of their ranges in the near future, but these have yet to be launched and the way they achieve these ratings is not known.
Tumble dryer market (household) penetration is around 40%. Sales in 2004 were 1.22M units.
Condenser and ventilated models are the two main types of electric tumble dryer on the market. In 2004 condenser models accounted for 40% of sales, and ventilated the remaining 60% of sales (Gfk). The proportion of condenser to ventilated models is rising, although there is no consensus as to the rate of change.
Tumble dryers are also available in full-size and compact models. In 2004 sales were split as follows:
|
Size
|
% sales
|
|
Compact (3.5 kg or less)
|
18%
|
|
Full size 4 to 5 kg
|
19%
|
|
Full size 6 kg
|
60%
|
|
Full size and ‘oversize’ over 6 kg
|
4%
|
Further background information on the tumble dryer market can be found at the end of this note.
3. Options for revision of energy saving recommended criteria
The following options provide areas for discussion and the analysis is based on limited market information. Following initial consultation and discussion on the options below it is recommended that a fuller market review is undertaken to consider any criteria changes in terms of current market penetration and future trends.
The market information used below includes top line information on sales from GfK for 2004, a review of models available in Comet and John Lewis in July 2005, and information from the models included in the Market Transformation Programme compliance testing in March 2005.
i) Sensor drying models rated C or better
Rationale:
As has been the case with energy saving recommended endorsement of dishwashers, a logical option is to consider other aspects of the product that impact on resource use.
The option is therefore to require tumble dryers of EU energy label rating C or above that use a sensor to stop the machine at the required level of dryness.
The benefit of machines with sensors is two-fold. First, for any load, they will stop when the load is dry, which will prevent over-drying if users do not accurately set a timer. Also, machines with sensors usually have a range of levels of dryness that can be selected. This again can prevent over-drying of items, which are to be ironed by selecting the iron-dry or damp cycle. Some sensor models also display the level of dryness that has been reached as the programme progresses which allows users to remove items when they reach a particular level of dryness before the whole load is dry.
While the extent of over-drying with tumble dryers with timers is not known, taking away the need to check loads while they are drying is more convenient for users. The Which? laundry survey in 2001 showed that 56% of owners with a sensor dryer no longer checked loads in mid-cycle, and of the owners with a sensor dryer, 72% were satisfied with how it works (only 13% said they were not and the rest were don’t now or don’t use the facility). Owners of sensors dryers are therefore generally satisfied with their tumble dryer and find it more convenient to use than a standard timer model.
Potential:
Of all sales in 2004 18% were sensor dryers. 14% were condenser models, from 14 brands with some tradebrands and exclusive models, and 4% were vented models from 10 brands with some tradebrands and exclusive models.
The calculation used to assign the EU energy label class gives an ‘allowance’ to condenser models of approximately 0.05 kWh per kg for a C rated model. So under test conditions, the typical C rated condenser model that takes a 6kg load will consume 0.4 kWh per load more than the similar vented model. However, if a tumble dryer is installed in a location which is not similar to the test conditions, an unheated garage or utility room for example, the energy consumption of a vented dryer may increase significantly compared to the condenser dryer because it uses energy to heat the cold air it draws from the room. The difference in consumption under test conditions should not be therefore used to discriminate between condenser and vented tumble dryers unless there is evidence for in-use consumption that demonstrates one type is significantly better than the other.
Sensor models are available from a range of manufacturers. They tend to be more expensive than the basic standard timer models, although models are available from around £200.
Conclusion:
Sensor dryers are available from a number of manufacturers and account for almost 20% of the market, and the majority of these are condenser models. The level of coverage is therefore what is required by energy saving recommended criteria.
There is no reason to discriminate between condenser and vented models on the basis of declared energy consumption because there is no in-use evidence that one performs better than the other in typical household use.
ii) Low temperature option
Rationale:
As discussed above, the current method employed by the A rated tumble dryer to achieve its low energy rating is to use a reduced temperature system over a long period. It is possible that the low temperature options found on standard machines could be employed in the same way to decrease the overall energy used for some loads.
