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Re:No, you can’t save £30 per year by switching off your “st... by D13Fd on Wednesday April 27, 2022 @08:39AM (#31179117)
Yeah. The author is way off here.

Another way you can quickly find big offenders is by using an infrared camera. I found various things in my house that are putting off a ton of heat when doing nothing (and using electricity to do it). My 10-year-old speakers with a built-in amp, for example, absolutely glow on infrared even when sitting there inactive 98% of the time. Now they are on a switch.

Re:No, you can’t save £30 per year by switching off your “st... by m_eiman on Wednesday April 27, 2022 @08:49AM (#31179208)
While an IR camera is a good tool (and terribly fun to use!), not everyone has one. Almost everyone has another tool that can be nearly as efficient though: a hand.

It's quite easy to use too: if something is warm when you touch it, it's burning through watts. If you expected it to be sleeping, it's either not sleeping or it's very bad at it. Don't forget the AC adapters, they can be worse than the devices they supply.

Re:No, you can’t save £30 per year by switching off your “st... by chrisBob on Wednesday April 27, 2022 @12:15PM (#31181903)
My local library has them available to check out for free! The payback period for buying a Flir camera to do your own energy audit is likely long, but checking one out is pretty reasonable.
Re:No, you can’t save £30 per year by switching off your “st... by sidewndr46 on Wednesday April 27, 2022 @09:46AM (#31179826)
In a net heating environment, this is less of an issue than otherwise immediately obvious. A small idle electronic device making a consistent amount of heat just helps heat the house. If electricity is very expensive it would make sense to try and track down the offenders however.
Re:No, you can’t save £30 per year by switching off your “st... by m_eiman on Wednesday April 27, 2022 @09:59AM (#31179959)
Hopefully you have another heating system that's more efficient than direct electricity, though!
Re:No, you can’t save £30 per year by switching off your “st... by denton-scratch on Wednesday April 27, 2022 @10:12AM (#31180115)
How can any electric heating system be more "efficient" than an inefficient appliance? Inefficiency in an electrical appliance is nothing more than a measure of how good that appliance is at turning electricity into heat.
Re:No, you can’t save £30 per year by switching off your “st... by jseutter on Wednesday April 27, 2022 @10:34AM (#31180395)
I had this same thought at one point and eventually learned of heat pumps. Heat pumps move heat from one spot to another, ie from outside your house to inside your house, or the other way. The point is, they move more energy than they consume. So that 1kwh of energy turned into heat by an inefficient electrical appliance could have instead been used to move 5kwh worth of heat into your home by a heat pump.

Heat pumps are more efficient than they used to be (at some point the outside air is too cold for them to work efficiently), so the cold climate where I'm from is just now starting to see them included in new homes.

Re:No, you can’t save £30 per year by switching off your “st... by denton-scratch on Wednesday April 27, 2022 @03:27PM (#31184630)
Yes, I've considered getting a heat pump; for one reason and another, I can't.

It doesn't feel right to talk about the "efficiency" of a heat pump system; talk of "1W in gets you 3W out" isn't right, because you didn't magic those 3W out of thin air. It's more like "4W in gets you 4W out". It seems wrong to say that a heat pump system is "400% efficient".

I thought efficiency was a measure of how much of the work[0] going into a machine is transformed into the intended output work. I suppose you could say that this heat delivery machine is inefficient if a lot of the input work is expended on producing torque, or raising heavy stuff. But even that eventually turns into heat; just in the wrong place.

[0] I hope I'm using "work" and "machine" in the technical sense, so that "work" means displacement against a force, and a "machine" is any device for converting work from one form to another. Effiency is well-defined for that kind of machine: it's just the ratio of work in to work out, the output being what you want; so "efficiency" intrinsically depends on what your intentions are for your machine. .

