Battery Power Our Systems?

The power packs for satellites were based in tiny amounts of radioactive material.
The radiation hazard is terrible. And it is less green, in the sense it does not give out the same amount of power that went into making it, uranium mining and purification needs lots of energy, and the small satellite packs need hazmat handling all through their production.

Weather permitting, a combined solar / wind installation, combined with peak shaving battery charging, is the most suitable at this time.

The interference comes from the step up converters (reversed SMPS), used to generate AC at mains voltage from lower voltage DC sourced from battery.

In a purely DC amplifier, and with the lights also on DC (use LED sources), this can be avoided.
Fans, now BLDC is common, HVAC still needs mains, at least to my knowledge.
 
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I have been running my stuff off batteries off and on. I came across some designs that I share here:

https://www.tnt-audio.com/ampli/rocksolid_e.html

https://www.amazon.com/DIFIIFOL-Battery-Bluetooth-Amplifier-JT-30BBT/dp/B07DXP1ZVN

https://darko.audio/2013/12/red-wine-audio-signature-57-integrated-amplifier-review/

Apparently Red Wine is no longer selling the above unit, going for capacitors instead. Capacitor power our systems or are they already?

https://www.stereonet.com/forums/topic/86331-red-wine-audio-folded-their-tent/

The designer is however producing some sterling products

https://www.vinnierossi.com/collection/

My impression is that the design for a specific listening time should make sure the loss of battery charge should be as slow as possible within the limits of the amplifiers maximum and minimum voltage? Is this correct?

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...

The designer is however producing some sterling products

https://www.vinnierossi.com/collection/

...

What Rossi is doing nowadays is to run two packs of supercapacitors in parallel.

He charges one pack off a DC external brick while he uses the other one. The trick is how to switch between them on the fly without being detectable.

I think it's a great idea if I could have a big battery providing the DC to charge the supercaps.

He can get enough juice to run his 25wpc integrated amp, which is class AB. I wonder how many caps would be required to run something line an Aleph 2.
 
I have been doing some research on this subject for a hifi setup in my truck camper and from what I understand so far the problem with the battery is voltage sag under load otherwise known as power supply impedance. Could a step down regulator stabilize the voltage ? But how does one design an ultra quiet high current stepdown regulator ? Maybe any regulator noise wouldn't matter if the amp had a well designed CRC filter. Definitely an interesting subject.
One way to think of the power amplifier is that it's a giant linear regulator, programmed with an audio signal. Dealing with sag is already part of its job.

If a class A amp has a CCS, apart from acting like a negative resistance, it filters out the audio as seen from the line, and it could be a good option despite drawing lots of power. If it's push-pull, the line can be loaded down with audio and lots of harmonics, depending on the overall design.

One nice thing about batteries is that you're not stuck with just ONE. But if there are lots of them, then recharging could be a project in itself, with a bank of relays and Raspberry Pi to control them all, or something like that.
 
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Here in SoCal... we can get an electric Time Of Day Rate to charge storage batteries. Idea being that you charge the batteries at night time when the grid load is small and the cost is very low.

This can be done irrespective of solar panels.

Typical such battery would be from 17.5 to 20 KwH. Cost is around $20K installed. Two such batteries would give me ~40KwH with 60A... so I could use one to power the freezer, fridge. The other one I could run to the TV, home network (so I can watch my Plex Servers) and a few lights (all LEDs) and stereo. Everything is on nice, dedicated home runs so it would be very easy to do.

That way I could run the A2s which put out 400 wpc each, just sitting there. I figure when I run the stereo with the A2s I'm using close to 1KwH. The one piece of the home network that likely takes the most power is the ethernet and 801.11ac bridges.

..

Class A... yep... it always uses its rated power, whether running or not, huh? So it's gonna be Vcc - F(i, b) where F is a voltage function based on the input and the circuit bias. When the input is 0, then we have the idle condition. Since the average voltage of the input is 0, meaning it puts out as much power on the + and it does on the - side, we see that the average power used by the Class A circuit will be its dissipation at the idle condition. Please correct me if I'm wrong.

A Class AB circuit is quite different since it's idle condition is very little power. So the power usage of an AB circuit will vary with the input signal.

That means I can easily plan for power usage of a class A circuit, but not for a class AB. Except that the AB will always use less power than A.
 
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Well... A tiny amount of Uranium could power our systems for many years. Completely off the grid and night friendly.
Then there is gravity powered storage. A great alternative to battery storage, as is flywheel storage.

