Some thoughts on LED status indicators

[ayayay!]

Power used:
An adapter is marked with the maximum power it CAN put out, not what it uses. All adapters have a technology that is (as noted above) approximately energy in = energy out. If the adapter is unloaded, no, it does not sit there and eat up its full rating internally. It puts out only what it being used plus the small fraction used to start it up and keep it going, as noted above.

OK I'm so close...  I can smell it. 

R. G. would you indulge me now and put a load on what you said above?  What's now being lost? 

[flo]

If you're trying to save energy, it's best to figure out where the most energy is going and make a small reduction in that, rather than trying to eliminate tiny ones. And in fact, there is the potential to save much, much more than you might attacking the tiny ones.

True but usually, the "tiny ones" are under my control and I can actually eliminate them now with little efford and some discipline.

Whenever I leave the office where I work I walk by our server room, filled with computers consuming a vast amount of energy and aa cooling system that tries to keep the room temperature down while  nobody is using them because all employees are at home, not working anymore. Every time I wish for a "full stop" button that I could punch to shutdown these servers.
The only thing I can control is the R&D department where I work and make sure all computers and small "local" servers" that we use are shutdown with monitors fully powered down (not in standby).

it's always going to be wanting to give 300mA, is it not?

Like R.G. also stated, its only going to provide what is being asked by the attached device that it needs to power. The power rating is what can potentially/maximally can provide.

[flo]

put a load on what you said above?  What's now being lost?

Only some power due to inefficienty of the adapter is lost, the heat that it generates.

[ayayay!]

Okay so the adapter itself is really only losing what the pedal calls for.  I get that.   Is the energy that it hasn't used from that availalbe pool of current being dissipated as heat?  Or is it not being spent and it truly is saving energy? 

[flo]

the adapter itself is really only losing what the pedal calls for. 

Not really: The adapter itself is only providing what the pedal "asks" for + some small power loss due to inefficienty.

Is the energy that it hasn't used from that availalbe pool of current being dissipated as heat?

No, that energy is just not used at all because nothing "asks" for it.
Only the energy that is "lost" due to inefficienty is dissipated as heat which is usually less that 5% of the total potential power that adapter could provide (if an attached device asked for it).

Or is it not being spent and it truly is saving energy?

Indeed, it's not being spend because nothing "asks" for it. So you could say that it is "saving energy".

[Heemis]

Well it looks as though this thread accomplished a bit more than it set out to, and we all learned something (except the people who already knew)

I could go on all day about the wasting of energy.  As I already mentioned previously, all my gear is connected to a switched power conditioner, and that thing is off when I'm asleep and at work (so, roughly 75% of my time  ).

So the verdict is, if you reduce the power consumption of your pedal, you will be drawing less current when using a power adapter.  But for pete's sake, unplug the adapter when you're not using it!

[R.G.]

True but usually, the "tiny ones" are under my control and I can actually eliminate them now with little efford and some discipline.

What does that tell you?

Whenever I leave the office where I work I walk by our server room, filled with computers consuming a vast amount of energy and aa cooling system that tries to keep the room temperature down while  nobody is using them because all employees are at home, not working anymore. Every time I wish for a "full stop" button that I could punch to shutdown these servers.
The only thing I can control is the R&D department where I work and make sure all computers and small "local" servers" that we use are shutdown with monitors fully powered down (not in standby).

If there really is no one using them, not employees working remotely instead of driving in to work, not testing programs, and not serving the organization's web sites or 24 hour sales, and not data backup/maintenance routines to keep the data available, then yes, you could, with no loss to the org shut them down. Most forward-thinking organizations give some kind of reward for saving a lot of money.

The AC is not trying to keep the air temperature down. It's pumping the waste heat from the servers outside. If this was not done, the temp would go up and the servers would fail, both in immediate errors and in reduced life for the power components.

[R.G.]