Re:No, you can’t save £30 per year by switching off your “st... by Sohcahtoa82 on Wednesday April 27, 2022 @06:14PM (#31186502)
> It doesn't feel right to talk about the "efficiency" of a heat pump system; talk of "1W in gets you 3W out" isn't right, because you didn't magic those 3W out of thin air. It's more like "4W in gets you 4W out". It seems wrong to say that a heat pump system is "400% efficient".

Those 3W didn't come out of thin air, it came from outside air.

1W of energy going into the heat pump causes 4W of heat energy to get moved from outside your house to the inside of your house.

That's the key thing to take note of. Traditional resistive heating works by turning electrical energy into heat energy directly. Heat pumps move heat energy the same way an A/C unit does, it just moves it the other way.

Essentially, a heat pump is just an A/C unit with the evaporator and the condenser flipped.

Re:No, you can’t save £30 per year by switching off your “st... by zarzavat on Wednesday April 27, 2022 @05:44PM (#31186196)
All heaters are 100% efficient in a closed system. However, your house is not a closed system. It’s a spatial region of an open system. In this context it makes sense to talk about efficiency as being lower or greater than 100%.
Re:No, you can’t save £30 per year by switching off your “st... by _carbyau_ on Thursday April 28, 2022 @01:10AM (#31188967)
I wish this were made evident to the hoteliers with bar fridges kept in sealed cupboards...
Re:No, you can’t save £30 per year by switching off your “st... by systoll on Thursday April 28, 2022 @12:43AM (#31188818)
> you didn't magic those 3W out of thin air.

No magic, but you are pulling those 3W out of the outside air.

You can use the industry term 'Co-efficient of performance' to avoid any possible ambiguity, but it's just the same thing with a different name.

Re:No, you can’t save £30 per year by switching off your “st... by Freestyler_3 on Wednesday April 27, 2022 @04:07PM (#31185080)
The efficiency is higher than input because the electricity is only used to transfer heat from one spot to another. This is when the gas gets compressed, to get to the condensing stage at the high pressure. (+after burn for optimal efficiency)
Re:No, you can’t save £30 per year by switching off your “st... by shagie on Wednesday April 27, 2022 @10:55AM (#31180664)
Another one of my "came across this in YouTube" things (started with the design of a hurricane lantern) Why Heat Pumps are Immensely Important Right Now - https://youtu.be/MFEHFsO-XSI

The key is the Coefficient of performance https://en.wikipedia.org/wiki/Coefficient_of_performance

Re:No, you can’t save £30 per year by switching off your “st... by sp332 on Wednesday April 27, 2022 @10:37AM (#31180431)
If your electricity comes from natural gas, it would be more efficient to burn the gas on-site for heat than to burn it to generate electricity, distribute the electricity, and then turn it back to heat.
Re:No, you can’t save £30 per year by switching off your “st... by totoglazer on Wednesday April 27, 2022 @12:25PM (#31182070)
Most efficient to burn the gas for electricity and use that to power a heat pump.
Re:No, you can’t save £30 per year by switching off your “st... by sidewndr46 on Friday April 29, 2022 @10:30AM (#31205630)
It'd be far simpler and more efficient to use a reciprocating engine to drive a heatpump via a rotating shaft. As a bonus, you could capture the exhaust from the engine with a heat exchanger and use that to heat the house as well.
Re:No, you can’t save £30 per year by switching off your “st... by shagie on Wednesday April 27, 2022 @10:58AM (#31180713)
Yes...ish.

However, consider the greater performance scales with generators combined with the amount of useful heat that one gets out of a heat pump can be better than converting the natural gas to heat locally - even with losses on the grid.

The key is that a heat pump doesn't convert electricity to heat (as a resistive heater) but rather moves heat from one spot (outside) to inside with great efficiency.

