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idle power consumption class–a vs class–d

Of course, audio gear only represents a small part of total energy consumption, but it all adds up. There are similar mandatory EU standards for other equipment such as televisions, refrigerators or washing machines. In many cases the current models only consume about a quarter of that by their ancestors of some fifteeen years ago. It incentivizes technological innovation and stops manufacturers being lazy.

I bought a new "Energy Efficient" LG Dryer and it's no more efficient than my 25 year old unit. It tries to reduce energy by turning off the heating element but then the load runs twice as long. If you are willing to wait 2x-3x as long you might save 5% in energy but maybe not. As this design is a bit stupid the controls also offer "Manual" mode which costs 5 cents more to run but gets the load dry in 30 minutes instead of 82. It's an energy Ponzi scheme. Luckily, other "Energy saving" devices save more, but a heat pump dryer can never be paid for in energy savings at 3x the purchase price. :facepalm:
 
It's doubtful you will save enough in energy to pay for a new amp solely based on idle power use?
That, of course, depends on local electricity price. If an idling amplifier uses about 50 watts more than a modern efficient one, this adds up to more than 1 kWh a day, or about 400 kWh a year. At current Dutch prices that is about 120 euros a year. So I agree with such prices it probably does not pay for a new amplifier, but at the same time when you are buying a new one anyway, it is worth paying attention to energy consumption. The same is mostly also true for refrigerators, televisions etc.
 
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I bought a new "Energy Efficient" LG Dryer and it's no more efficient than my 25 year old unit. It tries to reduce energy by turning off the heating element but then the load runs twice as long. If you are willing to wait 2x-3x as long you might save 5% in energy but maybe not. As this design is a bit stupid the controls also offer "Manual" mode which costs 5 cents more to run but gets the load dry in 30 minutes instead of 82. It's an energy Ponzi scheme. Luckily, other "Energy saving" devices save more, but a heat pump dryer can never be paid for in energy savings at 3x the purchase price. :facepalm:
I don't know where you are, but the ones in the Netherlands have been tested properly, and heat pump dryers save a lot of energy, and by now don't cost much more. It is true, however, that all these modern washing machines, dryers and dishwashers take rather longer, but who cares? See here for some data: https://energy-efficient-products.ec.europa.eu/product-list/household-washer-dryers_en
 
I measure my "systems" power consumption from time to time with my basic inline power consumption meter. I found an old log from 2021, and here's the results;
  • Emotiva UPA-2 amp power passive bookshelf speakers: idle = 0.8w; on with no music = 32w; on at loud volume = 52w.
  • Yamaha home-theater subwoofer (basic sort): on with no music = 7w; on at normal volume = 8w; on at loud volume = 15w.
Neither is terrible. But perhaps what is "terrible" was the PC I had them connected to! AMD 3900x, X570 mobo, 2x16gb ram, 1xNVME, Nvidia 2080ti, 550W PSU that is apparently "80+ gold", but I feel it's not that good (Corsair TX550M).
  • PC on standbuy, WakeOnLan disabled: ErP enabled = 4.2W; ErP disabled = 2.7W.
  • monitor? (only got standbuy recorded, 27" 1440P = 0.7W)
  • PC playing music + 1 browser playing YT vid + 1 browser scrolling FB = 128Watts!!!!
  • PC playing music + playing game with GPU throttled @ 55% = 288W.
  • PC playing music + playing game with GPU @ 100% = 458W.
I'm pretty sure I've measured my more recent devices such as Kali IN8, but I definitely measured the 15" pro-sub I recently bought;
I immediately wondered about power draw. At idle, 17.5W.
...
whilst listening to music [...] I had to turn it up to -6dB to get it to blip to 18W.

So audio equipment can no doubt consume some power, but a PC can too, and it can be quite unsuspecting. Even if you are running something lowely like a ryzen-5/core-i5, you might be pulling 70watts with it only doing basic desktop things. And don't forget the "display", especially if you're still rocking a plasma TV o_O Meanwhile a mini-PC with something like an Intel N100 CPU can "do the same" @ 10W.
 
In the USA the LG DLE7000W Dryer is $575 in 240v electric.
Model DLHC5502W 7.8 cu. ft. LG Dryer (Heat Pump) is $1699. Now on sale for $1098 at Home Depot.

The LG DLHC5502W heat pump dryer uses approximately 266 kWh per year.
In contrast, the LG DLE7000W uses 850 kWh per year as an average estimate.
Let's start Calculating the difference over 10 years:
LG DLE7000W (conventional): 850 kWh/year * 10 years = 8,500 kWh
LG DLHC5502W (heat pump): 266 kWh/year * 10 years = 2,660 kWh

The DLHC5502W heat pump dryer costs $528 more.
The question becomes what is the electricity savings.
We do three loads of laundry a week. The measured cost is 81 cents per week with the LG DLE7000W
or $42.12 a year or $421.2 over 10 years.

