How "efficient" is electron transport as an energy medium?

[SunnyD]

I'm curious, because there have been rather few "high-tech" improvements to the way we harness and use energy over the years. How efficient is electron transport compared to other methods? And better yet, will we (humans) ever be able to harness raw energy rather than have to convert it into some more (currently) usable form like electricity? Are there any current advancements underway in this field?

Off the top of my head, the only alternative methods we have for harnessing energy almost all equate with turning them into electricity, almost all through a mechanical means - meaning there's got to be a lot of loss going across the energy production for that method. The only one I can think of that isn't a mechanical device would be photo-electrical generation (solar panels).

As far as alternative energy usage, about the only thing that comes to mind is steam or water power, but those have generally fallen by the wayside or adapted to accommodate mechanical-electrical production (turbines). Even nuclear reactors - capable of giving off so much raw energy - still convert it into a mechanical form which is then turned into electricity.

I'd be curious to see if mankind ever manages to move away from "electricity" as the predominant form of energy. I'm also curious to know how much energy is lost in the various methods we have to generate electricity today.

 

[Howard]

A lot of our devices use electricity, so why not? It's also a lot easier to transfer electrical energy than chemical, kinetic, thermal, etc.

 

[So]

Originally posted by: SunnyD
I'm curious, because there have been rather few "high-tech" improvements to the way we harness and use energy over the years. How efficient is electron transport compared to other methods? And better yet, will we (humans) ever be able to harness raw energy rather than have to convert it into some more (currently) usable form like electricity? Are there any current advancements underway in this field?

Off the top of my head, the only alternative methods we have for harnessing energy almost all equate with turning them into electricity, almost all through a mechanical means - meaning there's got to be a lot of loss going across the energy production for that method. The only one I can think of that isn't a mechanical device would be photo-electrical generation (solar panels).

As far as alternative energy usage, about the only thing that comes to mind is steam or water power, but those have generally fallen by the wayside or adapted to accommodate mechanical-electrical production (turbines). Even nuclear reactors - capable of giving off so much raw energy - still convert it into a mechanical form which is then turned into electricity.

I'd be curious to see if mankind ever manages to move away from "electricity" as the predominant form of energy. I'm also curious to know how much energy is lost in the various methods we have to generate electricity today.

Okay, you desperately need a physics class before you think any more about this. Your working definition of energy seems to have more to do with a new-agey touchy-feely concept of energy rather than the real world physical concept of energy -- the ability to do work.

 

[Kntx]

It would be cool if instead of wires we had this weird system of ropes and pulleys. Imagine these constantly spinning clothes line looking things strung between utility poles. It would be squeaking all the time too.

 

[Crono]

What about light? I'm guessing if you can minimize heat loss with efficient optical fiber, you could use it to carry energy (and not just data as we do now)? Probably would take new technologies and materials to carry it long distances with minimal loss, though.

 

[SunnyD]

Originally posted by: So
Okay, you desperately need a physics class before you think any more about this. Your working definition of energy seems to have more to do with a new-agey touchy-feely concept of energy rather than the real world physical concept of energy -- the ability to do work.

If I'm not mistaken... we use electricity in a form that allows us "to do work". And I'm not talking about turning on the lights and letting us sit in an office pushing papers either.

Thanks for the inference that I'm physics illiterate, but I've got it down. Electricity, or rather electron transport is the method we use most to manifest a (currently) usable form of kinetic/potential/etc. energy. What I'm asking is if there's anything on the table that can potentially reduce the number of energy state changes and/or more-directly utilize the actual energy from a given source rather than continually converting it into electricity.

 

[artikk]

I'm not that physics literate either but I honestly don't see other alternatives-maybe light. But then how it's going be utilized to do work confounds me.Also, I'm thinking forces such as magnetism, gravity, and nuclear forces are only others left as having the potential for work. Gravity is weak over great distances, so that' s not really a go for macro/micro utilization on Earth(besides mechanical uses), and the others too. Honestly, electricity is much more manageable than the alternatives.
Also, if one switches the medium, the entire infrastructure has to be redesigned if one's goal is to be one source(energy/work transport) system vs combining different energy transport sources. All the transistor circuits, etc would be useless with the redesign for the former option.
I wish we could use fusion already.

 

[CoachB]

If I'm understanding the question right (which is highly doubtful) you are talking about packaging and transport of energy...not the generation thereof. As far as I know electrical and microwave are the most effective transport methods going when one considers energy loss and ease of transport.
In most cases, you MUST have a change of state to perform work (such as turning a motor or lighting a bulb). Isn't that part of the definition of work..a change of state??