Re:No, you can’t save £30 per year by switching off your “st... by sp332 on Wednesday April 27, 2022 @11:02AM (#31180755)
Yes, but the comment I'm replying to is about resistive heating from inefficient appliances.
Re:No, you can’t save £30 per year by switching off your “st... by KiranRao0 on Wednesday April 27, 2022 @10:28AM (#31180318)
A heat pump. Instead of using power to heat a room, you're using a (relatively) small amount of power to move heat from outside into the room.
Re:No, you can’t save £30 per year by switching off your “st... by electroly on Wednesday April 27, 2022 @10:38AM (#31180438)
The others mentioned heat pumps but I'll mention that the person you replied to never said "electric" and is likely referring to gas heating.
Re:No, you can’t save £30 per year by switching off your “st... by markus92 on Wednesday April 27, 2022 @10:18AM (#31180186)
A heat pump?
Re:No, you can’t save £30 per year by switching off your “st... by mort96 on Wednesday April 27, 2022 @01:25PM (#31182988)
In addition to what other people are saying, there's also district heating: https://en.wikipedia.org/wiki/District_heating Heat can be generated efficiently in some centralized location (from geothermal heat, power plant waste heat, solar, or whatever) and then distributed to nearby homes.

There's lots of ways to heat homes in ways which use way less than 1 joule of electricity for 1 joule of heat.

Re:No, you can’t save £30 per year by switching off your “st... by sidewndr46 on Wednesday April 27, 2022 @10:41AM (#31180484)
If you had a heat pump, it would be more effective to run that for sure.
Re:No, you can’t save £30 per year by switching off your “st... by _Algernon_ on Wednesday April 27, 2022 @12:11PM (#31181831)
How can heating be inefficient?
Re:No, you can’t save £30 per year by switching off your “st... by robonerd on Wednesday April 27, 2022 @03:02PM (#31184323)
Besides the matter of heat pumps which others have covered, there is also the matter of how good your heating system is at getting heat to where you actually need it.

A PC under your desk will keep your toes warm, and maybe with warm toes you don't really mind the rest of the house being at 10 C / 50 F. With such space heater, you can turn down the thermostat for the entire house and only heat the parts you care about most. Furthermore there are radiative space heaters which direct infrared energy to a specific part of the room using a reflective dish, instead of heating the entire room using convection. In large rooms, radiative space heater can keep you feeling warm while using much less energy than a heatpump would require to heat the whole room.

Re:No, you can’t save £30 per year by switching off your “st... by mort96 on Wednesday April 27, 2022 @01:32PM (#31183099)
By generating only 1 joule of heat per 1 joule of electricity used. There are lots of much more efficient ways to heat homes.
Re:No, you can’t save £30 per year by switching off your “st... by londons_explore on Wednesday April 27, 2022 @10:16AM (#31180160)
In most of the world electrical heat is about 3x as expensive as the next cheapest heating (gas, coal, oil, heat pump or wood)
Re:No, you can’t save £30 per year by switching off your “st... by PaulHoule on Wednesday April 27, 2022 @10:01AM (#31179991)
In the summer though heating the house is a bad thing. Either you are making your house hotter or you're making the air conditioner work harder to remove it.
Re:No, you can’t save £30 per year by switching off your “st... by esaym on Wednesday April 27, 2022 @10:30AM (#31180366)
Even better, just go to a pawn shop or ebay and get a used current clamp meter for cheap. Then pull the cover off of your circuit breaker box in your house and check the current draw on each and every wire.
Re:No, you can’t save £30 per year by switching off your “st... by giantrobot on Wednesday April 27, 2022 @02:16PM (#31183715)
> Almost everyone has another tool that can be nearly as efficient though: a hand.

I've found the IR camera works much better than my hand for things like switching power supplies. They'll be glowing in IR while being cool to the touch even when no device is plugged into them. While each might not be a ton of power I tended to just leave them plugged in all the time.