With the DLHC5502W you would expect electric usage to average 0.3129% or 25.35 cents per week
or $13.18 a year or $131.80 over 10 years.

$421.2 - $131.80 =$289.40 electricity savings that you paid $528 10 years ago to achieve.

Does that make sense?
 
Meanwhile a mini-PC with something like an Intel N100 CPU can "do the same" @ 10W.
This is exactly what I did some time ago: an Intel NUC i7 (I needed the performance) replaced an old desktop that consumed some 400 watts. Financially it was certainly worthwhile. The new screen is much larger and better, and nevertheless consumes only half of what the old one did. Such technical innovation is encouraged by the combination of mandatory regulation for the initial push on the one hand , and market incentives for widespread adoption on the other.
 
the heating element
Heating element, lolz. That doesn't sound like a heat pump based model to me. Perhaps whilst purchasing your dryer you have succumb to green-washing?

Anyway, here's a riddle for you - how much does a clothes dryer cost to run during a winter storm in Texas? Answer = $0, because the grid has likely failed :p

riddle.gif
 
now it has turned out that the korsun offers a lot of power and controls the speakers very well, and also relieves the avr, but it consumes a lot of power when there is no signal, i.e. when it is idle.
You could get a smart plug with a remote control to turn on everything (I think some auto turn-off with no load after x time too?). Also, there are plugs that turn on peripherals when they notice a main device is drawing power. It is usually for PCs, but might work for your application too.

If you go round the house doing checking power consumption (with a measuring plug-device), you notice places where electricity is being eaten up. For example, some basic wireless routers consume about 5 or 6 watts at idle, when others more advanced ones can consume 50 watts. 50 watts over years 24/7 can be a lot of money.

Even if you are running something lowely like a ryzen-5/core-i5, you might be pulling 70watts with it only doing basic desktop things.
It is the graphics card that pulls huge amounts of watts, even at idle. A current ryzen or core processor with integrated graphics pulls quite low watts, say 20-40 watts at minimal load (browser with a few tabs).

$421.2 - $131.80 =$289.40 electricity savings that you paid $528 10 years ago to achieve.
You are right, it is all up to personal situation. The US has very low energy costs compared to UK/EU in general. What are your rates per kwh?
 
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In the USA the LG DLE7000W Dryer is $575 in 240v electric.
Model DLHC5502W 7.8 cu. ft. LG Dryer (Heat Pump) is $1699. Now on sale for $1098 at Home Depot.

The LG DLHC5502W heat pump dryer uses approximately 266 kWh per year.
In contrast, the LG DLE7000W uses 850 kWh per year as an average estimate.
Let's start Calculating the difference over 10 years:
LG DLE7000W (conventional): 850 kWh/year * 10 years = 8,500 kWh
LG DLHC5502W (heat pump): 266 kWh/year * 10 years = 2,660 kWh

The DLHC5502W heat pump dryer costs $528 more.
The question becomes what is the electricity savings.
We do three loads of laundry a week. The measured cost is 81 cents per week with the LG DLE7000W
or $42.12 a year or $421.2 over 10 years.

With the DLHC5502W you would expect electric usage to average 0.3129% or 25.35 cents per week
or $13.18 a year or $131.80 over 10 years.

$421.2 - $131.80 =$289.40 electricity savings that you paid $528 10 years ago to achieve.

Does that make sense?
Sure, this is how to do the sums, although the lost interest should be added to the investment cost as well. The picture changes with different prices, however: over here heat pump dryers are not that much more expensive: a high end model from the best and most expensive brand (Miele) costs 1250 euros: Miele TSF 763 WP EcoSpeed Miele do not seem to make anything other than heat pump dryers anymore. Another major brand, Bosch/Siemens, are cheaper at 850 euros, and also only seem to have heatpump dryers. Both the Miele and the Bosch dryer have the best EU energy efficiency classification (A+++). So at EU prices (incl 21% Value Added Tax) modern heat pump dryers are now cheap and universal. That is good news because our electricity is expensive, currently at about 0.30 per kWh, unless of course you have solar panels.
 
You are right, it is all up to personal situation. The US has very low energy costs compared to UK/EU in general. What are your rates per hour?

10.46 cents per KWh in winter
13.86 cents per KWh in summer
 
Hi, hope this is not too off topic.
What is starting to interest me is the heat implication of higher idle power and the effect on component lifetime. Those Watts have to go somewhere - heat - so are components designed for that heat?
Specifically, are the cheaper Class D amps designed for that heat? I'm calling out 'cheaper' examples as they are more likely to want to reduce component costs and I'm thinking about Class D since they are cooler in operation and thermal management may be focussed on operating (short term) heat rather than idle (long term) heat.
Any thoughts?
 
About 1/4 to 1/3 of our prices. Lucky you!

What we are seeing is with more solar panels and electric cars, electric prices are being hiked by utility providers especially the flat hook up fee which is now being proposed for a 50% increase.
 
