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Creating Power From Wasted Heat

Zonk posted more than 7 years ago | from the that's-borg-technology dept.

Power 186

Roland Piquepaille writes "Today, about 90 percent of the world's electricity is created through an indirect and inefficient conversion of heat. It is estimated that two thirds of the heat used by thermoelectric converters are wasted and released. But now, researchers from the University of California at Berkeley have found a new way to convert this wasted heat into electricity by trapping organic molecules between metal nanoparticles. So far, this method of creating electricity creation is in its very early stage, but if it can scale up to mass production it may lead to a new and inexpensive source of energy."

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New source of power ? (5, Insightful)

Anonymous Coward | more than 7 years ago | (#18055908)

How is this "a new source of power" ? it's just improving efficiency by reducing loss.

Re:New source of power ? (3, Insightful)

Chmcginn (201645) | more than 7 years ago | (#18056006)

But the result would be the same as doubling the number of power plants available, once this technology (supposing it works as advertised) is installed - you'd suddenly be able to halve the number of running generators.

Re:New source of power ? (2, Insightful)

Fordiman (689627) | more than 7 years ago | (#18056092)

That's if, and only if, the efficiency gain is 100% over nominal. They don't say it is.

Re:New source of power ? (2, Informative)

hack slash (1064002) | more than 7 years ago | (#18056096)

It's a nice idea but the power hungry devices of today are just getting more and more power hungry so doubling the output of a standard power plant will just serve to keep the new power hungry devices running.

Just look at at this previous SlashDot article: http://hardware.slashdot.org/article.pl?sid=07/02/ 16/196235 [slashdot.org]

I wouldn't worry about the computers.... (4, Insightful)

Chmcginn (201645) | more than 7 years ago | (#18056360)

Computers still are, and probably always will be, a fairly small fraction of electrical consumption. Yeah, data centers are all the way up to 1%... But 1% is 1%. Not a big component... Hell, I'd be more concerned about this [slashdot.org] - if we replace fossil fuel cars with electric in the next fifty years, electric power used to recharge vehicles will probably become one of the biggest fractions of the total load.

Re:I wouldn't worry about the computers.... (1)

TapeCutter (624760) | more than 7 years ago | (#18057120)

Also it's takes more a LOT more energy to deliver all that spam as snail mail.

Re:New source of power ? (1)

soft_guy (534437) | more than 7 years ago | (#18057052)

Most devices are becoming more energy efficient. Even for what you are talking about (servers), the amount of energy used per unit of work isn't going up.

Re:New source of power ? (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18056770)

God, you're such a loozer. You must have been the result of a blow job gon bad! Good Lord!

Re:New source of power ? (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18056936)

God, you're such a loozer. You must have been the result of a blow job gon bad! Good Lord!

Hmmm, if I'm getting a blowjob and it turns into me shooting my load into her vagina, instead, I consider that a blowjob gone good. The pregnancy would be sex gone bad.

Re:New source of power ? (4, Interesting)

Fordiman (689627) | more than 7 years ago | (#18056030)

You're exactly right. But the common man doesn't understand 'efficiency gains' as something significant. Perceptually, people don't get how much energy is lost to waste heat.

I mean, hell. If this works well, it could be used as a component in hybrid vehicles; they only have 25% efficiency on the gasoline engine, and if they're parallel types, the heat generated by the gasoline engine could be used to keep the electrical engine in juice.

It might even be possible to recapture a bit of energy off the moderate heat generated in the electrical motor.

Of course, there will be the thermodynamical morons in here, trying to say that this little device is next in the step towards the latest self-powering promise, drawing energy from the zero point or whatever other perpetual motion bollocks is being flouted these days.

Here's a hint guys: you can't win and you can't break even. You can only take your income (solar energy) and savings (batteries, fuels, and nuclear fuels) and spend it (burning fuel or running electrical equipment). If you can boost your output per unit input, great stuff - but please don't assume it means you've hit a lotto (perpetual motion) that doesn't exist.

Re:New source of power ? (4, Funny)

0racle (667029) | more than 7 years ago | (#18056078)

Dude, this is like the next step to a self powering device. It would run forever.

Obligatory (1)

geobeck (924637) | more than 7 years ago | (#18056896)

"Lisa, in this house we obey the laws of thermodynamics!"

New source of power ?-Beans! (0)

Anonymous Coward | more than 7 years ago | (#18056384)

"You're exactly right. But the common man doesn't understand 'efficiency gains' as something significant. Perceptually, people don't get how much energy is lost to waste heat."

Of course we do. Every time someone farts, that's energy lost.

Re:The point of the robot... (4, Insightful)

Oligonicella (659917) | more than 7 years ago | (#18056906)

"But the common man doesn't understand 'efficiency gains' as something significant."

Yeah, they insulate their houses to save on energy bills just 'cause.

Re:The point of the robot... (2, Insightful)

amRadioHed (463061) | more than 7 years ago | (#18057482)

I think he means there is a difference between understanding it's a waste when the heat you are paying for is going out the window, there is a very direct cost. It's less likely for people to think that the heat coming out of the back of their vacuum cleaner is also wasted energy. Electrical appliances get hot when they run, right? Nothing unusual about that.

Re:New source of power ? (2, Interesting)

pudro (983817) | more than 7 years ago | (#18057236)

Nine times out of ten, the "thermodynamical morons" are the ones shouting down the proponents of the "free" power source. The claims are not about whether perpetual motion is possible (it isn't), but whether or not we can get out more energy than we put in by tapping other power sources (anything from naturally occurring temperature differences to some sort of unknown cosmic energy).

The people who always bring up the impossibility of perpetual motion lose the argument before it even begins, since they fail to realize that it is not a closed system (and therefore not a claim of perpetual motion). But they yell louder than anyone else, so the general populace goes on believing that the Earth is the center of the solar system.

Re:New source of power ? (1)

Beryllium Sphere(tm) (193358) | more than 7 years ago | (#18057926)

>hybrid vehicles; they only have 25% efficiency on the gasoline engine,

Toyota claims 45% for the Prius. I don't believe them, but one of the advantages of a hybrid is that it can keep the gas engine in the most efficient part of its working range. On top of that the availability of low-end torque from the electric system frees designers to use low-torque designs like the Atkinson (or Miller) cycle which are more efficient.