Re:No, you can’t save £30 per year by switching off your “st... by quietbritishjim on Wednesday April 27, 2022 @08:54AM (#31179248)
Speakers are notoriously a specific case where power actually does get used in standby, so it doesn't really contradict the original article. For instance, an old BBC News article (not the one published today that probably triggered this submission) listed "TV on standby" as using lots of power but was actually including various peripherals including powered on external speakers. I would expect turning those off and leaving the TV on would use almost no power. If, as parent comment says, even the TV/monitor is using significant power, then that's a lot more interesting.
Re:No, you can’t save £30 per year by switching off your “st... by D13Fd on Wednesday April 27, 2022 @02:04PM (#31183557)
It may be a specific case, but then the article title should be "No, you can’t save £30 per year, unless you happen to have speakers like most people..."

But there are other things around as well. My old laserjet printer was another offender.

Re:No, you can’t save £30 per year by switching off your “st... by dspillett on Wednesday April 27, 2022 @09:44AM (#31179801)
> I would expect turning those off and leaving the TV on would use almost no power

That is going to vary a lot depending on the TV. I suspect a lot of modern "smart" TVs consume a measurable amount when idle.

Re:No, you can’t save £30 per year by switching off your “st... by maccard on Wednesday April 27, 2022 @10:17AM (#31180176)
Idle or in standby? EU regulations state the maximum standby power is 0.5w.
Re:No, you can’t save £30 per year by switching off your “st... by madaxe_again on Wednesday April 27, 2022 @12:34PM (#31182201)
You do, however, typically need to set “low power standby” or whatever in the options somewhere - it’s usually not enabled by default - the default is usually to turn the screen off but leave everything else running. Mine drew about 5W in “normal” standby, and is immeasurably low (from our household inverters - I live off grid) in low power standby. It takes about 10 seconds to boot - no big deal.
Re:No, you can’t save £30 per year by switching off your “st... by nsteel on Wednesday April 27, 2022 @03:04PM (#31184352)
I believe the low power mode is required (by UK law, at least) to be enabled by default. It's pointless otherwise as almost nobody will go and enable that mode.
Re:No, you can’t save £30 per year by switching off your “st... by scarby2 on Wednesday April 27, 2022 @02:26PM (#31183832)
> You do, however, typically need to set “low power standby” or whatever in the options somewhere - it’s usually not enabled by default

i had the opposite, i had to disable the low power standby (which was on by default) so i could wake it over the ethernet or via HDMI-CEC

Re:No, you can’t save £30 per year by switching off your “st... by outworlder on Wednesday April 27, 2022 @01:21PM (#31182925)
I've thought about buying an infrared camera, but I've found them to be terribly expensive. Not in scientific terms as they are precision instruments, but in 'I have some money to spend on amazon but this thing has high three figures so I'll buy something else'. Specifically talking about FLIR and the direct competitor I forgot the name.

Are there any affordable cameras that are not completely trash? Low resolution is ok.

Re:No, you can’t save £30 per year by switching off your “st... by D13Fd on Wednesday April 27, 2022 @01:38PM (#31183194)
Mine is an HTI-19 320 x 240 resolution one that was $233 on Amazon. It's not cheap, but I've certainly saved more than that in electricity from problems it identified in the 2.5 years since I bought it. It works just fine.

An infrared camera is great for tracking down and fixing insulation problems in your house, if you own a home. And fixing insulation issues really brings down your heating/cooling bills.

If you don't own a home the value proposition is a lot worse, but $200 or so still isn't bad for something that amounts to a fun toy.

EDIT: Sorry, it was $380 before Amazon points. I should have clicked into the invoice.

Re:No, you can’t save £30 per year by switching off your “st... by gehwartzen on Wednesday April 27, 2022 @01:45PM (#31183302)
The FLIR One or Pro are in the $220-300 range if I remember correctly. They attach to your iphone and use that as the screen an maybe for some processing. In any case it works pretty well for most personal applications you might run across.
Re:No, you can’t save £30 per year by switching off your “st... by corobo on Wednesday April 27, 2022 @05:09PM (#31185843)
Hypothetically speaking you could buy one, find the hot spots, send it back to Amazon.