 

[So]

Originally posted by: SunnyD

Originally posted by: So
Okay, you desperately need a physics class before you think any more about this. Your working definition of energy seems to have more to do with a new-agey touchy-feely concept of energy rather than the real world physical concept of energy -- the ability to do work.

If I'm not mistaken... we use electricity in a form that allows us "to do work". And I'm not talking about turning on the lights and letting us sit in an office pushing papers either.

Thanks for the inference that I'm physics illiterate, but I've got it down. Electricity, or rather electron transport is the method we use most to manifest a (currently) usable form of kinetic/potential/etc. energy. What I'm asking is if there's anything on the table that can potentially reduce the number of energy state changes and/or more-directly utilize the actual energy from a given source rather than continually converting it into electricity.

Lights are very much "doing work" and transporting energy from one place to another is most efficiently done with electricity for a variety of reasons, from low losses to the ease of converting the power to a form that you need at the moment. Electricity is *not* "electron transport", which is a biological term, nor is it the movement of electrons, it is the propogation of an electric (and associated magnetic) field in a conductive medium. There are losses in converting energy from one form to another, but electricity is by FAR the safest, simplest and lowest loss method of moving energy from one place to another. The only other method that anyone has come up with would be to burn natural gas at the location and use it directly, but the lower efficiencies of smaller motors versus big power plants would mostly make up for the savings from electrical losses. There is nothing materially bad about "changing" your energy from a less useful but more transportable form to a more useful but less portable one.

 

[SunnyD]

Originally posted by: So
Lights are very much "doing work" and transporting energy from one place to another is most efficiently done with electricity for a variety of reasons, from low losses to the ease of converting the power to a form that you need at the moment.

Way to kill the joke.

However, I thought most of our current methods of transporting electrical energy are extremely lossy, particularly if we want to transport it any large length of distance. Due to particulate motion, we're always bleeding energy in terms of heat. I'm not sure what percentage is lost however, since it's not my field. I'm sure there are other losses involved, particularly in processing the energy along the way to it's final destination.

Electricity is *not* "electron transport", which is a biological term, nor is it the movement of electrons, it is the propogation of an electric (and associated magnetic) field in a conductive medium.

Alright, I'll give you the confusing terminology - but electrical current is essentially the transport of electrons across a medium (in most cases - though it can potentially be any charged particle, but most often electrons).

Originally posted by: So
There is nothing materially bad about "changing" your energy from a less useful but more transportable form to a more useful but less portable one.

I agree... with exception of the losses involved in doing so.

 

[AyashiKaibutsu]

Originally posted by: artikk
I wish we could use fusion already.

What do you think we'd do with Fusion besides boil water with it to turn turbines? This threads all about how energy is moved so changing how it's generated won't change that.

 

[yoda291]

if my childhood is accurate -- and it is -- the most efficient storage medium for energy is energon cubes.

that is all.

 

[SunnyD]

Originally posted by: yoda291
if my childhood is accurate -- and it is -- the most efficient storage medium for energy is energon cubes.

that is all.

You know what's funny... that's the absolute first thing I thought of when I began to contemplate this very question.

 

[Freshgeardude]

energy is never whole. you can never get the complete amount. laws of thermodynamics. transferring to electricity may be the most efficient because eventually it all would be converted to electricity for appliances etc. if they change it early, less energy would be loss if they keep it electric.

 

[So]

Originally posted by: SunnyD
However, I thought most of our current methods of transporting electrical energy are extremely lossy, particularly if we want to transport it any large length of distance.

Not really, yes they are lossy, but that can be fixed, it just costs more up front to reduce the losses on the back end.

Due to particulate motion, we're always bleeding energy in terms of heat. I'm not sure what percentage is lost however, since it's not my field. I'm sure there are other losses involved, particularly in processing the energy along the way to it's final destination.

It *is* my field, and there are of course losses, but you're not going to find a way to make losses go away. Electrical equipment is fairly close to carnot efficieny limits (i.e. ideal).

Alright, I'll give you the confusing terminology - but electrical current is essentially the transport of electrons across a medium (in most cases - though it can potentially be any charged particle, but most often electrons).

No, it's not. You really seem to be just slinging around terms you've heard without a good grounding in the science behind it. Electron drift speed is different from the phenomenon we use to move power electrically.

Originally posted by: So
There is nothing materially bad about "changing" your energy from a less useful but more transportable form to a more useful but less portable one.

I agree... with exception of the losses involved in doing so.

Losses due to "converting" energy from electrical to mechanical and vice versa are *very* low and efficiencies have quietly been improving and approaching the ideal since the beginning of the twentieth century. There are losses, but those losses are dictated by the laws of thermodynamics.