Re:New source of power ? (2, Insightful)

jbengt (874751) | more than 7 years ago | (#18056948)

It's not a more efficient thermal cycle or a more efficient dynamo. It is a new source of power - waste heat. OK, waste heat has been used before, usually for direct heating, but not for this kind of electricity production in utility power plants.

Open that fridge! (4, Funny)

cat_jesus (525334) | more than 7 years ago | (#18055930)

So now instead of yelling at my kids for leaving the fridge door open I'll have to get them to leave it open every now and then in order to keep the electricity bill down.

I could really dig have a lower electricty bill in the summer rather than a higher one. When can I build a house with this stuff?

Re:Open that fridge! (4, Funny)

Wavicle (181176) | more than 7 years ago | (#18055982)

In this house, we obey the laws of thermodynamics!

Re:Open that fridge! (0, Redundant)

Fordiman (689627) | more than 7 years ago | (#18056048)

*blinks*

You have to be joking right? A joke that seemed funny at the time? Please tell me this isn't even a vaguely serious idea.

Re:Open that fridge! (0, Flamebait)

Alien Being (18488) | more than 7 years ago | (#18056444)

"Please tell me this isn't even a vaguely serious idea."

This isn't even a vaguely serious idea...

you dumb f*ck.

Re:Open that fridge! (1)

misleb (129952) | more than 7 years ago | (#18057858)

Hey, maybe you can use the head differential between the air conditioned inside and the out outdoors to generate eletricity!

Seriously though, I wonder what the limits are to this. Like, could you use this on solar panels (behind the solar cells) to suppliment the normal solar electricity generation? The cells only convert, what, 5% of the light to electricity. I'm sure the panels get hot. Hot enough to drive this new tech?

-matthew

What? (2)

Meor (711208) | more than 7 years ago | (#18055952)

Organic particles between nano metals? How about a Stirling engine invented 200 years ago?

Re:What? (1)

Teresita (982888) | more than 7 years ago | (#18055994)

Wow, for centuries inventors of perpetual Carnot Engines have been stymied by the same problem: waste heat. Now all you need is a hand wave, some Insta-Nano, and voila! And any secondary waste heat generated by the nano is just that much more fuel. Better sell your petroleum stocks now.

Re:What? (0)

Anonymous Coward | more than 7 years ago | (#18056130)

Well, somewhere in TFA, they speak about temperature differences. But I think you're damn right here, I do not see any reason why this could be any more efficient than a regular steam turbine, which is limited only by the temperature difference of the two heat reservoirs (and only the higher temperature reservoir can be technically changed by burning the coal at higher temperatures).

Daisy-chaining more of these magic nano-thermocouples together would look a lot like trying to create Maxwell's Daemon...

Re:What? (3, Interesting)

anagama (611277) | more than 7 years ago | (#18056208)

It's pretty easy to generate electricity from heat. I have a pottery kiln and one method of monitoring temperature is to use a thermocouple hooked up to a "pyrometer". A thermocouple is just two different kinds of metals connected. Somehow, when you apply heat, a voltage develops (I won't pretend to understand how). Now, I'm a cheapskate and because a pyrometer is nothing but voltmeter scaled for temperature, I just use a couple digital multimeters to monitor kiln temps (in the type of firing I do, the measured temperature isn't really relevant -- I'm more concerned with whether the temperature is rising or falling). I typically get 35 - 40 millivolts at my peak temperature (somewhere in excess of 2400 degrees F if I'm doing things right). The cheapo type-K thermocouples I use lose their accuracy as I approach peak temps, but no way am I spending over $200 each for platinum thermocouples.

Anyway, my point, after reading TFA, it became pretty obvious that this stuff would work like a thermocouple, but you could fit many of them over a large area. It's isn't so much "nano-magic", as it would be a miniaturization of an idea that sees daily application. It sure would be cool if they get it functional.

Re:What? (2, Interesting)

fabs64 (657132) | more than 7 years ago | (#18056810)

Also, from what I read this technology still functions at very low differentials, ie 30 degrees celsius, as opposed to the hundreds that just using two metals requires.

Um (1, Insightful)

Anonymous Coward | more than 7 years ago | (#18055992)

From TFA:

For each degree Celsius of difference, the researchers measured 8.7 microvolts of electricity for benzenedithiol, 12.9 microvolts for dibezenedithiol, and 14.2 microvolts for tribenzenedithiol. The maximum temperature differential tested was 30 degrees Celsius (54 degrees Fahrenheit).
According to my handy-dandy calculator, that's... 0.426 volts, which isn't much. Am I missing something here? Or are they planning on just massively, massively scaling it up?

Re:Um (2, Insightful)

Fordiman (689627) | more than 7 years ago | (#18056072)

Well, there's no mention of current per unit (each, mol, dozen, etc) of each organic oreo, so the voltages are essentially meaningless.

Re:Um (1)

Vario (120611) | more than 7 years ago | (#18056168)

Why should this be a problem? Even with low voltages a lot of power could be saved, just use a large number of these nanoparticles in parallel and you have a nice source for electrical energy. Connecting them together to get an even higher voltage might be possible as, but is not absolutely neccessary, just think of your average battery which operates around 1.5V. Just think of your physics class: power = voltage * current, so a low voltage does not restrict the power output, although it increases electrical losses.

The only problem so far is the low efficency with energy conversion through the seebeck effect and this might be a step into the right direction.

Awful summaries (0, Offtopic)

noidentity (188756) | more than 7 years ago | (#18056000)

"But now, researchers from the University of California at Berkeley have found a new way to convert this wasted heat into electricity [...]. So far, this method of creating electricity creation is in its very early stage, but if it can scale up to mass production it may lead to a new and inexpensive source of energy."

In other words, the "but now" is unwarranted, since there's still waste heat and no practical way to harness it. Until then, it's just "Researchers are attempting a practical way to waste less heat."

I haven't even touched on the excessive use of "but", "could", "may", etc. in recent summaries.

Small scale (1)

hack slash (1064002) | more than 7 years ago | (#18056042)

The Urban Mover company I pre-ordered an electric bike from are working on a hydrogen fuel cell that converts heat to electricity initially for their scooters but will probably see cars being powered too.