Morally it’s not exactly solid but at least you’re not standing on the backs of the poor to be a billionaire and all that

Re:No, you can’t save £30 per year by switching off your “st... by edent on Wednesday April 27, 2022 @08:47AM (#31179188)
Really depends where in the world you are. In the UK / EU there are rather strict rules on how much power devices can use in standby.
Re:No, you can’t save £30 per year by switching off your “st... by abandonliberty on Wednesday April 27, 2022 @10:50AM (#31180586)
I have electrical heating, so until the summer there's no such thing as wasted electricity.

Many people struggle to understand this concept. In some climates and energy grids, switching from things like incandescent to LED causes a greater environmental impact. It may shift (and may have already) as LED production gets more efficient.

Re:No, you can’t save £30 per year by switching off your “st... by ejolto on Wednesday April 27, 2022 @11:08AM (#31180834)
You should read up on heat pumps, they are several times more efficient than electrical resistance heaters.
Re:No, you can’t save £30 per year by switching off your “st... by abandonliberty on Thursday April 28, 2022 @01:48AM (#31189158)
26% of heating in Canada is electric baseboard, much of it in buildings that can't or won't allow heat pumps. https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=381002...

Even for those who can, it would take several years for the investment in a heat pump plus the waste of the old heating system to become carbon neutral, let alone cashflow positive.

Don't feel bad. This entire thread is filled with people who think they know better. Must be why UX is in such high demand these days.

I get the enthusiasm though, head pumps are really neat.

Re:No, you can’t save £30 per year by switching off your “st... by madaxe_again on Wednesday April 27, 2022 @12:36PM (#31182226)
Depends on what other value you get from your “heater”. My PC, running at full whack, draws about 700W, which all gets radiated as waste heat. It’s enough to maintain the temperature in my (well-insulated) living room when it’s 20C colder outside.
Re:No, you can’t save £30 per year by switching off your “st... by outworlder on Wednesday April 27, 2022 @01:25PM (#31182989)
Still inefficient, but I guess that's power you were going to draw anyway.

You sure it's drawing 700W? Are you running multiple GPUs or what? Is that a server? Have you measured?

Re:No, you can’t save £30 per year by switching off your “st... by buildbot on Friday April 29, 2022 @01:07PM (#31207832)
That's kinda the point though, that heat is doing work anyway, and they may not have the ability to use/install a heat pump. Of course it would be more efficient, but for example, my condo has three separate electric wall heaters. Instead of using them, we just rely on our computers to heat our space enough. Works until it is about 4-5C outside.

Someday if I ever get to build a custom house, I plan to install a full 42U rack that is tied into the houses central air to optionally heat the house with the waste heat.

Re:No, you can’t save £30 per year by switching off your “st... by BizarroLand on Wednesday April 27, 2022 @01:57PM (#31183460)
Also, if your rig goes over, say, 400 watts of power it is definitely worth it to get an 80+ efficiency rated power supply. There are quite a few tiers, bronze, silver, gold, platinum, titanium, etc., but that's the equivalent of extra 9's uptime where just the 80+ rating is the first 99%
Re:No, you can’t save £30 per year by switching off your “st... by kemotep on Wednesday April 27, 2022 @03:36PM (#31184729)
I doubt they use a non-80+ power supply with their modern high end CPU and GPU seeing as the standard was introduced in 2004, with Energy Star certification requiring it in 2006.

But not only is the efficiency rating important but the specific model’s efficiency curves at cold loads and hot loads, 20%, 50%, and 100% loads. Paying attention to your components and what level of power usage they will be at for most of their usage will dictate what the most efficient specific model of power supply (at a reasonable price point for you). This of course makes reviewing and purchasing power supplies quite complicated.

Re:No, you can’t save £30 per year by switching off your “st... by BizarroLand on Wednesday April 27, 2022 @05:42PM (#31186178)
My personal experience has been that people skimp on the power supply, it's the one area where direct performance isn't affected so the features that the power supply provides are not directly correlated to the overall performance of your machine.

