Where does it go? Is that what you wonder when you open the power bill? We’ve estimated typical running costs for a range of heating, kitchen, lighting and general household appliances so you can work out how to make the most effective savings in your home.
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You probably aren’t going to replace your fridge-freezer just because it’ll cost less to run each day than your old one. But if you need to replace your old fridge, it pays to choose an energy-efficient model.
Choosing the most energy-efficient medium-sized (376-450L) fridge-freezer we’ve tested would save $119 every year compared with a similarly sized 15-year-old model. Even an averagely efficient new model would save you $85 each year.
A router quietly connects your home to the world at all hours of the day and night. It does this using just 7-8W – that’s an annual cost of $18.22.
Your cordless landline isn’t likely to factor into any unexpectedly large power bills. The Panasonic and Uniden models we’ve tested use no more than a watt, or $2.28, every year.
Charging mobile devices won’t blow your power bill through the roof. Charging a phone like the iPhone 7 from empty every day for a year costs 71¢, while a tablet like an iPad Air, with a much larger battery, would cost $2.66.
And what about the habit of leaving chargers plugged in but not connected to a device? We measured the power use of a few chargers:
Leaving all of these plugged in at the wall costs 15¢ every week, or about $8 each year. It’s not a lot, but it’s all wasted power. If all 1.7 million New Zealand households turned their chargers off when not in use, we might save 1 gigawatt hour of electricity each week.
TIP: It’s easy to tell if your charger is a drain – if it feels warm, it’s using power, so turn it off.
Appliances on standby get a bad rap for needlessly using power. However, while it’s true any power used on standby is wasted, it’s probably not as much as you might think.
We measured standby power consumed by technology and appliances we’ve tested and calculated the best and worst performers over a year.
|Appliance||Lowest ($)[width=medium]||Highest ($)|
|Home theatre system||0.04||0.25|
Some technology products (TVs, Blu-ray players and home theatre systems) cost much less than a dollar each year on standby, no matter the model. A games console will cost you a couple of dollars, regardless of whether you choose an Xbox or PlayStation. However, in the case of some multi-function printers, the power used on standby varies significantly between models, from nothing at all to more than $10 every month.
TIP: The only sure way to kill standby energy use is by unplugging a device or turning it off at the wall when you aren’t using it.
Sky and Vodafone decoders are notorious for using almost as much power on standby as they do while you’re watching Game of Thrones. We found a decoder used 24.3W while in use, and 23.6W while on standby. Switching to standby seems to do little more than switching a blue LED to red. Sky says you shouldn’t turn off your set-top box as it needs to be updated regularly. A set-top box, even if left unwatched on standby all day, would use $53.75 in power each year. Add that to your Sky fee.
Hot water is a big power consumer. A 10-minute shower costs around half the price of a deep soak in the bath. A 5-minute shower is even better. But you should have a water-efficient shower head, or it won’t be as cheap. Our calculations are based on a moderately efficient showerhead. The best heads will cost even less to run.
If you hand-wash dishes then rinse them in hot water, we estimate it’s costing 30c (a 15-litre sink filled twice). To wash and rinse the number of dishes you can load into a modern dishwasher, we think at least 2 lots of wash and rinse water are needed. A good dishwasher can do the job for half the cost – as long as you don’t run it half full.
Tip: Avoid the half-load setting – it usually costs almost as much as a full load.
Most of us already cold-wash clothes, but we’ve done the sums to show how much it costs using warm water. In a large top loading washing machine, the hot water could cost more than that new super-concentrate detergent. If you use a clothes dryer, add another 81 - 99c every time.
Our tables compare typical running costs for a range of appliances with electricity costs of 26c/kWh.
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If you’re shopping for a new whiteware appliance, TV, computer monitor or heat pump, you’ll see an Energy Rating label prominently displayed on the products.
The label shows a simple star rating – the more stars, the more energy-efficient the appliance. The label also features an annual energy consumption (kWh per year), calculated from average expected use.
When comparing models of the same type – for example, small top-mount fridge-freezers – the one with the most stars will be the cheapest to run. But if you’re comparing 2 appliances of different size or type – for example, a small top-mount with a large French-door fridge-freezer – you can’t compare stars and need to use the kWh per year figure to find the cheapest to run.