What we are seeing is with more solar panels and electric cars, electric prices are being hiked by utility providers especially the flat hook up fee which is now being proposed for a 50% increase.
Do you have a standing charge per day? We have daily standing charges of 50p going up to 62p for electricity soon. My gas usage is very minimal, I think I actually pay more for the standing charge than the gas itself. :oops:
 
Do you have a standing charge per day? We have daily standing charges of 50p going up to 62p for electricity soon. My gas usage is very minimal, I think I actually pay more for the standing charge than the gas itself. :oops:

I don't have a "standing" charge for natural gas. BUT the fees are getting crazy. Here's an example:
Gas System Service Charge = (connect fee). $20.24
Usage Charge (G1.1) $4.30
Natural Gas Supply Cost Adjustment $2.55
Total Taxes $2.25
Total Gas Charges $29.34

As you can see, in a month I only used $4.30 of natural gas yet they charged $29.34. Basically, 6x my actual use.
I moved all my furnaces to heat pumps. The only appliance I have on gas is the water heater. I would like to get a
heat pump water heater and disconnect gas but the heat pump water heaters are $2800.
I have 10 years of warranty left on my gas water heater.
I'll need to wait for tax credits and/or rebates that make it an affordable option.
 
In the USA the LG DLE7000W Dryer is $575 in 240v electric.
Model DLHC5502W 7.8 cu. ft. LG Dryer (Heat Pump) is $1699. Now on sale for $1098 at Home Depot.

The LG DLHC5502W heat pump dryer uses approximately 266 kWh per year.
In contrast, the LG DLE7000W uses 850 kWh per year as an average estimate.
Let's start Calculating the difference over 10 years:
LG DLE7000W (conventional): 850 kWh/year * 10 years = 8,500 kWh
LG DLHC5502W (heat pump): 266 kWh/year * 10 years = 2,660 kWh

The DLHC5502W heat pump dryer costs $528 more.
The question becomes what is the electricity savings.
We do three loads of laundry a week. The measured cost is 81 cents per week with the LG DLE7000W
or $42.12 a year or $421.2 over 10 years.

With the DLHC5502W you would expect electric usage to average 0.3129% or 25.35 cents per week
or $13.18 a year or $131.80 over 10 years.

$421.2 - $131.80 =$289.40 electricity savings that you paid $528 10 years ago to achieve.

Does that make sense?
The calculations are correct. Based on my experience, expecting the dryer to last 10 years is overly optimistic... ;)
 
Don't forget about the planned obsolescence of a new heat pump dryer. Good luck getting a control board 10 or 15 years from now. So now you have to get an entire new dryer instead of fixing it.

My old school top load washer and front load gas dryer are 30 years old. Why would I even contemplate thinking about getting something "modern" if I had to replace them?
 
Don't forget about the planned obsolescence of a new heat pump dryer. Good luck getting a control board 10 or 15 years from now. So now you have to get an entire new dryer instead of fixing it.
This is the farcical aspect of new, "environmentally friendly" products. They are often only environmentally friendly compared to building a new product, in the old way, from scratch, but If an older product works, then the excess energy made to produce it (often higher than it will consume in its lifetime) is already accounted for. Any costs in running it compared to a new product must outweigh the initial cost for a new product, add in the often shorter lifespan of the newer product and all is not what it seems.

If products were truly environmentally friendly, then they should come with a 25 year warranty and some, economically feasible, way of fixing the item should the company go bust. There should be legislation and infrastructure to back up the warranty, so that an item should be repaired by some entity.

Will 90% of the active speakers running today (or class D amps generally) be anything other than landfill in 15 to 20 years time?

It is all a bit robbing Peter to pay Paul. A game of musical chairs around a flimsy concept of 'environmentally friendly'.
 
The calculations are correct. Based on my experience, expecting the dryer to last 10 years is overly optimistic... ;)

My previous dryer lasted 25 years and was still running when we replaced it.
I made the stupid assumption that a 25 year newer "Energy Star" Dryer would save energy.
The new dryer doesn't save any energy and can take 3x longer to dry clothes.
Lesson learned: Keep your old dryer as long as possible.

Our electric company allows us to view hourly energy usage so it's easy to compare both models electricity used for the same amount of work. That's the one nice feature our electric provider offers.

Besides Air Conditioning, the Dryer can be one of the biggest energy users in a household.
 
The table gives you just that: idle power consumption. And as for sound quality, do you know of a controled double blind test that shows sonic differences?
Your previous post had 2 clickable links - I clicked the SINAD table. This shows no idle power consumption figures as far as I can see. It has only these column headings:

THD+N
(5W, 4 ohms)
SINAD (dB)
(5W, 4 ohms)
Power (W)
(1% THD+N, 4 ohms)
Price (USD)Source

The other link is to a thread generally discussing Class D "efficiency", started with an apparently ill-informed opinion. I've not found a table there, just contributions from members offering a few examples - mostly about non-Class D amps, illustrating that these amps are far less efficient. Have I missed a useful table? Thanks
 
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