Anything in the electricity generation area that improves upon previous methods of squeezing as much power out of your fuel souce can only be a Good Thing[tm].

generation vs consumption (3, Insightful)

mrcdeckard (810717) | more than 7 years ago | (#18056054)

we've seen a lot of "new energy" stories on /. today, and there's been a lot of talk in the media lately, too. but NO ONE is talking about conserving energy. of course, this is an american perspective, and self-constraint is unamerican as it gets.

who cares if we figure out, say, how to meet 10% of our energy needs with new tech when our consumption rises 10% (or more).

a lot of "new energy" isn't really energy. as others have pointed out, hydrogen, is really just a way to transport energy.

it occurred to me recently, that, collectively, humans are like any other organism. we cannot control ourselves from the inside (something to do with goedels theorem maybe), and thus we will overrun the planet until we choke on ourselves -- or run out of energy. so i don't worry about it too much.

oh. whoops. depressing cold day here in st louis today.

mr c

Re:generation vs consumption (1)

Fordiman (689627) | more than 7 years ago | (#18056162)

You're right, of course. Conservation in the home is step one. Of course, conservation in the production industry is another very good step.

Why not conserve that additional 10%?

Low powered CPU cores, higher efficiency appliances, LED light bulbs, and similar efficiency improvements could see that personal conservation isn't needed for several years.

I dunno. Are you one of the sorts who oppose things like thorium-based reactors for political reasons rather than on their merits?

Re:generation vs consumption (5, Insightful)

Doppler00 (534739) | more than 7 years ago | (#18056610)

LED light bulbs are overrated. Compact florescent bulbs are much more efficient, but they aren't a sexy as LED's. Here's some ways to conserve, but no one will do this:

1. No more incandescent bulbs.
2. Live 10 minutes away from work in a condo/apartment instead of the suburbs in a giant house
3. Stop leaving your computer on all day

Actually, #2 is about the only one that really saves the most money. Smaller places cost less to heat/cool, and not driving as much saves a huge amount of energy.

But, oh environmentalists are more concerned about prohibiting housing developments or zoning that actually makes sense.

Environmentalists? (3, Interesting)

wytcld (179112) | more than 7 years ago | (#18057326)

What's your sample to say what "oh environmentalists" are concerned with? Consider Portland, OR, where environmentalists put in zoning to pack housing into the center of town and prohibit it from sprawling farther out. (True, the anti-environmentalists lately threw a wrench into that with a misleading statewide referendum.) Or on the other side of the country, environmentalists in Vermont are also encouraging more housing in and close to traditional town centers rather than sprawling across the countryside. What is your sample set of "environmentalists" who prefer that we'd all live in suburbs in giant houses? I'd suggest that whoever you can find fitting that description just flies a flag of convenience - the evil often cloak themselves in the names of the good.

more on condo vs. house (1)

SpectralDesign (921309) | more than 7 years ago | (#18057554)

Adding to your point #2:

Smaller place - less to heat/cool (and furthermore, typically you have only 1-3 exterior "walls" vs. a minimum of 5 for a house, meaning that your radiant environmental stabilization is being re-cycled by your neighbors in a condo or apartment, and being completely wasted in a house).

Not driving as far (and typically, better access to mass transit.. less energy to get to/from work, school, shopping, etc.)

Also, when trash pickup is done for your apartment there's one truck that takes 2 minutes to get the weeks trash (and recycling) from hundreds of families -- unless you live in a house and that costs hundreds of times as much energy per family.

For those that don't give a hoot about these "environmental" reasons to live in a smart space there are other advantages to an apartment in the city vs. a house in the burbs:

more time for yourself -- less time stressing out in traffic jams.

you don't need to mow the lawn, water the flower beds, rake the leaves, or shovel the snow.

you might actually get to know some of your neighbors.

I'd like to see what others can add (or detract) to/from this post!

Re:generation vs consumption (-1, Flamebait)

GigsVT (208848) | more than 7 years ago | (#18056258)

overrun the planet until we choke on ourselves -- or run out of energy

That won't happen. These things are self regulating, because we don't live under socialism. If energy becomes scarce, the price will go up and consumption will go down. Socialism and excessive government interference with the free market is the only credible threat to the environment.

Re:generation vs consumption (0)

Anonymous Coward | more than 7 years ago | (#18056354)

Socialism and excessive government interference with the free market is the only credible threat to the environment.

Bull shit. So humans cannot damage the environment without socialism and/or "government interference"?

How about laws to protect the environment?? Ever heard of the tragedy of the commons?

Hell of a lot of species went extinct or nearly are extinct *because* of no interference from government. Governments are the ones that should be working all the time to prevent tragedy of the commons. This includes such important items like food, water, air and maintaining a bio-diversity. "Free market" is completely useless without rules. Hell, why would one need cattle ranchers or anything like that? Kill some elephants, whales and whatever else is big enough. Cheaper!! That's free market! See bison in North America. Or whales. Or freaking fish in the oceans. Or the Great Lakes in North America and their pollution. Or why there is no wild animals larger than a cat anywhere but Africa (or, a bit exaggerated, but all of the species larger than a cat other than Africa are on some sort of endangered list)

Socialism is actually better at protecting the commons IFF the policies are sane and geared towards protecting the commons. Why is it better? Because the primary goal of the society is not money, it is to follow the rules. In a capitalist society, one wages the rule following with profit. If one can make $5mil for dumping some crap in the river or air, well, are potentially 3 months in jail worth it? Maybe. Maybe not.

Anyway, socialism in practice has nothing to do with environment. Ditto for capitalism. IF you think otherwise, you are a fucking moron.

And governments (capitalist or communist or whatever) *should* be protecting the commons by regulations, but are not. That's the problem. That's the treat to the environment - lack of regulation of the free market (or any other economy). Environment *must* be put first, or everywhere all we'll see a humans and more humans and no tree, just smog.

Just look at China or almost bloody any country in the south-east Asia, especially during summer. Fucking smog everywhere. So thick you can cut it with a knife. And what do people complain about? Traffic jams, corruption, money. FUCKING **MORONS**.

The market didn't do a thing to help stop... (3, Insightful)

zogger (617870) | more than 7 years ago | (#18056748)

...water pollution. Nothing. Zero. It took serious government regulations in a lot of directions at the federal, state and local level and mass civil indignation to do that, because the "market" ALL found it cheaper-better for their "shareholder value and bottom line"- to just dump their toxic waste wherever they felt like it and to transfer health care costs to -anyplace else, downstream usually.

  Ya, maybe if we had waited say a few hundred years it might have "corrected", as the remaining few non mutants rose up finally and bumped off the remaining few mass polluters who were left, but for some reason society decided to step in with some stricter laws before it got that bad.

