It’s in the Stars: The importance of efficiency ratings
With household appliances the main contributors to a home’s energy use, it makes sense to ‘buy smart’ and ‘use smart’. Eva Matthews investigates how to achieve savings and help save the planet.
This article was first published in Renew 134 (January-March 2016).
When buying anything for the home, the item’s upfront cost, look and functionality are prime considerations. For some of these—furniture, for example—this is where the buck stops. But when it comes to ‘big ticket’ household items such as whitegoods, computers and home entertainment systems, heating/cooling units and hot water services, another element comes into the mix: ongoing running costs. Whether powered by electricity or gas, these costs accumulate over the life cycle of an appliance or system, and so the energy efficiency of these items becomes an important consideration in the purchasing decision. It’s not just about the money, of course—greater energy use means greater greenhouse gas emissions.
Energy efficiency is determined not only by the inherent mechanics and technology of an item, but also by its location (in Australia, as well as within or around the home), its age, the use of its various features and its level of maintenance. Achieving the best energy efficiency, then, becomes a combination of buying the item that uses the least amount of energy to achieve the functionality you require, as well as operating it in a way that maintains optimal efficiency over its life cycle.
A 2008 Australian government study on residential energy trends forecast ongoing growth of around 5% per annum in appliance energy use. However, the latest study suggests consumption will be fairly flat: our appliance efficiency programs and other factors are working. But to maintain and improve on this trend we need to keep working to improve efficiency to offset population and economic growth.
Buying efficient appliances
So how do you buy energy-efficient appliances and then use them most efficiently?
Regulatory measures have been put in place to encourage manufacturers to improve the efficiency of the products they send to market, and to help consumers make the best choice to meet their needs. These are the Minimum Energy Performance Standards (MEPS)—which specify the minimum level of energy performance required of appliances, lighting and electrical equipment before they can be offered for sale or used commercially—and Energy Rating Labelling, which uses the ‘Star’ energy rating system to help consumers compare like products in terms of their energy efficiency.
Australia was among the first in the world to introduce mandatory energy rating labelling, pre-dated only by Canada (1978) and the USA (1980). It was introduced in Victoria and New South Wales in 1986, and a national scheme agreed to in 1992. However, it was only 15 years ago, in 2000, that it was fully legislated in each state and territory.
We are all familiar with Energy Rating Labels (ERLs)—the red ‘rainbow’ filled with stars, atop a yellow box, stuck to the front of a dishwasher, fridge or other major appliance. Indeed, a review of their effectiveness, completed in March 2014, reported that 97% of surveyed consumers recognise the ERL. Further, it noted that 62% use the ERL to research an appliance’s energy use, and 80% use the information on the ERL to compare appliances when making their purchasing decision.
The key pieces of information on an ERL are the number of Stars (up to 10)—the more Stars, the more energy efficient the appliance—and the energy use of the appliance in kilowatt-hours (kWh) per year when tested to the relevant standard. The Stars give you a quick visual cue as to an appliance’s energy efficiency, while the kWh rating gives more detail as to its actual average energy use. It’s important to consider the energy use figures, rather than just the Stars alone, as the Star rating is a measure of ‘efficiency’ for a given sized appliance. Thus, a larger appliance may be given the same Star rating as a smaller version, but use more energy.
The website www.energyrating.gov.au and its associated mobile app can be used to calculate the running cost of various models of appliances across the categories included in the ERL program (air conditioners, clothes washers and dryers, fridges and freezers, dishwashers, computer monitors and televisions). You can select the models you’re considering purchasing, key in your electricity cost and choose the likely life cycle of the appliance, and the yearly running costs are calculated for you, allowing you to make an easy comparison between the models (noting that actual cost will vary per household, depending on how and where you use the appliance).
The Energy Ratings website also includes a list of all models of a particular appliance type with their Star ratings, which can be useful as a starting point to find the best options available; access it by the button ‘Registration database’ on the website’s home page.
There are numerous other sites hosted by energy retailers and suppliers, and state governments, that have online running cost calculators for appliances in the ERL program, as well as lighting, heaters, hot water services, pool pumps and small appliances. For example, see www.smarterchoicecalculator. com.au and www.switchon.vic.gov.au. These all vary slightly in terms of the data they’re based on, the search/input options they provide and what information they require from you, so it’s worth checking them out. The good thing about these is that they allow you to key in your specific frequency of use, which can give a more realistic running cost for your household. If you’re a subscriber to Choice, or have access to a library that subscribes, you can also get standard life cycle running costs for various models of the appliances they’ve tested, alongside the features and specifications, to help you with your purchasing research.