Many people, especially in mid-tier or lower builds where every dollar for price vs performance has been calculated to the decimal point will opt for the cheapest power supply that meets the wattage and connector requirements their particular build requires, efficiency and longevity be damned.

My opinion is that getting a guaranteed 80% power conversion efficiency rating (as compared to, say, a 75% conversion efficiency rating) on a 500 watt PC will save you 25 watts of power over the years that you use it, plus a manufacturer that actually goes through the process of getting the approval will probably have also put a little extra care into their manufacturing process and so probably has a better reliability rating than one that did not.

Unless you are scraping to get any PC together it may well be worth an extra $10 in price variance, all other things being equal, for that piece of mind and minor electricity savings to boot.

Re:No, you can’t save £30 per year by switching off your “st... by kemotep on Wednesday April 27, 2022 @06:15PM (#31186508)
My point was, in the past few years I have been buying computers, I have never seen a non-80+ psu. Not that they do not exist, certainly there are unlabeled white boxes for dimes and nickels on the dollar compared to a quality one.

I went out of my way to research my current power supply to make sure that given my usage and components, it would operate in peak efficiency (I believe mine is at nearly 95% efficiency at average load, would need to measure it more thoroughly, it has been a few years).

I feel a power supply is like tires. They are the only thing that actually touches the road(electricity). They are worth paying for something halfway decent, not bottom of the barrel.

I do agree, but I would be shocked to see a non-80+ psu at a reputable store like Micro Center.

Re:No, you can’t save £30 per year by switching off your “st... by BizarroLand on Thursday April 28, 2022 @04:52PM (#31198053)
True. It's been about 5 years since I built a new computer and so my information apparently is a little but outdated, but a quick search through newegg's cheapest power supplies shows things like this:

https://www.newegg.com/p/1HU-0027-00010?Item=9SIAXE5EGG6813&...

650 watt, no-name non-80+ power supply for $40. That's the sort of thing I'm talking about. There are 80+ rated power supplies in the same price range or 80+ from reputable companies for $10 more but it's still a thing worth looking for when you're a newish builder or if you have any concern for the overall efficiency of your computer.

After all, base 80+ rating still means that for every watt your PC actually gets to use you're converting .2 watts directly into heat. That's not a big deal for a workstation that may only draw 100 watts under load but if you have a beefy PC with 3090s and an overclocked 12 series i9 processor with a lot of fans, you could be burning 100 watts or more just to power the thing, so it would definitely be worth it to go for gold or platinum 80+ rating just to save the money in waste heat and in cooling that waste heat after the fact.

Re:No, you can’t save £30 per year by switching off your “st... by madaxe_again on Wednesday April 27, 2022 @02:06PM (#31183582)
RTX3080 and a 12 core i9-12. Yeah, I’m obsessive about power consumption as we’re off-grid - it’s more like 650W at peak, when running a modern game at 4K on maximums. Doing nothing much it draws about 50W.
Re:No, you can’t save £30 per year by switching off your “st... by outworlder on Wednesday April 27, 2022 @03:38PM (#31184751)
Got it. Only reason I asked is that I've seen crazy figures thrown around (specially when PSU sizing) that never matched reality - specially when you look at the claimed cooling solutions. Dissipating 700W is no small feat.
Re:No, you can’t save £30 per year by switching off your “st... by madaxe_again on Thursday April 28, 2022 @02:25AM (#31189319)
Particularly as I have it on a mini-itx, in a cupboard - the radiator lives outside the case, outside the cupboard. It’s actually proven dead handy, as the weather gets too warm for running the log stove, but too cold at night to not have any heating - so using the waste heat from entertainment to keep the place cosy seems like an efficient approach.
Re:No, you can’t save £30 per year by switching off your “st... by danans on Wednesday April 27, 2022 @02:46PM (#31184120)
> In some climates and energy grids, switching from things like incandescent to LED causes a greater environmental impact.