 

[DrPizza]

Not sure if you're going to do better, but you could do worse - you could convert chemical/nuclear energy into mechanical energy into electrical energy into hydrogen which you then use in a fuel cell to convert it back to electrical energy & finally mechanical energy in a car.

Alternately, we could invent fusion reactors that weigh about 1000 pounds and are easily transportable. Then, to power vehicles, we could convert nuclear energy more or less directly into mechanical energy to drive our vehicles.

 

[GodlessAstronomer]

Originally posted by: So

Originally posted by: SunnyD
I'm curious, because there have been rather few "high-tech" improvements to the way we harness and use energy over the years. How efficient is electron transport compared to other methods? And better yet, will we (humans) ever be able to harness raw energy rather than have to convert it into some more (currently) usable form like electricity? Are there any current advancements underway in this field?

Off the top of my head, the only alternative methods we have for harnessing energy almost all equate with turning them into electricity, almost all through a mechanical means - meaning there's got to be a lot of loss going across the energy production for that method. The only one I can think of that isn't a mechanical device would be photo-electrical generation (solar panels).

As far as alternative energy usage, about the only thing that comes to mind is steam or water power, but those have generally fallen by the wayside or adapted to accommodate mechanical-electrical production (turbines). Even nuclear reactors - capable of giving off so much raw energy - still convert it into a mechanical form which is then turned into electricity.

I'd be curious to see if mankind ever manages to move away from "electricity" as the predominant form of energy. I'm also curious to know how much energy is lost in the various methods we have to generate electricity today.

Okay, you desperately need a physics class before you think any more about this. Your working definition of energy seems to have more to do with a new-agey touchy-feely concept of energy rather than the real world physical concept of energy -- the ability to do work.

That's not at all how I interpreted the OP, not sure where you're getting that from.

 

[PlasmaBomb]

Originally posted by: SunnyD
Alright, I'll give you the confusing terminology - but electrical current is essentially the transport of electrons across a medium (in most cases - though it can potentially be any charged particle, but most often electrons).

Have you heard of alternating current?

In AC the electrons move in one direction and then the other, thus don't really get transported anywhere...

 

[PlasmaBomb]

Originally posted by: GodlessAstronomer

Originally posted by: So

Originally posted by: SunnyD
I'm curious, because there have been rather few "high-tech" improvements to the way we harness and use energy over the years. How efficient is electron transport compared to other methods? And better yet, will we (humans) ever be able to harness raw energy rather than have to convert it into some more (currently) usable form like electricity? Are there any current advancements underway in this field?

Off the top of my head, the only alternative methods we have for harnessing energy almost all equate with turning them into electricity, almost all through a mechanical means - meaning there's got to be a lot of loss going across the energy production for that method. The only one I can think of that isn't a mechanical device would be photo-electrical generation (solar panels).

As far as alternative energy usage, about the only thing that comes to mind is steam or water power, but those have generally fallen by the wayside or adapted to accommodate mechanical-electrical production (turbines). Even nuclear reactors - capable of giving off so much raw energy - still convert it into a mechanical form which is then turned into electricity.

I'd be curious to see if mankind ever manages to move away from "electricity" as the predominant form of energy. I'm also curious to know how much energy is lost in the various methods we have to generate electricity today.

Okay, you desperately need a physics class before you think any more about this. Your working definition of energy seems to have more to do with a new-agey touchy-feely concept of energy rather than the real world physical concept of energy -- the ability to do work.

That's not at all how I interpreted the OP, not sure where you're getting that from.

WTH is raw energy?

 

[SunnyD]

Originally posted by: So
...Snip...

I'll cut to the chase in the hopes that you do as well oh resident expert.

Answer the original question then. HOW efficient is... say... the energy output of a nuclear reactor from the raw form(s) that it produces and the form(s) which are directly utilized in powering the turbine which produces said electricity?

How much potential energy is lost from the core material that is never recovered in terms of ALL possible forms of energy output, particularly the forms which we don't/can't utilize with current technology?

Finally, I'd be interested in finding out exactly how much of the electrical output from the turbine actually is utilized in terms of efficiency across the grid that it serves.

I know there's several questions there, so go ahead and do your best, and feel free to be technical - no need to dumb it down unless you really want to.

 

[SunnyD]

Originally posted by: PlasmaBomb
WTH is raw energy?

The actual carrier of the potential energy (eg: photon, radiation, heat, etc).

 

[bobsmith1492]

Electric motors can reach ~97% efficiency (DC brushless polyphase). Transmission lines are in the mid-90% efficiencies depending on the distance, of course. Power generation plants can reach almost 50% efficiency (see the supercritical section of the wiki: http://en.wikipedia.org/wiki/Fossil_fuel_power_plant ).