Another useful calculator is the EPA greenhouse calculator, which allows you to compare behaviour and installation factors as well as equipment energy efficiency. It only reports greenhouse gas emissions, not running costs, but you can convert as described in the Assumptions link on the home page.
It seems sometimes that the more energy efficient an appliance is the more it costs up front and this may, at first glance, dissuade you from buying it. However, when you take into account the life cycle running costs, you may find that (with the money you’d save over the long term) it’s worth paying a little more up front for the more efficient model. And, even for appliances at similar, middle-range purchase prices, there can be big differences in energy running costs, so it pays to do your homework. For example, see Figures 1, 2 and 3 for the performance ranges for dishwashers, fridges and air conditioners. As you can see, selection of size also matters!
Operating appliances efficiently
While ERL information and running cost calculators can help you ‘buy smart’, you can also optimise the efficiency of the appliances you own by the way you operate them.
There are a number of factors that affect how efficiently an appliance will run. Some are common to all, and some specific to particular types. Common ones include its age, how well and often it’s serviced, what time it’s used, which features are utilised and how much air is able to flow around it. For air conditioners, location within/around the house and whether it’s in the tropics or in colder regions make a difference. Air conditioners or heaters will be affected by a home’s design, draughtproofing and insulation. Some of these factors may be beyond your control–for instance, you may be renting and therefore can’t do anything about the home’s insulation–but there is still a lot you can control to make sure your appliances operate most efficiently (Tips are listed at the end of the article.) The same websites that have the ‘running cost calculators’ also include further handy hints for using appliances wisely, as do www.yourhome.gov.au, www.yourenergysavings.gov.au and www.sustainability.vic.gov.au.
A word on standby power
Leaving appliances on when they’re not being used can account for up to 10% of household electricity usage. This is not insubstantial! A microwave oven, for example, can use more energy in standby mode—powering the clock display—than it does to cook/heat food over the course of a year. So, ‘running appliances efficiently’ is also about considering when they can/should be turned off. As noted in the latest Residential Energy Baseline Study: Australia, August 2015, standby power has been dropping for new appliances, but it can still be significant.
Replacing old appliances
Even assuming you do everything you can to operate your appliances efficiently, in some cases the best thing you can do—for your hip pocket and the environment—is to replace old with new. In general, the older the appliance, the less efficient it will be and the more it will cost to run. Even though you’ll need to outlay substantial cash to buy a new unit, the savings you’ll make from cheaper running costs will go a long way to offsetting the changeover cost.
For example, if you have a 15-year-old fridge, it probably has five years before it will need to be replaced. Conservatively, it is likely to cost you $100/year more to run this fridge than a new, efficient model. So, you could put the $500 you’d save over that time towards a new fridge now, and also enjoy the extra features it will offer over the old one.
And when you are ready to get rid of an old appliance, dispose of it thoughtfully— talk to your local council about recycling programs in your area. Planet Ark’s website www.recyclingnearyou.com.au also has a useful search function that provides a list and contact details of recyclers in your area (including council waste transfer stations, scrap metal businesses and charities).
Monitoring actual energy use
While the data from appliance labels are a good starting point for choosing efficient appliances and systems, knowing when, where and how much energy is actually being used is key to reducing energy consumption and saving money.
Technologies for monitoring household energy use, in real time, include:
- electricity ‘smart meters’ that transmit near-real-time consumption data (these have been installed, as a result of government initiatives, across most of Victoria and also in parts of WA and SA)
- web portals and in-home displays that display your energy-use data, as measured by your smart meter and transmitted to/recorded by your electricity supplier (typically at half-hourly or hourly intervals); non-smart meter versions are also available
- plug-in power meters, such as the Power- Mate, for individual appliances.
Web portals enable you to view the flow of electricity use throughout the day and also compare it with other days/time periods. Linking this with your knowledge of what appliances were used in peak times allows you to consider how/when they might be used more efficiently.
In-home displays provide a greater level of detail, and can be viewed in near-real-time. For example, switching an appliance on and off, you can see how much energy it is using and how much that is costing you; doing this at different times of the day/night can alert you to potential cost savings.
Power meters, connected between the mains socket and the appliance, tell you how much energy is being used—you can see instantaneous power draw and energy use for a period of time. It is wise to look at energy use over a full day or more (and for some appliances, such as fridges, in different operating temperatures), as many appliances use different amounts of power depending on their operation cycle (e.g. fridges draw more power to cool after the door is opened or when defrosting).
See ‘Meter Matters’ in Renew 130 for more info on energy meters.