But for a huge number of people (probably the majority) who live in more temperate climates (most of Europe and the US), they are a net win both in their energy bills and environmentally marginal extremely cold climates. That's the people whom LEDs target, not the people in marginal extreme cold climates running high power-draw servers in their homes.

Re:No, you can’t save £30 per year by switching off your “st... by david422 on Wednesday April 27, 2022 @10:55AM (#31180660)
> In some climates and energy grids, switching from things like incandescent to LED causes a greater environmental impact

How would that be the case?

Re:No, you can’t save £30 per year by switching off your “st... by nybble41 on Wednesday April 27, 2022 @11:39AM (#31181350)
If you live in a climate where it's too cold for heat pumps to function, and rely on electrical (resistive) heating instead, the "waste" heat from the incandescent bulbs offsets the power needed for heating almost 1:1. Replacing those with LED bulbs wouldn't reduce your power requirements at all (you'd just run the heaters more) and the LEB bulbs require more energy and exotic materials to manufacture.
Re:No, you can’t save £30 per year by switching off your “st... by brnt on Wednesday April 27, 2022 @12:49PM (#31182442)
Is there such a thing as too cold for heat pumps though? They drop in efficiency, sure, but still beat resistive heating. Modern ones are still going to be 300% efficient down to -20C or so. With a resistive pre heater I don't see how they'll ever not be more efficient than resistive heating.
Re:No, you can’t save £30 per year by switching off your “st... by BizarroLand on Wednesday April 27, 2022 @01:59PM (#31183485)
My heat pump is a Trane heat pump from 2018 and it goes into emergency heat mode when the temps are below 36, which is off and on for most of the winter. I wonder if I should have it serviced to make sure it's working correctly.
Re:No, you can’t save £30 per year by switching off your “st... by bcrosby95 on Wednesday April 27, 2022 @02:43PM (#31184074)
It's partially a function of your heating demands. My sister's emergency heat mode would run all the time in her town house. But she installed a giant insulating curtain over one of her leaky sliders and now it almost never needs to run.
Re:No, you can’t save £30 per year by switching off your “st... by BizarroLand on Friday April 29, 2022 @01:25PM (#31208118)
That seems more like she improved her insulation, decreasing her heating needs rather than addressing the temperature cutoff for a heat pump.

I still like the heat pump because in the summer my power bill for cooling a 2600 sq ft home is about $50/month, and in the winter I do have a wood burning stove that I can run to heat the house when the temps are below 36. That and recirc mode on the fan unit can keep my power bills to a minimum.

Re:No, you can’t save £30 per year by switching off your “st... by nybble41 on Wednesday April 27, 2022 @04:13PM (#31185146)
A heat pump with a sufficiently powerful resistive preheater will be at least as energy-efficient in operation as the resistive heater alone, but it's also much more complex, with a correspondingly higher up-front cost and ongoing maintenance requirements. A resistive heater can consist of little more than a solid-state heating element, a blower fan, and a mechanical thermostat; radiative heaters can even dispense with the fan, which is the least reliable part of the system. A heat pump, by contrast, additionally involves pumps, heat exchangers, and volatile fluids under pressure, generally under the management of some moderately complex logic.
Re:No, you can’t save £30 per year by switching off your “st... by brnt on Thursday April 28, 2022 @05:36AM (#31190473)
Naturally a heat pump is more complex and thus more maintenance intensive, but it's worth the investment/cost in energy savings in any calculation I've seen (they do tend to require more maintenance).
Re:No, you can’t save £30 per year by switching off your “st... by nybble41 on Thursday April 28, 2022 @10:58AM (#31193257)
Cost is one factor, but if you live in, say, rural North Dakota, you may not be able to afford the risk that your main source of heat breaks down in the middle of a blizzard and you can't get anyone in to service it for several days… or weeks. Don't discount the value of predictable reliability.
Re:No, you can’t save £30 per year by switching off your “st... by outworlder on Wednesday April 27, 2022 @01:30PM (#31183058)
> If you live in a climate where it's too cold for heat pumps to function

Year round? So you mean the polar regions? Because they can work even at -10F. Efficiency is reduced, but they can work. Crappy ones will cutoff earlier though. If you are not in one of the planet's poles, we have seasons so it's better to use LEDs for at least 3/4 of the time (maybe more as even northern latitudes only have a few really severe winter days).