Gravitricity launches gravity energy storage pilot in India

https://www.pv-magazine.com/2022/11/29/gravitricity-launches-gravity-energy-storage-pilot-in-india/

Gravity-based batteries try to beat their chemical cousins with winches, weights, and mine shafts

https://www.science.org/content/art...mical-cousins-winches-weights-and-mine-shafts


Concrete flywheel storage system for residential PV

Currently, Energiestro offers a standard storage solution with a nominal power of around 10 kW, which corresponds
to a charge and discharge cycle in one hour

https://www.pv-magazine.com/2021/06/21/concrete-flywheel-storage-system-for-residential-pv/
 
Grid balancing for gravity storage, the idea is to raise the weights using power at times when the grid is lightly loaded, and using it to generate power at peak hours.

The underlying concept is that steam plants need time to build up and go off load, that can be in hours, so by reducing the load variation, the plant runs at nearer optimal conditions.

Some states here tell the steel plants to do their melting at night, and roll / cast the melt as quickly as possible, but that can be done in the day. Arc furnaces need enormous amounts of power, induction furnaces use less (mostly they use smaller capacity crucibles).

There is no free power involved.
Good idea, but over 50 years it will need lots of safety maintenance..
 
For energy efficiency in QRP conditions, (Radio term for low power), Class D with efficient speakers is ideal, but the sound quality...your opinion counts.

Hydro power stations also have an option of using grid power to raise water from down stream to storage, it is called pumped storage, again an old concept.
Some of these concepts are being revisited because there are energy shortages, and high costs because of that.

New Zealand has some steam power plants running on geo-thermal sources, steam comes out of the ground. No fuel is needed except for emergency use.
But in an apartment in Toronto, you can't do much by yourself, have to depend on grid power.
 
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We had a solar + battery system at home, and it would run for about 2 hours, including the fridge. Any amplifier plugged in would then be running off batteries. It may be better to run the entire home off DC . I like the sound of it.

The results depict DC system to be better than AC system with an efficiency advantage for 3.88% and 3.62% for bulk and separate PEC topologies respectively.

AC vs. DC Home: An Efficiency Comparison


https://ieeexplore.ieee.org/document/8887064

DC driven refrigerators are also available as well as the "DC GENERATOR"

I wish I had known of this earlier:

iGen160s Portable Power Station

"Can charge up to 9 devices at a time that can power up to 40-hours of lights, 3-hours of TV, 14 smartphone charges, 3 laptop charges, 6 drone charges, and 2 nights on select CPAP devices"
How do You bring it back to the top without consuming energy ?
Use solar energy to take it to the top. Unwind at night.
 
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Let me see if I understand...
When You release the weight it generates energy. How do You bring it back to the top without consuming energy ? Manual Crankshaft ?

The idea is to store the power when it is cheap ( at night ) and release it when it is expensive ( during the day ). Raise the mass to store potential energy.

Using a mass that is dropped slowly running a generator with a pulley is not all that efficient since you need to use brakes to control the descend of the mass. Brakes waste energy.

Using water that is pumped up and then released through a variable area orifice and then drives a turbine is a lot more efficient since it doesn't require brakes to control the downward movement of mass.
 
With mass on a pulley, the electric load could be calculated / buffered to provide the right amount electric braking. But yeah, water is more versatile. No big landing thump at the end. Also, the base load could driven directly without the losses from charging and discharging batteries.

I always wondered why they never make home gym set-ups with proper generators. No market for it?
 
Maybe because we make very little power. Not many watts.
A bicycle dynamo was a load as a child.
Treadmills, maybe.

But people will do things to bend your mind.
Like the guy who told customer care your computer coffee holder will not come out...he thought the CD drive was a cup holder....!

Actually, a small DC motor can be used to make a small windmill, they are called 'bicycle windmills'
But even those are too big a load for most humans.

Maybe an old turn table DC motor can be rigged to a treadmill, or exercise cycle, to charge cell phones or whatever.
Car alternator...I don't think so. Heavy load.
 
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When I was young and fit (many centuries ago, lol) I measured the road gradient and calculated that I could produce about 1kW in short bursts for a few seconds while cycling a up a steep hill. So 100W is definitely more sustainable. But most small DC motors make awful generators. The absolute best generator I've ever come across was from a VCR, probably because the low spin speed was a good match for manual charging.
 
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My son bought himself a Power Bank... I think it puts out 1300 wh or something like that.

He got it so he could power his guitar amp in the woods... he was able to play with his band out in a park whenever they wanted...

But at this point, you start to pay some serious money.

OK... less than $20K for the 20KwH power bank... but still.... hmm....
 
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With mass on a pulley, the electric load could be calculated / buffered to provide the right amount electric braking.
A few years ago I invested in a gravity powered lantern for places with no electric grid. A weight dropped spinning a small generator to power the LEDs. Of course it was actually human powered, and the weight was the storage.
I dunno what ever happened to that project.