Potential:
All tumble dryers have at least two temperature settings, a high or normal for cotton fabrics and a low temperature option for synthetics and other fabrics that might be damaged by higher temperatures. Some models, particularly the larger capacity American or semi-industrial style declare a number of other temperature settings.
Conclusion:
There is no evidence that on standard machines the low temperature option offers any energy saving potential for typical cotton loads. In addition, longer cycle times are unlikely to appeal to consumers, and as this is an option, users are likely to use the full power setting whenever possible.
iii) Minimum capacity
Rationale:
To achieve greater levels of efficiency only tumble drying larger loads is usually seen as desirable.
Potential:
The market for tumble dryers is already focussed on 6 kg loads, with 60% of sales in 2004 being 6 kg models, although some larger capacity models within the standard footprint have begun to be sold. It is not known whether owners actually fill their tumble dryers to capacity, but generally thought that users usually only half fill their machines. Indeed for loads over 6 kg it is unlikely that they have a washing machine capable of producing more than 6 kg of washing unless they have a matching one from the same manufacturer. In 2004 96% of sales of washing machines were of capacities of 6 kg or less.
Conclusion:
Setting a requirement for a maximum load over 6 kg would not necessarily promote models that deliver higher levels of efficiency when used in typical situations by consumers.
Setting a load requirement of 6 kg would capture the majority of sales, and within this a good proportion of the sensor models, with some 13% of all sales in 2004 being 6 kg machines with sensor controls. However, the majority of these (12%) were condenser models.
iv) Moving to EU Energy Label C
Rationale:
EU Energy Label rating class C offers the best level of efficiency with traditional technology on the market.
Potential:
Sales in 2004 were 80% EU Energy Label class C rated. Setting a criterion of only C rated would exclude some full size machines and all compact machines from the scheme.
Conclusion:
Setting a criterion of only C rated would give much more than 20% of products that are required by the endorsement scheme.
v) Endorsing Gas tumble dryers
Rationale:
Using gas as an energy source in the home is considered advantageous because it produces less carbon. It also costs the user less to run.
Potential:
A comparison supplied by a manufacturer of gas tumble dryers suggests that a C rated electric tumble dryer would produce 0.088 kg of carbon per kg of load, compared with a gas tumble dryer that would produce 0.039 kg of carbon per kg of load. Gas tumble dryers still require a small amount of electricity to power the electronic systems. The running costs are also significantly lower, and have been estimated at less than a third of electric dryers.
There is only one manufacturer supplying standard gas tumble dryers to the UK domestic market. Other major manufacturers have semi-industrial or large capacity models suitable for use in workplaces such as nursing homes or hairdressers that are available on the UK market. And other brands of domestic gas tumble dryer are available in other European countries.
There is an additional cost associated with gas tumble dryers in that they require installation by a Corgi registered gas engineer. Unless a dedicated gas supply is already in place this may require additional gas piping to be installed and could be seen as inconvenient by some consumers. They should also receive regular service checks, which add to the ongoing costs. Gas dryers also need ventilation to the outside, which may make them unsuitable for some places where only electric condenser dryers could be used.
Less than 0.5% of the stock of tumble dryers in UK households are estimated to be gas tumble dryers.
Conclusion:
Including gas tumble dryers in an endorsement scheme may encourage other manufacturers to enter the UK market. However, the financial costs of installing and running a gas tumble dryer should be calculated to demonstrate the cost of this technology. It may be that long term cost savings are only really achieved at higher levels of use because these costs outweigh the cheaper energy costs. It may be that subsidies such as the Energy Efficiency Commitment are required to promote the energy and carbon savings over the running costs of gas tumble dryers.
