Tumble dryer energy habits

Tumble dryers are a popular fixture of many households in the UK, with 42% owning one. This figure is up from 35% in 2000 and is expected to rise still further to 45% by 2020. There are plenty of different models on the market with differences in technology. Some homeowners choose integrated tumble dryers as part of a fitted kitchen, others decide between air-vent dryers and condenser dryers, and the advent of gas tumble dryers provides an additional choice. Sales of the various makes and models have been increasing more quickly in the past few years – it may be that their lifespan is dropping - so the figures may be underestimated. As of 2007, the standard energy consumption of each tumble dryer in the UK was about 354 kilowatt/hours per year. They’re used on average 148 times throughout the year, which is 60% of the number of times an equivalent washing machine is used when households own both. The energy consumption for a dryer is 2.5 kilowatt/hours per use and it is thought that this may drop slightly as tumble dryers become more energy efficient. Experts believe that the average energy efficiency of tumble dryers will increase by half a percent every year. Overall, domestic tumble dryers are responsible for the consumption of 4.25 terawatt/hours of electricity in the UK every year and this figure will increase to around 4.53 terawatt/hours unless energy efficiency improves across the market. In an era when rising fuel prices mean that householders are searching for cheaper bills, tumble dryers are a main electricity user in the home.

Tumble dryer energy rates explained

Tumble dryers adopted a European Energy Label standard in October 1996. This labelling system introduced an A to G energy efficiency classification for all models of tumble dryers sold on the market. The classification exists for both vented and condenser dryers as well as stand-alone and integrated tumble dryers. Most appliances for sale on today’s market are C-rated in terms of being energy efficient, but many older, more inefficient models are in existence in UK homes. This is because tumble dryers have a relatively long lifespan of 13 years. It’s worth noting the different energy consumption between ratings to get an idea of the potential savings. For vented tumble dryers with six kilogram loads of washing, F-rated appliances use 5.5 kilowatt/hours of electricity; C-rated appliances use 4 kilowatt/hours and A-rated tumble dryers use 3.1 kilowatt/hours. By these figures we can see that A-rated dryers save nearly half of the electricity consumed per use by F-rated appliances. In comparison, F-rated condenser dryers with the same load use 6 kilowatt/hours of electricity, C-rated appliances use 4.4 kilowatt/hours and A-rated condenser dryers use just 3.3 kilowatt/hours, so it’s pretty much the same story. The UK government’s Market Transformation Programme hopes that, by 2010, all tumble dryer purchases will be for A-rated appliances utilising heat pump technology at 1.9 kilowatt/hours per use, although this is an ideal situation and market uptake of the new technology may not happen as quickly as it’s hoped. Another A-rated tumble dryer currently exists on the market, but achieves its energy efficient rating thanks to a lengthy eight hour drying cycle.

Reliability of ratings

The test standard on which the Energy Label ratings for tumble dryers are based is well regarded, as the tests are properly established, robust and reproducible. This does not eliminate potential problems in regards to the reliability of ratings, however. Householders need to be made aware of potential problems surrounding the test methodology of these ratings to understand better the situation across the market as a whole. In the test, the weight of a washing load used within the appliance is checked through what is called the ‘bone-dry’ method. This method does not produce consistent results and can possibly lead to variable tests in associated product tests. Although this is a small part of the testing process for tumble dryers, it has the potential to become a major issue and further examination needs to be made to discover whether the ‘bone-dry’ method is really the correct one to be using. In addition, the test only covers the two types of tumble dryer powered by electricity: vented dryers and condenser dryers. Gas tumble dryers are an alternative product, long available on the market, and have become more popular in recent years. Ideally, the test should be extended to cover the energy efficiency of gas tumble dryers as well as electric ones, and then the two types of dryer could be compared side-by-side in terms of energy efficiency and carbon emissions. Without the existence of proper testing, gas tumble dryers cannot be promoted as energy efficient or good for the environment.