I could name numerous other examples but that is an easily seen one.

Sometimes you just can't wait for the "this quarter's profits" mentality boys to do the right thing. Some things might need to be addressed now, once they are clearly understood to either be a problem now or soon will be, as opposed to waiting around for a long time in an economic and social experiment to see what might happen. And believe it or nuts, there are more important things on this Earth than some corporation's bank balance.

That is not to say that government can't be hugely overbearing and infested with generic mass stoopidity itself,of course it is,I speak out about government abuses all the time, but "the market" is no better really, neither extreme -leave it all to the market (caveat-emptor brand corporatism would be the extreme there) or all to the government(cult of the personality one leader-one party-mass bureaucracy and no one even wants to work any longer except under the whip"- ism government would be the extreme that other way)- is the end all or be all of "solutions". I think what we have more or less constructed- at least semi-regulated markets and at least an attempt at a semi-regulated society via this government thing-is probably the best humans can do at our (barely out of the medieval level intellectually or psychologically) evolutionary stage.

Of the two extremes and the middle, the middle is what we mostly have and falls under the lesser of the three big evils choices. It is imperfect, absolutely no doubt there, but the best we can do right now. What we can do is to keep chipping away at the imperfections on a case by case basis.

Re:The market didn't do a thing to help stop... (1)

GigsVT (208848) | more than 7 years ago | (#18056820)

...water pollution. Nothing. Zero. It took serious government regulations

No one owns waterways. It's a problem created by socialist public ownership of waterways. You can't revoke private ownership of something then point to the failure as a failure of the market, socialism created the problem.

I could name numerous other examples

Well you better try again. Government regulation to control a problem created by socialism isn't a good example for your argument.

(barely out of the medieval level intellectually or psychologically) evolutionary stage.

Speak for yourself. Liberals somehow have the dual belief that humans are stupid, yet somehow capable of being bestowed unlimited power to commit violent crime without repercussion (the government) without becoming corrupt. Which is it?

Of the two extremes and the middle, the middle is what we mostly have

It's a false dichotomy. You have created a straw man choice between socialism and regulation to control problems created by a lesser amount of socialism.

Re:The market didn't do a thing to help stop... (1)

Rakishi (759894) | more than 7 years ago | (#18057256)

Ah but what is your solution then? Since private ownership of things like water and air isn't exactly feasible what do you propose? All these problems we talk about are those impacting areas whose ownership cannot be restricted by their very nature (air and water flows around).

So yes his comparison is perfectly justified, for the problems in question you yourself seem to admit no capitalistic solution by your failure to actually challenge his point.

Re:The market didn't do a thing to help stop... (1)

TapeCutter (624760) | more than 7 years ago | (#18057460)

"Government regulation to control a problem created by socialism isn't a good example for your argument"

By that measure all goverment "for the people" is socialism, perhaps the stigma attached to socialisim is why goverment "for the people" is so uncommon these days.

If we accept the idea that rivers are "private" then someone polluting a private river still pollutes everyone else's "property" who lives downstream leaving you in the same position of having to impose government regulation to stop someone else polluting YOUR river. Or were you thinking that one corporation should buy an entire river, say Montanto purchasing the Mississipi, even if that happened it would be a different story with the Danube.

The idea that "socialisim caused the problem" is nothing more than dogma. It doesn't matter if rivers are public or private property, the problem of pollution is caused be "the people" or "the person" not respecting said property and thus degrades everyone else's property. Eg: I don't have a river on my property so if I dump paint thinner down the public stormwater drain it's someone else's problem, right?

Government regulation to stop pollution is in fact "the people" taking ownership of their property.

nuts (1)

zogger (617870) | more than 7 years ago | (#18057856)

I can't say much about your drivel other than you are rather bonkers. No, "socialism" didn't make General Chemical and Sludge dump toxic waste into the drinking water supply, GREED and being jerks did.

    As to being a liberal, I am what is now called a "paleocon", a normal plain vanilla regular old timey Constitutionalist, and as such, I recognize the need for SOME government, because we need it. Not overbearing and bloated. I mean I started my political activism working both normal conservation issues AND on the GOLDWATER campaign. Notice root word, conservative-conserve-be a good steward. I see nothing contradictatory there. Now I did pull one year as a dues paying capital L, but left because of similar bonker theories I kept hearing about total private ownership of everything, laws be damned, etc. Nuts. they won't work in the real world because corruption-which you pointed out-is there. In government we at least have a slim chance to get the bums out, with entrenched corporations whcih invariably fall into cartels and monopolies-you can't get rid of them! Freaking vampires! And their track record? Dismal. We are forced into a lesser of evils stance, some government, some market, case by case basis following our old simple laws works the best.

No, I don't want your corporation owning all the water, no thank you, nor the air,no thank you. They failed it, proof is in the pudding, they had their chance and blew it bigtime, and even today, even with regulations they are still pretty sleazy about it to save a buck for themselves.. And I sincerely doubt most other people would think your switch to corporations owning everything and "leaving it up to the market" is a good idea either. We dumped "snakeoil" as a concept, because that is what happened, mass snakeoil from "the market". And that's not a strawman, that's as direct as it can be put. No, I reject your corporatist company store model total private ownership of every single possible thing theories. Some things, not everything, but some important things, are better left to the commons, and to be protected by the commons. Our founders thought so as well, that is one of the main reasons for having a government in the first place! The major rivers, etc, "owned" by the people in the states they went through, not by ACME Rivers inc., equaly shared out to the middle for the people, for general usages, and we finally realized as a society that because of asshat corporate water polluters, to use my exact point again which fits perfectly as an example, the jerks who just refused to stop, so we needed to slap some regs on them, because..well..they were asshats about it, they screwed up royally when left to "market forces", because in a lot of cases "market forces" just won't work, that is just proven past data back from when we didn't have regulations about such things, they all just dumped crap willy nilly, and it caused *problems* that "the market" wasn't addressing.

    For some things they do,markets work just fine and no one cares if you make a buck, that's the deal we all work under, for others they don't, we need a little common government action, and it is as simple as that.

Re:generation vs consumption (1)

FormulaTroll (983794) | more than 7 years ago | (#18056962)

Socialism and excessive government interference with the free market is the only credible threat to the environment.
Because the true goal of capitalism is responsible stewardship of resources for the greater good of all!