R. G. would you indulge me now and put a load on what you said above?  What's now being lost? 

When you put a load on a power supply, the load current flows. The power spent is the product of the voltage and the load current. There are fixed and variable losses inside the adapter. The fixed losses are usually equal to the no-load power drain. The variable losses are a result of the load current's heating things up before it goes to the load.

So the total is Ptot = Pfixed + Pvariable + Pload. Pload is what the adapter rating plate tells you.

[R.G.]

I could go on all day about the wasting of energy.  As I already mentioned previously, all my gear is connected to a switched power conditioner, and that thing is off when I'm asleep and at work (so, roughly 75% of my time  ).

Yes. Wasting energy is really a bad thing to do. We should all do some simple, straightforward things, like not driving cars, not riding in a vehicle powered by fuel, leaving the AC or heating off, not using electricity, not eating any foods which have to be hauled to us from more than 100 miles away, and other little things in our control

[oskar]

Power Adapters:
All power adapters use some power when plugged in. In almost all cases this is a few percent of the full-load power they can provide. There are two types of these adapters, those being (a) 50 or 60-Hz transformer based and (b) switching power supplies. The power line frequency units (a) may run as much as 5% of full load power or as little as less than 1%.

Good news...  

On a purely engineering level, this is amazing. Very few electronic devices and no mechanical devices convert as much as 95% of their input energy into output. The switching versions (b) are even better. They can be designed to use much less than 1% of the full load power when under no load. In its quest for perfect greenness, the state of California has now made the under-5% version illegal to sell, demanding the switching version regardless of cost and regardless of the increased monetary price, higher EMI emissions, higher embedded energy, and rare/toxic materials used in making switching power supplies to replace iron and copper. But I do have to admit, calling it "Vampire Power" is a cool political slogan, isn't it?

That really sucks. Energy/environmental issues must be discussed in a much bigger frame (I'm getting stuck on english words here...)
Discussing LED's in stompboxes is an interesting exercise but if you eat vegetarian food once a year, you possibly save the energy your "blinkenlicht" passion is craving. (Meat production is that much more energy intensive)

Or to save it somewhere else.

I've got to admitt, I don't see guitar effect units as a big problem area, no...    

So the verdict is, if you reduce the power consumption of your pedal, you will be drawing less current when using a power adapter.  But for pete's sake, unplug the adapter when you're not using it!

But you will use a lot less than my examples off course. Still I wote: unplugg...

But I still haven't figured out how much more stagelight I need to power my solar Tubescreamer?  
And all this excess thinking is actually using up energy to...

[space_ryerson]

In the IT realm, there is a lot going on these days in terms of consuming less power in the server room. When your CFO gets a power bill of $10k a month, he will start asking 'what can you do about this?'. Blade server enclosures can have dynamic allotment of power to the blades. This can cut 30% power consumption when compared to an equal number of standalone individual servers. With virtualization (such as VMWare), several 'servers' that were used intermittently can live on one 'physical server', and will sit hibernating until called upon for use. This is great for lesser used servers, but obviously not good for things like domain controllers, web servers, mail servers, etc. This cuts down the number of physical servers needed to be run.

A new one I saw last week was in a server co-location facility. They offered greatly discounted pricing on renting racks powered with DC, as opposed to AC. The way I understand it is that you would use DC power supplies on your servers, and since there's no AC to DC conversion, a lot less heat is expelled from the machines. Pretty interesting.

[flo]

True but usually, the "tiny ones" are under my control and I can actually eliminate them now with little efford and some discipline.

What does that tell you?

That I feel like a tiny nobody without any real power to make an effective change on my own... (oef, that is kinda depressing)

[Heemis]

I could go on all day about the wasting of energy.  As I already mentioned previously, all my gear is connected to a switched power conditioner, and that thing is off when I'm asleep and at work (so, roughly 75% of my time  ).