Modern LED lamps are tiny and use very little material. Incandescent bulbs are no longer considered 'exotic' because of how old the tech is, but tungsten was a very exotic material at some point.

Re:No, you can’t save £30 per year by switching off your “st... by fencepost on Wednesday April 27, 2022 @02:05PM (#31183560)
If you live in a climate where it's too cold for heat pumps to function, and rely on electrical (resistive) heating instead

That's the point where I'd strongly consider cryptocurrency mining.

Re:No, you can’t save £30 per year by switching off your “st... by gigel82 on Wednesday April 27, 2022 @11:15AM (#31180929)
Reminds me of the story of the LED traffic lights that freeze in winter, thus needing an additional heating solution (making them more expensive / error-prone and even less energy-efficient during cold weather): https://www.popularmechanics.com/technology/infrastructure/a...
Re:No, you can’t save £30 per year by switching off your “st... by gregable on Wednesday April 27, 2022 @11:28AM (#31181177)
That was once true but it's no longer a real issue: https://youtu.be/GiYO1TObNz8
Re:No, you can’t save £30 per year by switching off your “st... by jhugo on Wednesday April 27, 2022 @11:10AM (#31180863)
5x 100W light bulbs is 0.5kW of heat output which your heating system doesn't need to supply.

Switch to LED and your heating system will need to supply that extra 0.5kW.

In a climate where you are almost always running heating, this makes the benefit of switching to LED much smaller, and considering that they are much less environmentally friendly to produce, it may even tip the scale the other way.

Re:No, you can’t save £30 per year by switching off your “st... by gregable on Wednesday April 27, 2022 @11:34AM (#31181267)
Yes, but. There are few places that need heating 100% of the year and fewer people living there. During the non-heating hours/days, that's just waste heat.

Depending on where the bulbs are located, they may be emitting into a ceiling cavity that exits the building's envelope more quickly than the location of the heating coil. Some bulbs are actually outside the building.

And of course, the heating system can supply 0.5kW for less than 0.5kW of power with heat pumps or (net including generation and transmission) natural gas.

Re:No, you can’t save £30 per year by switching off your “st... by D13Fd on Wednesday April 27, 2022 @01:50PM (#31183372)
This really only applies where the heat is frequently so low that heat pumps cannot function. Antarctica, or maybe Siberia or northern Alaska.

Beyond that, heat pumps are still much more efficient than direct electric heating.

Also, if you have air conditioning at any point in the year, those incandescent lights are just going to make your air conditioner work that much harder.

Re:No, you can’t save £30 per year by switching off your “st... by post-it on Wednesday April 27, 2022 @11:44AM (#31181430)
Resistive electrical heating is typically the most expensive heating option available, at least here in Canada. A heat pump uses much less power to provide the same amount of heat, and fossil fuel heating (gas in the west, oil in the east) is often much less expensive than electric.
Re:No, you can’t save £30 per year by switching off your “st... by aperson_hello on Wednesday April 27, 2022 @11:14AM (#31180923)
It used to be the case. The energy cost of production was massively higher in their early days and if the waste heat was used, there wasn't a net energy savings. Not so much anymore, especially when increased lifespan is taken into account (it's at least at parity at this point).
Re:No, you can’t save £30 per year by switching off your “st... by jahewson on Wednesday April 27, 2022 @01:18PM (#31182871)
Your amp isn’t “doing nothing” it’s just… on. Just because you’re not feeding it a signal doesn’t mean it’s not amplifying.