Re:generation vs consumption (1)

rolfwind (528248) | more than 7 years ago | (#18056756)

a lot of "new energy" isn't really energy. as others have pointed out, hydrogen, is really just a way to transport energy.


So is oil, when you get down to it.

Doesn't make hydrogen any more or less viable.

Re:generation vs consumption (1)

mrcdeckard (810717) | more than 7 years ago | (#18056908)

yes, absolutely. oil is the closest thing to free energy we have on this earth -- but only because it is the suns' energy stored up from bazillions or years. of course, we're seeing that it's not really free with the environmental problems, but that's besides the point. a gallon of oil contains quite a bit of energy, not to say all the stuff that can be made from it.

but hydrogen is not energy. we still need the energy to prepare the hydrogen for consumption. biodiesel is not free energy. the consequences of farming the amount of land to grow the crops to generate the biodiesel will have negative environmental effects (supposedly this is happening in mexico with corn flour being used for ethanol). wind power, hydroplants, and solar power are a good sources, but how much energy can we really generate with these methods, and, what large scale impacts will they have on the environment? (for example, if we covered a coast with wind turbines, how would that slow down the wind -- how would that affect the weather inland?)

as i understand it, nuclear is really the closest thing we have to free energy. the only risk, as i understand, are meltdown (cherynobl) and what to do with the waste. (in hindsight) cherynobl was of a design that should've never been built in the first place. i think that we could feasibly engineer a solution to the waste problem -- not ideal, but a lot better than the course we're on now -- energy and environmental crisis.

and i'm burning it up at a pretty good clip. i have a small, drafty flat in saint louis, where it's pretty cold this week, and my super old inefficient furnace is running quite a bit burning off fuel. i've been burning about 10 gallons of gas in my old car with a slipping transmission driving around to school, because it's too cold to ride my motorcycle, and saint louis is notorious (as a lot of american cities) for its bad public transit.

i plan on buying a house, and the first order of business is to insulate the hell out of it. not the best thing aesthetically (saint louis buildings are beautiful when you expose the interior brick, but very efficient -- at conducting heat that is). even if we don't run out of energy, the price is going to go up and up and up.

it will be the failure of our species that we blindly burned it all off, and let a few people decide our energy policy for their own profit (i at least hope they're profiting, otherwise they're just dumb). oh, sorry. depressing cold day again.

it's getting better, tho. my girl brought home some 1/2 off valentines chocolate. mmmmm, chocolate.

mr c

Re:generation vs consumption (1)

babyrat (314371) | more than 7 years ago | (#18057012)

Depending upon what you believe, there is no new energy. The big bang released all the energy there is and ever would be.

who cares if we figure out, say, how to meet 10% of our energy needs with new tech when our consumption rises 10% (or more).

It a heck of a lot better than having our consumption rise and not having a better way to deal with it...

Who cares if we find a cure for cancer when people are just going to die in car accidents?

Re:generation vs consumption (1)

mrcdeckard (810717) | more than 7 years ago | (#18057110)

Who cares if we find a cure for cancer when people are just going to die in car accidents?
that's a good point, but it misses mine, which is closer to:
"who cares if we find a cure for lung cancer if people smoke more and more cigarettes?"

of course i am for more efficient uses of energy, etc. but i don't think we're *addressing* the real crisis: our reckless use of our resources. also, i put forth a crude theory that, as a species, we're *unable* to effectively do so.

how many people here would, if they were a CEO or politician, would get up in front of the public or board members and say, "if we tighten our belts, and accept cut backs in our way of life, accept smaller profits, we can get our society back on track for a brighter, sustainable future."?

if you answered no, you're pretty much everybody. if you answered yes, then you'd be out of a job P.D.Q.

mr c

Not by trapping molecules actually... (4, Informative)

drerwk (695572) | more than 7 years ago | (#18056058)

The post is misleading. FTFA

The researchers coated two gold electrodes with molecules of benzenedithiol, dibezenedithiol or tribenzenedithiol, then heated one side to create a temperature differential. For each degree Celsius of difference, the researchers measured 8.7 microvolts of electricity for benzenedithiol, 12.9 microvolts for dibezenedithiol, and 14.2 microvolts for tribenzenedithiol. The maximum temperature differential tested was 30 degrees Celsius (54 degrees Fahrenheit).
So the device is a thermocouple. You give is a temperature difference and it generates a small voltage. Notice that the current generated is not mentioned, so we can not even tell how much power is generated. If there is something new here it is that we have an organic Seebeck junction instead of the typical solid state junction. The article mentions your car's radiator as an example of wasted heat - no doubt - but to use that heat you need to provide, and maintain a heat differential across your 'recapture device'. Likely the device will just act as an insulator, and your radiator will no longer function. If not you will find that you need some huge fan to blow even more air past the radiator, and now the amount of energy you recover is less than that needed to drive your fan. I also think that the 30% efficiency mentioned for electricity generation is a bit on the low side. Don't hold your breath.

Re:Not by trapping molecules actually... (2, Interesting)

TubeSteak (669689) | more than 7 years ago | (#18056486)

. The article mentions your car's radiator as an example of wasted heat - no doubt - but to use that heat you need to provide, and maintain a heat differential across your 'recapture device'. Likely the device will just act as an insulator, and your radiator will no longer function. If not you will find that you need some huge fan to blow even more air past the radiator, and now the amount of energy you recover is less than that needed to drive your fan. I also think that the 30% efficiency mentioned for electricity generation is a bit on the low side. Don't hold your breath.
Why do you have to use the radiator?

How about sticking this thermocouple directly on the engine block/exhaust pipe/other and just add another radiator somewhere else? You know, like what they do for turbochargers or transmissions.

It'd be nice if it helped your main radiator, but is doesn't have to. If you don't assume that, then you don't have to worry about a fan or insulation & the rest of your objections vanish.

But in the end, I'm not sure what you'd do with the extra electricity in a car, unless we're talking electric motors.