Yes. Wasting energy is really a bad thing to do. We should all do some simple, straightforward things, like not driving cars, not riding in a vehicle powered by fuel, leaving the AC or heating off, not using electricity, not eating any foods which have to be hauled to us from more than 100 miles away, and other little things in our control

A man after my own heart.  Luckily I live in New York City, and because of that, I have many opportunities to save energy.  I do not own a car, I ride a bike or the subway, I don't use AC in my home, i'm a big fan guy, and I have lots of access to good local food... and on that note:

Discussing LED's in stompboxes is an interesting exercise but if you eat vegetarian food once a year, you possibly save the energy your "blinkenlicht" passion is craving. (Meat production is that much more energy intensive)

oskar, I am actually a vegetarian, and the reason is the environmental impact of meat production. 

[davent]

High up on my list of wanted tech stuff is a power meter. They're not expensive and you can find out instantly what your TV/stereo is consuming when you think it's off.

Our local library loans out Kill A Watt meters. Was interesting going around the house seeing how much energy various pieces of equipment was using,( including the things that are supposedly shut off.)  The important things 18watt amp was using ~60 watts, my stereo ~100watts.  http://www.p3international.com/products/special/P4400/P4400-CE.html

dave

[ayayay!]

Special thanks to Oskar and R.G. for indulging me.  It's not that I didn't "get" or was over-thinking it, but I genuinely saw an angle I hadn't thought of before, so thanks for clearing that up.

I'm also in IT, and one cool new way I've seen drastic heat reduction is to face rows of equipment back-to-back, so that the heat is shot out twice as strongly on every other aisle, and to put the Liebert (cooling unit) intakes directly over those aisles.  As any HVAC technician will tell you, a compressor has to pick up heat somewhere to effectively cool, so that it can exchange it in the condenser and expand the coolant more effectively when the time comes on the return loop. 

Another thing is phone switches.  Anything older than this decade is usually using a ridiculous amount of power, especially for stacked switches.   Dial tone generators, backup shelves, supervisory engines...

A Cisco VoIP switch uses about 1/10th the power and has 10 times more processing power than a typical Nortel switch (did anyone notice they went bankrupt last week?)  Not to mention VoIP uses far less voltage over the lines to the desktop, and Nortel/Lucent/whomever uses anywhere from 24 to 70 volts every time you take the handset off the cradle.  Sure PoE switches are using 48V, but they're on the same ports as the ethernet so you're still eliminating a lot of hardware.   

[waltk]

Nice discussion... here's a perspective I didn't see anywhere in it.  While everyone agreed that "wasting" energy is a terrible thing (on a macro or micro scale), I'm thinking that any excess heat dissipated by any device (toaster ovens, power tools, amps, effect pedals, or even a single LED) in my house is not being wasted.  It's the middle of winter here in Pennsylvania, and any heat produced by inherent inefficiencies in my devices is reducing the amount of time my furnace is running to heat my house.  And it doesn't matter how much or how little inefficiency is involved.  Because the physical laws concerning conservation of energy, I'm getting the benefit of any inefficiency in the form of household heat.   ...of course, the converse is true in the summer - when the inefficiencies in my devices contribute to the thermal load that my air conditioner must then remove.

I'm not trying to argue in favor of waste or inefficiency - just trying to put forth the notion that discussions like this are usually bounded by some implicit domain like "my wallwart and effect", or "my house", or "my planet".

[space_ryerson]

Another thing is phone switches.  Anything older than this decade is usually using a ridiculous amount of power, especially for stacked switches.   Dial tone generators, backup shelves, supervisory engines...

A Cisco VoIP switch uses about 1/10th the power and has 10 times more processing power than a typical Nortel switch (did anyone notice they went bankrupt last week?)  Not to mention VoIP uses far less voltage over the lines to the desktop, and Nortel/Lucent/whomever uses anywhere from 24 to 70 volts every time you take the handset off the cradle.  Sure PoE switches are using 48V, but they're on the same ports as the ethernet so you're still eliminating a lot of hardware.   

I'm in the beginnings of a Cisco VoIP implementation, moving from....a Nortel system!