Today the energy audit continues to the most important appliance next to the coffee machine. The kettle. As a pommie, I need my tea, so let’s hope this baby isn’t a planet killer…
If you think about it, the traditional kettle sums up our approach to energy for the last 100 years. i.e we waste energy every day because we are too damn lazy to come up with a better way to get a cup full of boiling water. We use resistive heat to boil much more water that we need in a jug with almost zero insulation, and if you are like me you usually end up boiling it twice because between switching the kettle on and it boiling you’ve got distracted so much that the water’s tepid by the time you realize.
That’s the theory what doe s the power meter tell us over 24 hours? Well here’s the plot of Watts vs. time over 24 hours:
Well it looks like my household has 6 cups of tea in a typical 24 hours (click on the image to enlarge and you’ll see six spikes). And 2 of those spikes are thicker because that’s where I boiled it twice as described above.
The accumulator on the power meter tells me that the kettle used 0.52kWh which extrapolates to 190kWh ($30) per year to feed my family’s tea habit.
So what’s the potential for energy efficiency here?
Well the kettle uses no power in stand-by thanks to the switch breaking the circuit when it switches off, so no savings to be made there. But I know that I always boil more water than I need.
My exhaustive research (i.e. 10 minutes on Google) reveals only 2 alternatives:[caption id="attachment_43" align="alignright" width="300" caption="The ecokettle"][/caption]
The eco-kettle and the Tefal Quick Cup both claim energy savings – 31% and 65% respectively. The ecokettle is a neat design where you have 2 chambers – one to store the water – which dispenses a measured amount into a second chamber. The idea being you only boil the water you need. The quick-cup boils the water on demand, a bit like an electric shower. The feedback on Amazon is that the quick cup makes a crap cuppa because the water only comes out at 93 degC. Plus it costs $15 in filters every six weeks! Hmmm, what’s the embodied energy in those?
So I think I’ll invest in an ecokettle. They aren’t available in Australia – so it’s off to ebay.co.uk where I can pick one up for 20 quid. If it saves me 30% then that’s a further 60kWh per year lopped off the bill for a total cost of $100 (20 pounds plus shipping from the UK is another 20 pounds = 40 pounds = $100). I’ll stick the power meter on there when I get it and see if the numbers stack up with Australian water
Stop press: more efficient kettles on the way says the hippy shopper