Re:Not by trapping molecules actually... (5, Informative)

drerwk (695572) | more than 7 years ago | (#18056598)

Why do you have to use the radiator?
I inferred from the article that one might add these devices to the radiator to recapture lost heat, and that it would be done for cars already in use. But your question is quite valid. The actual reason for a radiator in a car engine that has one, is to keep the temperature of the engine low enough so that the moving parts continue to move, that the oil lubricates, and that parts don't actually melt. If one had materials that could take the heat, say piston liners that were excellent insulators and still allowed the piston to move, and all of the excess heat simple exited the cylinder you would not need a radiator. Or if you owned a Beetle, a 2CV, or some other vehicle with an air cooled engine you would not need a radiator.
But fundamental to thermodynamics is that you can not have a cycle more efficient than the Carnot Cycle http://en.wikipedia.org/wiki/Thermodynamic_cycle [wikipedia.org] . This give a max efficiency = 1-(TEMPlow/TEMPhigh), so you always want that low temp to be as low as possible - for a car engine that would be the ambient air. If you have your device, then the hot side is on the engine, and the low side is in the air. But the device itself will get hot, an you will have to blow a lot of air on the cold side to keep it cold. It you let the whole device rise to the same temperature you get no conversion.

Re:Not by trapping molecules actually... (1)

sanman2 (928866) | more than 7 years ago | (#18056688)

There are engines which use ceramic lubricant that has much higher heat tolerance. This permits the engine to run at much higher temperature and also greater thermodynamic efficiency.

Re:Not by trapping molecules actually... (0)

Anonymous Coward | more than 7 years ago | (#18057216)

Organic solar cells have a problem of short life time. I wonder if organic Peltier elements will have the same.

Indeed- it's only a smallish breakthrough... (1)

Svartalf (2997) | more than 7 years ago | (#18057718)

I believe I saw what might pass for Zt values given for the stuff in another [greencarcongress.com] article:

benzenedithiol: 8.7 microvolts/K
dibezenedithiol: 12.9 microvolts/K
tribenzenedithiol: 14.2 microvolts/K

To put this in perspective with what we already have in the way of commonly used thermoelectric materials, Bismuth Telluride weighs in at -287 microvolts per degree Kelvin for N-doped material and 87 microvolts per degree Kelvin for P-doped material.

What we're reading about is roughly 1/5th as efficient at doing thermoelectric effects as the most efficient stuff we have for P-doped material at the consumer level- which isn't really all that efficient, but is useful enough if you're needing cooling or thermoelectric generation in tight spaces that wouldn't accomodate other answers. The "wow" comes from it being the Thermoelectric equivalent of an OLED back when OLEDs were still more of a lab curiosity than a sort of fielded part of the time technology.

Brass tacks here: It's NEAT beyond words, but it's not the thing the article made it out to be. It's not even as good as the best we have in Peltier devices yet.

Heh... This is what I get for posting late... (1)

Svartalf (2997) | more than 7 years ago | (#18057726)

Read: ZT == Seebeck Coefficients...

Needs must have SOME sleep before posting- but then, this IS Slashdot, right? >:-)

Just ignore the post... (1)

Svartalf (2997) | more than 7 years ago | (#18057752)

Heh... I'm so freaking tired and out of it, I didn't even notice that you'd already quoted the values, etc.

Not enough caffene, not enough sleep. Time to go to bed.

2nd Law (2, Interesting)

some_hoser (656003) | more than 7 years ago | (#18056080)

I hope no one here will forget about the 2nd law of thermodynamics...

Re:2nd Law (1)

Harmonious Botch (921977) | more than 7 years ago | (#18056110)

I think Roland P already did.

Re:2nd Law? Try the 3rd law (2, Informative)

Mr Pippin (659094) | more than 7 years ago | (#18056432)

I think the 3rd law is more appropriate here, since they are basically talking about using the waste heat of an earlier process, and converting part of it to usable energy.

The 2nd law just basically states that any energy conversion process cannot be 100% efficient, AKA "entropy".

In effect, this is adding a secondary process to the first (or possibly list of processes), of which we already know some amount of energy will escape due the 2nd law.

This additional process just makes the overall process more efficient, and does not really add to it above the original process's input energy. However, the 3rd law just states you can't achieve 0 entropy in a process with a finite number of steps. Basically, you can never have a process that is 100% energy conversion efficient.

Probably the more important question is does the increase of enthalopy merit the proposed decrease in entropy? AKA, does the cost of implementing this solution outway the benefit.

the Jews are Behind This! (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18056136)

Yet another proof that the Jews are at the heart of the energy crisis! They even put the Star of David right in the diagram!

TEC? (1, Interesting)

Anonymous Coward | more than 7 years ago | (#18056196)

"However, such thermoelectric generators operate at a paltry 7 percent efficiency, compared with the 20 percent efficiency rate for traditional heat engines. Moreover, such converters are made up of exotic, expensive metal alloys, such as bismuth and tellurium, making them too costly and impractical for widespread use."

Its an organic peltier... nifty. Wonder if it works as well as a heat pump.

Awesome! (4, Funny)

nacturation (646836) | more than 7 years ago | (#18056248)

So this means global warming is a good thing. With all the electricity we'll be able to make, it's no problem to just run enough air conditions to solve the problem.
 

Re:Awesome! (1, Insightful)

Anonymous Coward | more than 7 years ago | (#18056336)

"Global Warming" is only a good thing if you are a politician, or a special interest group receiving tons of money for combatting "Global Warming"

Note the use of quotes, indicating a ficticious topic.

Re:Awesome! (1)

Servo (9177) | more than 7 years ago | (#18056414)

Actually, AC units just transfer the heat from one spot to another. You actually add heat to the mix from the electric motors in the units as well, making things even worse for those "outside".

Re:Awesome! (3, Funny)

nacturation (646836) | more than 7 years ago | (#18056648)

Air conditioners also sometimes make a nice "whooooosh!" sound, similar to the one just heard.
 

Kurt's Law (1)

Excelcia (906188) | more than 7 years ago | (#18056296)

I've come up with a new law: The odds of an announcement regarding an "inexpensive source of energy" having a disclaimer that "this method of creating electricicty creation [sic] is in its very early stage" approaches one as the amount of energy in the proposed invention increases, and/or as the cost decreases.

And yet... (2, Interesting)

belg4mit (152620) | more than 7 years ago | (#18056466)

Cogeneration only wastes about 1/3 of the energy. That's not too far off from
the Carnot efficiency of 86% for a combustion temperature of 2000 centigrade.
And even the reamining "waste" heat could be used if better planning happened:
district steam, drying and other industrial uses.