One way for power generation to be more efficient is to use the waste heat to heat buildings or do other useful work. For example, here in Grand Rapids, MI the incinerator produces electricity and the excess steam is piped throughout the city to heat the main downtown buildings. However, this isn't practical for most places; people don't want to live around a nuclear reactor to stay warm, lots of people in the US use AC more than heat, and most people heat with natural gas, anyway (here in MI). In that case, energy is transported chemically as gas.

Superconducting power lines reach extremely high efficiencies, theoretically 100%. Cooling the lines requires some energy, though, preventing the 100% mark.

Coal and oil are transported on ships. The efficiency would be calculated by dividing the energy used to maneuver the ship to its destination by the amount of energy contained in its cargo. That method has its place but is limited to bulk transport of raw chemical goods. Similarly, energy in gasoline is transported all over the place before being used in your car.

The sun obviously transmits massive amounts of energy to the earth; it's not terrible efficient however, considering the raw bulk of energy leaving the sun and the tiny shadow cast by the earth. The primary receptor on the earth is chlorophyll in plants, creating hydrocarbons to store energy - chemical storage leading to wood, gas, and coal.

In conclusion, off the top of my head, electrical and chemical are the most useful methods of transporting energy that are available to humans at this time.

 

[Chiropteran]

Originally posted by: PlasmaBomb

Originally posted by: SunnyD
Alright, I'll give you the confusing terminology - but electrical current is essentially the transport of electrons across a medium (in most cases - though it can potentially be any charged particle, but most often electrons).

Have you heard of alternating current?

In AC the electrons move in one direction and then the other, thus don't really get transported anywhere...

What if you use up all the electrons in a particular wire, then AC power wouldn't work anymore with it because the electrons would be going back and forth without reaching the end of the wire. But if we were using DC, the stream of electrons would fill the wire back up so there just be a short lag until the electricity came out the other end.

 

[bobsmith1492]

Originally posted by: Chiropteran

Originally posted by: PlasmaBomb

Originally posted by: SunnyD
Alright, I'll give you the confusing terminology - but electrical current is essentially the transport of electrons across a medium (in most cases - though it can potentially be any charged particle, but most often electrons).

Have you heard of alternating current?

In AC the electrons move in one direction and then the other, thus don't really get transported anywhere...

What if you use up all the electrons in a particular wire, then AC power wouldn't work anymore with it because the electrons would be going back and forth without reaching the end of the wire. But if we were using DC, the stream of electrons would fill the wire back up so there just be aa short lag until the electricity came out the other end.

Nuh-uh, it doesn't work that way. First, you can't think of it as a number of electrons; it's more like an electric field that pushes the electrons back and forth. Also, DC is actually worse for the wire because of electromigration. If the current constantly flows in one direction, it tends to "push" the molecules of the wire along with the flow of current. It eventually leads to gaps in the wire and thinning sections of wire.

 

[So]

Originally posted by: SunnyD

Originally posted by: So
...Snip...

I'll cut to the chase in the hopes that you do as well oh resident expert.

Answer the original question then. HOW efficient is... say... the energy output of a nuclear reactor from the raw form(s) that it produces and the form(s) which are directly utilized in powering the turbine which produces said electricity?

How much potential energy is lost from the core material that is never recovered in terms of ALL possible forms of energy output, particularly the forms which we don't/can't utilize with current technology?

Finally, I'd be interested in finding out exactly how much of the electrical output from the turbine actually is utilized in terms of efficiency across the grid that it serves.

I know there's several questions there, so go ahead and do your best, and feel free to be technical - no need to dumb it down unless you really want to.

Please, please read the article on carnot efficiency I linked. A nuclear fuel bundle produces heat. That heat has to be converted to work (power) by some process. With nuclear reactors, the only known process that can produce significant amounts of power is a steam turbine, driven by the rankine cycle. The efficiency of that process is limited by the carnot efficiency. This all depends on the design of the turbine, and if it's a pressurized water reactor, the heat exchanger. I'm an electrical engineer, so my thermo days are long past me, but no matter how many efficiency improvements you do, ANY process that converts heat into energy is limited by the carnot efficiency. I really don't feel like doing the calcs to get you concrete numbers, and I'm betting that PWR / BWR reactor heat rates are at least corporate secrets. Basically, we're already doing well for generators (see http://en.wikipedia.org/wiki/Combined_cycle) -- this article says as much as 85% efficient, which given that this: (http://en.wikipedia.org/wiki/C...versible_heat_engines) gives us an ideal equation, which will yield an ideal efficiency of 85.3%, (with a Tc of 852.15k and a Th of 1172.15k) so we're pretty darn close to the best possible.