Energy Label problems

As well as issues regarding the reliability of the ratings used in the European Energy Label scheme, other potential problems are worth noting. For instance, some people think that the label ratings are slightly biased towards condenser dryers as the test methodology favours condenser technology over air vent technology. Creators of the Energy Label will never admit that condenser dryers are favoured more highly due to the test process, but it’s worth keeping in mind when comparing the two types of dryer. In regards to the ‘bone-dry’ wash loads that are used during the test process, simply changing the test by increasing the moisture content of the wash load wouldn’t work. This is because doing so would automatically raise the ratings of all tumble dryers on the market by a single grade, so C-rated appliances would become B-rated, and so on. This is an unwanted scenario as, essentially, the energy efficiency of tumble dryers would suddenly improve across the board without any action on the part of manufacturers. Finally, the duration of drying cycles for tumble dryers is not currently displayed on the energy label. Typically, the energy efficiency of an appliance is worked out on the most economic cycle, which uses less electricity and therefore takes longer to run. In real-life usage, many householders may not have the time to run the longest cycles and they may never be achieving the energy efficiency that the energy rating promises. Worse still, there’s no way they can realise that they’re not unless they can take the duration into consideration at the time of purchase.

Tumble dryer standby power consumption

One area of energy consumption that exists for many domestic appliances and home products across the UK as a whole is that of standby power consumption. Understandably, manufacturers are not keen on highlighting the potential drain on resources that may occur when their products are left in standby mode, so the onus is on householders to become more aware of the various ways in which their products can draw power. In the credit crunch era, the only way to achieve cheaper bills is to be as energy efficient in the home as possible. Research undertaken by the UK’s Market Transformation Programme has revealed that some tumble dryers consumed power when the ‘on’ button was engaged and the machine wasn’t in operation. Similarly, a smaller proportion of tumble dryers also drew energy when left in the ‘delay timer’ mode. In the survey conducted by MTP, 36 appliances were tested. 38% of the tumble dryers drew an average 2.6 watts of standby consumption when they were switched on, while 5% drew on average 2.9 watts when the delay timer was being operated (e.g. when the dryer had been programmed to work overnight). With warnings of financial gloom everywhere we look, we need to do everything we can to reduce fuel bills and make ourselves more energy efficient. Remembering that tumble dryers may draw power when left in the standby mode and turning them off whenever they’re not being used can help us save power and avoid letting the credit crunch have too much impact on our lives.

Electric tumble dryers

Electric tumble dryers are the appliance of choice for the UK market. With this type of product making up 95% of dryers sold in the country, alternative technology appliances such as heat pump and gas tumble dryers barely get a look in. The energy efficiency of electric dryers has been steadily increasing in the last decade but has now come to a virtual standstill. This is because the design of these tumble dryers has become as energy efficient as is possible and without major revamps in dryer technology, it can go no further. There are two main categories of electric dryer. The first is the air vented dryer, which vents the warm air from inside the appliance outdoors through a vent pipe. 60% of sales of electric tumble dryers are of the air vented type. This type of dryer is slightly more energy efficient than condenser dryers as it has to do less work as the warm air is expelled rather than cooled down for condensation. Condenser dryers heat air inside the appliance electrically before the warm air is processed through an air condenser to produce moisture. Unlike vented dryers, the moisture is collected into a receptacle which is emptied by the householder at various intervals. The good thing about condenser dryers is that they don’t need an external vent as everything happens inside the appliance. There’s no need to plumb a hole through a wall or hang a vent pipe from a nearby window. This aspect makes them popular as integrated tumble dryers, as the dryer can effectively be ‘hidden’ from view within a fitted kitchen.