A massive supply of wasted heat (1)

El_Oscuro (1022477) | more than 7 years ago | (#18056476)

Every one of us has something we use daily that generates massive supplies of waste heat - our car engines. Instead of releasing it to the atmosphere with radiators and fans, couldn't we convert some of it to electricity with some sort of small turbine? If we did that, we could use it to help power the car with a hybrid motor. Kind of like regenerative braking, but the energy source is constant. I would love to get that extra heat as torque for my Camaro! Maybe I could get on dragtimes.com [dragtimes.com]

Re:A massive supply of wasted heat (1)

drinkypoo (153816) | more than 7 years ago | (#18056782)

The problem is that the equipment to do this is heavy and bulky. You have to do something with the heat, it doesn't magically generate electricity. Thermocouples are horribly inefficient, for example. And to run a turbine you need steam. Stirling engines aren't usually very efficient, and when they are my understanding is that they are quite large. So we're talking about using the heat to boil water... but the way the car's cooling system is designed, it's only a few to maybe 30 degrees over the ordinary boiling point of water. So there's not all that much temperature differential to work with there, as there is when you put a flame (hundreds to thousands of degrees) to water. And then, if you don't want to be carrying water and throwing it away, you need a condenser for all that steam, which means that you're going to be using a less efficient and thus larger gas to gas heat exchanger (steam to the atmosphere) than the water to air heat exchanger we know as a radiator.

Re:A massive supply of wasted heat (0)

Anonymous Coward | more than 7 years ago | (#18057136)

It's called a small low pressure turbocharger. Most people think that turbo chargers use the pressure of the exaust to spin them, but they actually using most of the waste heat from the engine (thermal expansion causing the pressure in the turbine).

The turbine then spins the compressor, which pressurizes the intake manifold and reduces pumping losses in the engine (and allows for smaller engines with higher power).

So not only do you end up with a more efficient engine, but you get more power as well if you want it.

Way to save energy.. (1)

willy_me (212994) | more than 7 years ago | (#18056480)

Producing electricity from a heat source (gas, coal, nuclear) is wasteful - typically only ~40% efficient. So in order to maximize our use of resources we should make use of that wasted heat. Pumping the heat (via water) to neighboring houses and greenhouses is just one example that is commonly used in Europe.

But this brings up another idea. Why not do away with burning fuels for heat. Large building could instead burn fuels to generate electricity and use the waste heat as their heat source. Extra electricity could be sent to the grid at nearly 95% efficiency. I say 95% efficiency because almost all the the energy released by the burning fuel is put to work.

In warmer climates this approach would be less useful, but it would still be effective for heating water. An entire block of building could get together and share a single generator/hot water heater.

Anyway, this is just a thought resulting from seeing large buildings in cold weather being heated via natural gas while knowing that the electricity powering the building was only 40% efficient.

Willy

Re:Way to save energy.. (0)

Anonymous Coward | more than 7 years ago | (#18056592)

Because there's apparently a huge amount of efficiencies of scale when generating electricity. "Home generators" would waste more than they'd gain in savings.

I say apparently because, while I don't have any numbers at my fingertips, I do know power plants are huge and expensive, which is a big problem for power industry planning that they'd presumably change if they could. And the backup diesel generators many buildings have are horribly inefficient.

It's a nice idea, but I think practically it's a non-starter.

Re:Way to save energy.. (2, Informative)

willy_me (212994) | more than 7 years ago | (#18056900)

They don't have to be efficient. The wasted heat is used in the building so there is effectively no waste. Any electricity generated is just an added bonus.

Large thermoelectric plants are ~40% efficient. A burner heats water, the steam passes over a turbine (connected to a generator), the steam is then condensed (where all the energy is lost) and pumped back into the water tank so it can be heated again.

My suggested idea would, most likely, use an internal combustion engine at ~25% efficiency. But even at a lower efficiency it is still more efficient then just burning gas at 0%. (Note that the efficiency ratings are for electricity production.)

Willy

Re:Way to save energy.. (1)

Rakishi (759894) | more than 7 years ago | (#18057340)

They don't have to be efficient. The wasted heat is used in the building so there is effectively no waste. Any electricity generated is just an added bonus.

That may work in some place, some of the time. In most places that extra heat will have to be vented out somewhere as you don't want your house to be a furnace. Back in NY we shut off the heaters as the small amount of heat coming from the pipes passing by the walls, good insulation, sunlight and our own heat production more than sufficed (I had to open the windows at night in December when I visited). Then you have problems with reliability (thus costs and need for backup heating systems), safety and noise (need to keep that puppy quite).

Note how the countries where such systems exist are the ones that are actually in need of them most of the year, heats not something you want when you're running the AC over half the year.

I'm sure some solar heating would more than suffice for water heating and even house heating in most places. Honestly, if you're going to add something that will do everything you want it to with good reliability then I'd just go add some solar panels and solar water heating then call it a day.

Solar Electricity (0, Offtopic)

RebelSponge (1065066) | more than 7 years ago | (#18056524)

Whatever happened to PV cells? Are we just gonna give up on those becoming a reasonable reality (i.e. not cost prohibitive)? Wait, I got it, lightning bugs! Harness their power!

Imagine (1)

Disharmony2012 (998431) | more than 7 years ago | (#18056608)

a heatsink with the ability to change processor heat into electricity. It could be used to cycle back extra energy into the PSU while cooling itself. Less noise, less electricity. Or having engine walls with this material, to replace the altenator/magneto.

Re:Imagine (1)

Nullav (1053766) | more than 7 years ago | (#18056724)

I concur. It could drastically cut costs of running large-scale server farms if . I really don't see much savings for someone with one or two machines. Although, no one can really say for sure, since we're witnessing round 2 of the MHz wars.

Re:Imagine (1)

skelly33 (891182) | more than 7 years ago | (#18056996)

While we're wishing, how about a decent performing processor that doesn't put out waste heat or require a heat sink? How about a power supply that only draws as much power as is required to run the attached equipment? How about a respectably sized solid state hard drive to replace the millions of spindles running between 5000 and 15000 RPM around the world?

Re:Imagine (1)

Rakishi (759894) | more than 7 years ago | (#18057362)

While we're wishing, how about a decent performing processor that doesn't put out waste heat or require a heat sink?

Get a laptop (or a laptop cpu) or one of those small via things, oh wait you want cutting edge performance AND low heat production.

How about a power supply that only draws as much power as is required to run the attached equipment?

What the fuck DO you think power supplies do, baring some minimal constant loss?

How about a respectably sized solid state hard drive to replace the millions of spindles running between 5000 and 15000 RPM around the world?

Hard drives don't take much to keep spinning.

