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Comment by silexia | Hacker News Reader

The Keurig is the worst offender... Enormous energy is expended to keep your water hot 24/7.

Very true - To be honest at the point I knew the house consumption and hadn't yet clamped individual devices I had expected to find a single culprit like that, or even a faulty device with earth leakage that was affectively dumping the current for no real purpose.

I should have also pointed out, I really do wish more devices would have more physical power switches where it makes sense - As an example the washing machine has a touch sensitive main power button, yet our tumble dryer (same manufacture & design) has a more physical on/off switch - The former uses a decent amount of standby power, the second uses none, the only real purpose I see is a slightly more "premium" feel to the washing machine.

Mains power switches are a wear item and can withstand like 10-100x less on/off cycles than a simple button that controls some 3.3V gpio on a microcontroller.

A cheap mains power switch from 30-40 years ago had no problem being cycled once or twice a day for 30-40 years without ever failing. This is not a binding constraint.

Either there's not alot of current going across that switch, or it's just a little lucky - just because that one is going strong doesn't mean over half of the same switch hasn't failed in the same application.

Or, if it's really 40 years old, "cheap" could be "really fat and expensive" today.

If you pick up an old "broken" power (audio) amp, the most likely reason for it to be broken is pots - switch - caps - FETs in that order.

Do you have stats on this? I've developed coffee makers and other appliances. Yes, there's often a mode where the boiler keeps warm for some amount of time after the first cup is made. The first cup can take minutes to heat up, and the second is often much shorter. Then there's a certain amount of time where the preheat is left on, and eventually it's turned off if the coffee maker isn't used again. Different models/makes have different algorithms and modes, but this is a common pattern. There are energy conservation standards which also come in to play, so unless we're taking about a commercial machine, I don't think anything current will just keep the preheat on forever.

I wouldn't have believed it either, and yet:

"Keurig brewers – unless turned off – continuously heat the water inside the heating tank even when the brewer is sitting idle. Some Keurigs such as K-Cafe and K-Elite feature an auto-off function that switches off the brewer two hours after its last brewing to save on energy."

I guess if your machine is trashing the planet with plastic waste anyway, why not also trash it on the energy consumption side? What a disaster.

ref. https://kahawaplanet.com/does-keurig-boil-water-how-to-get-h...

I keep an electric kettle and Melitta pour-over on my desk at work. It is on when I turn it on, then it is off. The Keurig has always seemed like kind of a bad deal.

I guess you could make a case for this kind of thing in a breakroom or something where it's going to be in use all day, but then again, that's also the scenario where it would make the most sense to just be continuously brewing whole pots of coffee in a conventional drip machine.

Either way, a Keurig in a home, only brewing once or twice a day? The worst.

My keurig would keep it hot for weeks. How much energy that actually wasted, I'm not really sure.

I just got one but the Zojirushi hot water dispenser can keep 4 liters of water hot for 31 - 48 watts or so. What does the Keurig use?

https://www.amazon.com/gp/product/B00R4HKIV8/ref=ppx_yo_dt_b...

Zojs are well insulated hot water dispensers, a keurig is a pod-type coffee machine, so I assume it’s just an un-insulated plastic reservoir (though hopefully it doesn’t keep the entire reservoir hot, only the water for the “next dose” for people who can’t cope with waiting 30 seconds for the machine to heat up)

I really wish keurig would just have a big capacitor inside to insta-heat the water beyond what’s possible from mains in real-time. But I guess there’s too much risk of shocky shock.

> I really wish keurig would just have a big capacitor inside to insta-heat the water beyond what’s possible from mains in real-time. But I guess there’s too much risk of shocky shock.

I'm not sure that's an option unless you have a capacitor larger than the device. Heating water takes a lot of energy: let's say we're talking 200mL water (0.2kg), ambient temperature is 20C, water has a specific heat of 4.2kg/kg.C, so that's 67200J.

A Maxwell K2 3000f 3.0v would store a hair under 13500J, which isn't even remotely close, and these things are huge (https://youtu.be/y8tQesYvCig?t=10), heavy (>500g), and each would be a significant fraction of the keurig's existing price.

If you need to strap 5 capacitors to the keurig, danger aside, you've added 2.5kg to the thing, you've strapped a pack twice the size of the brewer, and you've at least doubled and probably close to tripled its price.

My Quooker does too, keep a reservoir permenantly at 110C. It only uses 10W thanks to its insulation though. Surprising Keurig didn't think of that. Then again, they've mostly seemed to have thought about taking your money.

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