Efficiency

[HiTech]

Well, FWIW here are a couple of web sites that claim 100% efficiency!

**broken link removed**

**broken link removed**

http://www.energysystemsanalysts.com/direct.htm

**broken link removed**

http://en.wikipedia.org/wiki/Energy_efficiency

 

[Hero999]

Yes, you've guessed it I am clueless I have never needed to learn about supercooling a 1GVA transformer before.

 

[xrunner123]

I'm new and just joined so I'll chime in. Transformers can be very efficient.
The latest power supply design under my belt is a 2.5Kw, 400V to 48v with an overall efficiency of 94%. There are 2 switchmode transformers used with each one dissipating approx 10W. Doing the math, this equates to a transformer efficiency of 99.2%

 

[Helloween]

100% efficient devices? Easy!

Step 1. Assume a perfect world...

 

[Hero999]

That's an interesting project could you please post the schematic?

I take it you're using 3 phase, are you using a conventional 6 pulse rectifier design or are you going for a more harmonic reducing, power factor factor correcting 12 or even 24 pulse design?

 

[xrunner123]

That's an interesting project could you please post the schematic?

I take it you're using 3 phase, are you using a conventional 6 pulse rectifier design or are you going for a more harmonic reducing, power factor factor correcting 12 or even 24 pulse design?

Sorry I cannot post schematics.

It's made for a PFC output so the input voltage range in 300-400VDC.
Its a switchmode ZVS design, freq is 120khz or so.

 

[Hero999]

Why, it it a project for work and therefore proprietary information?

 

[RODALCO]

As already said before the bigger transformers are usually more efficient. say 100 KVA or bigger can easy achieve an efficiency of 95% or higher.

As in the kettle example it is nearly 100% efficient in using the power taken of the mains.
Say you have to allowe for some volts drop in the wiring from your kWh meter to the socket, some losses in the "scraping contacts" of the plug, then the lead and the IEC connector at the base or "cordless" contacts

a 2000 Watt kettle element is probably 98% efficient in transferring the absorbed power from the mains to the water in the kettle.

 

[Helloween]

a 2000 Watt kettle element is probably 98% efficient in transferring the absorbed power from the mains to the water in the kettle.

Speeding up entropy always tends to be easy. It's harder to convert one form of energy into something that ends up as something other than heat.

Newton's balls in a vacuum would do a pretty good job of converting kinetic to potential energy and vice versa.

 

[Roff]

Speeding up entropy always tends to be easy. It's harder to convert one form of energy into something that ends up as something other than heat.

Newton's balls in a vacuum would do a pretty good job of converting kinetic to potential energy and vice versa.

My son got his lip in a vacuum once, and it turned fat and purple.

 

[Hero999]

I don't think Newton would be too happy if you put his balls in a vacuum!

 

[Nigel Goodwin]

I don't think Newton would be too happy if you put his balls in a vacuum!

Wouldn't care, he's been dead for years!.

 

[dknguyen]

Wouldn't care, he's been dead for years!.

That's easy to say when it's not your corpse they are messing with!

 

[Oznog]

A heater resistor is pretty much 100% efficient at turning electrical power into heat, especially on DC so electromagnetic radiation is not a factor. So if you consider wire losses up to the resistor itself to not be part of the resistor's losses, I'm not sure what losses are possible if you count IR radiation as part of the product.

That could be described best as just being an extremely simple task, rather than the resistor being some super-effective technology.

 

[Nigel Goodwin]

That's easy to say when it's not your corpse they are messing with!

Seeing as he's been dead 279 years (had to check on google!), I doubt 'corpse' could be applied to him? - I also doubt there's much left to 'swing in a vacuum'

 

[spuffock]

If it's not 100% efficient, the losses end up as heat. If a heater were not 100% efficient, what would happen to the losses?
THINK ABOUT IT.

 

[dknguyen]

If it's not 100% efficient, the losses end up as heat. If a heater were not 100% efficient, what would happen to the losses?
THINK ABOUT IT.

It does produces EMR (necessarily light, but it's possible). Any amount of EMR produced would make it not 100% efficient, due to the strict nature of the definition. Like the nice glowing elements in a stove.

Also, I am not sure, just throwing it out there, but if something expands because of heat, doesn't that require some kind of energy loss?

 

[Nigel Goodwin]

If it's not 100% efficient, the losses end up as heat. If a heater were not 100% efficient, what would happen to the losses?
THINK ABOUT IT.

Perhaps you ought to?, the heater is trying to supply heat to the load - it will make losses everywhere else as well, the leads feeding it, the switches, the connectors, even the generator that originally supplies the power for it!.

 

[akg]

If it's not 100% efficient, the losses end up as heat. If a heater were not 100% efficient, what would happen to the losses?
THINK ABOUT IT.

i think you missed a part . efficiency is output/input . but what is the output , its the energy which is availabe for your actual use . a heating coil dissipates power as heat and sometimes light, you wont be able to use the FULL heat o/p due to radiation/conduction/convection . Yes with carefull effort u can acheive max efficiency like a thermaly sealed water heater .