Re:Imagine (1)

skelly33 (891182) | more than 7 years ago | (#18057668)

"(...) oh wait you want cutting edge performance AND low heat production."

Why yes, I do.

"What the fuck DO you think power supplies do, baring some minimal constant loss?"

Funny you should mention it right after suggesting a laptop. The power supply for my laptop, a transformer with DC rectifier, does not in fact match consumption with load. Neither do the millions of others like it.

How about something a little more constructive next time?

Re:Imagine (1)

Rakishi (759894) | more than 7 years ago | (#18057754)

Why yes, I do.

Then you make no sense, to do that would require lowering what constitutes cutting edge (ie: performances at the cost of everything). If you do that then you may as well just buy a less than cutting edge system and in the end you come out mostly the same. That statement would only make sense if there were no lower power options yet there are, and power consumption is a major problem for chip makers (when its not you get things like the cray).

Neither do the millions of others like it.

Yet again you make no sense, your statement would only be non-idiotic if no such power supplies existed and yet most systems do in fact have such power supplies. So now, you want portability and something else? See above for why that is stupid.

How about something a little more constructive next time?

Well, mostly I'm wondering wtf you're talking about as much of it makes little logical sense. Now if any of it did make some sense I could add constructive comments but as to me it doesn't I can simply point out what is wrong.

Energy from waste heat (1)

pipingguy (566974) | more than 7 years ago | (#18056618)

Isn't that called cogeneration?

Good to see (2)

darklordyoda (899383) | more than 7 years ago | (#18056928)

Good to see that some professors can both do research and teach without lacking in one or the other. Professor Majumdar's a nice guy, his heat transfer class was very well taught, really helped get me interested in heat transfer as something to elaborate on for MechE.

Waste heat density same as solar heat (1)

140Mandak262Jamuna (970587) | more than 7 years ago | (#18056958)

The main problem in recovering energy from a diffused source with a small temperature diff over the surroundings is the little thing called Carnot limit efficiency. If the alleged technology is really succesful there is no need to limit it to waste heat. We could apply it equally well to solar energy collection too. But sadly, looks like the alleged device is a very low efficiency thermocouple.

You know I have been thinking.. (0)

Anonymous Coward | more than 7 years ago | (#18056976)

Since we are so inefficient at converting heat into energy, could this possibly contribute to global warming? If we are using so much heat to convert to energy, how much of that wasted heat just heats the atmosphere instead of making energy?

Wasted Heat..... (1)

IHC Navistar (967161) | more than 7 years ago | (#18056992)

Someone could make a killing if they harnessed all the wasted heat produced by Congress.

Sanitaion might be a problem though, since they all talk out of their asses.

Piquepaille (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18057016)

Go away, please.

Sounds like a job for... (1)

skelly33 (891182) | more than 7 years ago | (#18057038)

...a traditional heat engine like a Stirling Engine. I just trust something I can take a wrench to more than a convoluted biological solution that has biosystem requirements.

If this works (1)

wtansill (576643) | more than 7 years ago | (#18057070)

we can generate power for the entire nation by fitting out the halls of Congress. Finally -- a good use for all that hot air!

Not a big deal (4, Informative)

Solitonic (136324) | more than 7 years ago | (#18057156)

Unfortunately, thermoelectric converters based on the Seebeck effect are not going to help with efficiency by a large amount.

Firstly, there is a theoretical limit (Carnot Cycle [wikipedia.org] ) to the efficiency of any pure heat engine based on the Second Law of Thermodynamics.

If a quantity of heat Q is taken from a high-temperature reservoir at temperature T2, partially converted into useful work W, and the remainder (Q - W) is deposited into a low-temperature reservoir at temperature T1, then the net increase in entropy is at least

      \delta S = (Q-W)/T1 - Q/T2 >= 0.

So the efficiency (useful work generated per unit energy input)

      e = W/Q < (T2 - T1)/T2

The waste heat is ultimately deposited into the environment, so T1 can't be much smaller than say 300K.

In a steam engine T2 has to be greater than the boiling point of water (at whatever pressure it is operated), but it is limited by what the materials of which it is composed can withstand. Temperatures of order 1000K are typical. That gives a maximum theoretical efficiency of around 70%. The best steam engines barely reach about half that efficiency.

However, modern power plants (which are not pure heat engines) use a Combined Cycle [wikipedia.org] that can do better by first generating electricity from their fuel with a combustion turbine and then using the waste heat from the combustion turbine to make steam to generate additional electricity via a steam turbine. Their efficiency can reach about 60% of the net calorific value of the fuel.

So you can see that one might be able to shave a few more percentage points off the waste, but it will not at all be the godsend we really need...

IMHO only nuclear power can fulfill that role today.

Re:Not a big deal (2, Insightful)

Mafiew (620133) | more than 7 years ago | (#18057266)

Thank you for a post that actually talks about some thermodynamic principles. Tapping into "waste" heat does seem like an attractive idea to people who do not have an understanding of thermodynamics. My understanding is that if you try to simply strap on another heat engine like a thermocouple, you're working with a very low temperature differential which means low efficiency.

One question though. Isn't a gas turbine just another heat engine that that is governmed by the limits of any thermodynamic cycle? So would a "combined cycle" be two heat engines connected to each other? Unfortuantely my understanding of thermo is limited to one undergraduate class.

it can solve global warming! (1)

ILuvRamen (1026668) | more than 7 years ago | (#18057276)

well hook a bunch up to air conditioners and global warming will solve itself :P (Yes I DO know that they put off almost as much heat out their output vents as they take out of the air lol)

"Wasted" heat is not available for this device. (5, Informative)

jolathe (1065500) | more than 7 years ago | (#18057288)

The "wasted" heat that thermal power plants reject to the surroundings is rejected at a temperature only slightly above ambient. A steam turbine generator has an exhaust steam condenser which operates at a vacuum, where the steam condenses at only a few degrees Fahrenheit above the ambient temperature. There is no significant temperature difference available for the new device to operate with. While thermal power plants do reject over half the fuel energy consumed to the surroundings, it is a myth that this rejected heat can be effectively used. The rejected heat is available at a low temperature, only slightly above ambient, therefore little effective use can be made of it. This is the penalty that the laws of thermodynamics impose on the conversion of heat into work.

eh, big deal (1)

friedman101 (618627) | more than 7 years ago | (#18057910)

my dog is the ultimate in power conservation. she gets energy from consuming her own heated waste.
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