Gas tumble dryers

If you’re looking for cheaper bills then purchasing one of the new gas tumble dryers available on the market may be an option. Unfortunately, gas tumble dryers are nowhere near as popular as their electric counterparts and the reason for this is that they’re more expensive to buy than an electric dryer. In the late 1990s, only 0.3% of UK households owned a gas dryer and things haven’t changed much in recent years; by 2010, that figure is only expected to increase to 0.4%. Barriers to increasing ownership include the necessity to attach these dryers to a gas connection point, which for most householders means installation costs on top of the purchase price.UK Gas tumble dryers possess the same type of technology as that found in vented and condenser dryers. The only difference is that the appliance is powered by a gas burner rather than an electric heating element. The reason gas dryers are so good for the environment is that gas is a primary fuel whereas electricity is a secondary fuel and this means that gas only produces half of the carbon dioxide emissions of electricity. If these products are adopted as part of the 2009 Carbon Emissions Reduction Target scheme, sales of the gas tumble dryers may become subsidised which means they’ll be cheaper to buy. Although they’re not currently part of the European Energy Label scheme, there’s no real reason for them not to be. And the sooner householders realise that the reduced running costs of gas tumble dryers do make them a viable alternative, the more we’ll be able to fight the credit crunch.

Heat pump tumble dryers

The heat pump tumble dryer utilises a new type of technology and along with gas tumble dryers, this type of product makes for an energy efficient purchase when compared to standard electric tumble dryers. In fact, heat pump dryers are 30% more energy efficient than standard electrically heated dryers, so that’s close to a third of a saving on energy consumption. The technology of heat pump dryers is similar in set up to that of condenser dryers, but varies in that the hot and cold plates of a heat pump control the heating and condensing part of the system. Unfortunately, the heat pump part of the system is expensive to produce which is why heat pump dryers aren’t as popular as conventional electric tumble dryers. This is a shame, as with 30% increase energy efficiency they’re fantastic for the environment. It’s no surprise that heat pump dryers are one of only two A-rated appliances currently being sold on the market. So far, heat pump dryers have been too expensive to find general acceptance in the UK market. However, recent price reductions on this type of product means that these tumble dryers are becoming a viable alternative to conventional purchases. In the time of a credit crunch, householders are having to do all they can to reduce fuel bills and make savings on power consumption. With reduced running costs, heat pump dryers may well become far more popular than their current status would suggest.

Future measures

The economic climate is currently in turmoil. Cheaper bills seem to be a thing of the past and the credit crunch is affecting our lives in many ways. The running costs of home appliances can be a drain on our resources when the rise of fuel prices is taken into account, and tumble dryers are a big home user of electricity. However, there are some positive steps being taken to improve the power consumption of householders and perhaps even help them to reduce fuel bills. UK fiscal incentives are currently in operation to reduce the price premium for the most energy efficient tumble dryers on the market – this covers A-rated dryers, and both stand-alone appliances and integrated tumble dryers. At the other end of the scale, an industry standard is in place to remove the least energy efficient models from the market by 2011. Meanwhile, the UK’s Energy Efficiency Commitment (EEC) is planning to encourage sales of both heat pump and gas tumble dryers in 2009 as both types of product are more efficient than existing electric tumble dryers. Unfortunately, the conventional technology used by electric tumble dryers is unlikely to improve much in the future. Manufacturers have maximised the efficiency of their products to the stage where they can go no further, and consumers are now having to look to the new technology of heat pump and gas tumble dryers in order to increase their energy efficiency and reduce fuel bills in the process.

Energy saving tips

One of the ways to combat the credit crunch and achieve cheaper bills is to use energy saving measures where possible with your home appliances. Tumble dryers are no exception and it doesn’t matter if you own one of the stand-alone dryers or integrated tumble dryers on the market – there are ways you can decrease your power consumption and become more energy efficient as a result. Making use of your dryer’s delay timer function, if you’re lucky enough to have one, is one of the most straightforward ways to save cash. By setting tumble dryers to run overnight, you may be able to take advantage of reduced electricity tariffs and it’s worth checking figures with your energy supplier to see whether this option is worthwhile. Elsewhere, always try to dry the same types of fabric together. Drying different fabrics together can mean that they dry at different speeds and some might have to go back into the dryer for a second spin. Drying only the same type of fabric will ensure that the drying process is both even and fast. Limiting the usage of tumble dryers is probably the easiest way to cut down on energy consumption. Use the high spin cycle on a washing machine to extract as much moisture from your load as you can before popping it into the dryer – washing machines use less electricity so you’ll be cutting down on costs. Also, always fill your tumble dryer to maximum capacity where you can.