Also, to ensure longer term promotion of gas dryers, action could be taken to engage builders and encourage them to install an appropriate gas point in new build developments.
4 Future options
The scheme should be prepared to be flexible with the criteria to accommodate new technology and models.
The limited number of A rated and gas appliances currently on the market in the UK restrict consumer choice if the scheme only accepts these technologies. However, they could be included within the scheme if a category of ‘most efficient’ is adopted that sits above any other criteria that are adopted such as the C rated sensor models suggested above.
So that users can compare the two classes of recommended products typical annual running costs and scenarios should be calculated that demonstrate the costs over five years that include, in the case of gas, the installation and service costs, as well as the energy cost.
5 User information
As well as encouraging users to use their tumble dryers in the most efficient way, the scheme could also require manufacturers to include a range of consumption data in the handbook. A review of handbooks supplied with the models tested by the Market Transformation Programme in early 2005 showed that only 6 of the 20 had any energy consumption information over and above the data on the EU Energy Label, and these 6 came from 2 companies.
It could be suggested that the energy consumption for a range of typical scenarios is included in the handbook. Best practice currently is to give electricity and time for drying the maximum load that has been spun at a range of spin speeds. This demonstrates that both energy and time can be saved when drying loads that have been spun most efficiently. If the model is a sensor model, this also includes data from the different programme settings such as hand iron, as well as the normal and intensive.
Manufacturers could also be encouraged to give data that represents more typical use such as loading with half maximum loads.
Background information on tumble dryer market trends
Ownership is highest among family groups, with approximately 50% of households with children having a dryer, opposed to the overall average of around 40%.
Condenser dryers have increased in popularity because they can be situated anywhere there is a convenient socket, and do not need venting to the outside of the building.
Use is generally seasonal with people using tumble dryers more frequently during periods of wet weather. A Which? reader survey in 2001 found that in dry weather respondents dried 2.4 loads in a dry week and 4.3 loads in a wet week. Current Market Transformation Programme modelling assumes an average use of 148 times per year, and an annual energy use of 373 kWh.
There is likely to be steady replacement and new acquisition of tumble dryers, unless a viable lower energy solution is marketed.
Recent innovations seen on some tumble dryer models that may impact on energy consumption:
· Drying rack for shoes/jumpers/delicates – (may encourage greater use of tumble dryers)
· Fabric smoothing and woollen freshening cycles for dry items - (may encourage greater use of tumble dryers)
· Energy save option – the element only turns on if the ambient air is not warm enough to dry fabrics
Compact models are less energy efficient per kg of load than full size models and are rated E or F on the EU Energy Label.
People are sometimes faced with choosing between a washer dryer and a washing machine and separate tumble dryer. In theory there is little difference in terms of energy consumption using a full load between combined and separate products, i.e. the theoretical difference between washing and drying a 6 kg load using a B rated washer dryer (best currently available in UK at 4.86 kWh or less) and an A rated washing machine and C rated vented dryer (combined total is 1.14 + 4.00 = 5.14) is 0.28 kWh. However, with a washer dryer there will be additional water used in the drying cycle as all washer dryers use water to cool a surface to condense the heated air from the wet load, this can add between 20 and 130 or more litres for drying a full load. In practice there will be a difference in both wash and drying energy efficiency when the machines are filled with part loads and set to different temperature wash programmes other than the standard 60°C cotton programme declared on the energy label.
Users of tumble dryers should be encouraged to use their appliances as efficiently as possible, i.e. planning washing to take advantage of periods of better weather so they can dry outdoors, running the tumble dryer with a full load, using a washing machine with a good spin extraction efficiency rating and using the higher spin speeds when possible, if a sensor option is available using the iron dry or damp setting if ironing is required.
This Consultation Briefing Note was prepared by Nicola King, Market Transformation Programme, in collaboration with Tom Lock, Energy Efficiency Accreditation Manager, Energy Saving Trust, for a review meeting in October 2005.