in general . and what % of that waste is heat?

In an automotive gasoline engine, typically 70 to 75% of the energy is wasted as heat (exhaust and cooling system), sound (both exhaust and mechanical), pumping losses, and friction. The loss varies with engine operating conditions, and can be as high as 88% at light loads. Of course, at idle the loss approaches 100%.

[This message has been edited by Marvin McInnis (edited 11-30-2011).]

Well, that's going to depend on the engine. To know for sure you'd have to know the temp in the combustion chamber and the power out put of the engine among other things. Though, it seems the "general" value accepted by the industry is about two thirds or 66%

http://www.technologyreview.com/energy/37621/

http://www.engineerlive.com...es_into_steam/15633/

So in the last 100 years, how much heat have we put into the atmosphere with internal combustion engines? (technical question...)

That's a fun questions from a science point of view.

Note too that a similar question is 'how much heat have we put into the atmosphere from heating our homes / buildings?' Afterall all of that heat from our heating systems at home dissipates to the atmosphere as well.

Recall also that no energy is ever created or destroyed so we're not creating new energy that wasn't there before... just pulled it out from the gasoline, spent some two thirds of it (or whatever) as heat, and the rest as motion... and that motion (kinetic) energy of the vehicle ultimately got converted to mostly heat too.. after all you ended up braking to a stop right?

Some of the kinetic energy also goes into bending pieces of metal in accidents...

This is fun! But my point is that you can't say that we have heated up the earth by X joules of heat energy from the heat we wasted in all IC engines... that heat energy is getting used in so many ways.. but yes i think it'd be fun to dig deeper into this.

im sure its been more than enough to send someone through time!

(not delorean related bc 1.21 jiggawatts is equivelent to a bolt of lightening)

but im sure over time, man kind has produced enough waste energy to push a man through time. if we havent done it yet.

And then too let's not forget all that heat lost wasted just to make and get that gallon of gas to your local gas station. Oh yeah, and the heat lost out the top of your head when have to pay more than XX damn $ pay for just one stinkin gallon. The more you study it, the uglier it gets.

quote Originally posted by Gall757: So in the last 100 years, how much heat have we put into the atmosphere with internal combustion engines? (technical question...)

It's safe to assume that eventually 100% of the energy we have put into an internal combustion engine it turned into heat.

---
Tonight in Wisconsin the low temperature is forcasted to be 22 degrees. Sometime during the day tomorrow it is expected that the high for the day will be 36 degrees.

Now if we took every car in Wisconsin, and got everyone to drive down the highway at once, we couldn't even come close to warming this state up a single degree.

We can fill Lambeau Field with 73,128 people and it won't do anything to warm up the first row of cars in the parking lot.

The earth receives a huge amount of energy every day, and the earth also casts off a huge amount of energy every day

quote Originally posted by phonedawgz: We can fill Lambeau Field with 73,128 people and it won't do anything to warm up the first row of cars in the parking lot.

If the cars were parked above the field it would. You know, that whole pesky thing about heat rising.

quote Originally posted by tomsablon: how much energy is lost as waste in a gallon of gas? in general . and what % of that waste is heat?

Last I heard (2-3 years ago?) the percentage of energy captured by the most efficient internal combustion gas piston engine was about 28%. So 72% is wasted. One could calculate it out and figure out the percentage lost to heat, friction, exhaust, ect. But remember that one of the big losses is the mechanical design of the internal combusion engine.

When the fuel/air charge ignites, it has enough volume to fill more than it can. The piston gets to the bottom and that's it...it can not mechanically be pushed down any further...even though the cylinder pressures could do it.

The percentage may be closer to 30% efficient by now? There is one company that's claiming 50% efficiency with their design, but it is still in R&D. Here is a vid of the sewing machine.

And here's an explination

[This message has been edited by 1fatcat (edited 11-30-2011).]

quote Originally posted by phonedawgz: The earth receives a huge amount of energy every day, and the earth also casts off a huge amount of energy every day

Could you describe the 'casting off' process in more detail?

The casting off of energy (heat) is like putting a hot steak on your plate and waiting utnil it is cold to eat it. Exact same thing. Larry

Earth is designed to cleanse itself. There is no other place in the universe with the conditions of our planet. There are scientists looking to other planets to live but why don't we learn how to take care of our planet FIRST and THEN we can go and look at other places, if we need to?
With today's technology,we shouldn't be burning fossils, we should've have a car that runs on air! There is one, in France. But that is bad news for the petroleum giants. They have people who look for the ones with those ideas and buy them out and we the public never hear about it.
There is a lot of energy wasted as heat on piston engines, there's also a lot of energy that can be recovered under braking! Look at F1 Kinetic Recovery System (Kers), just to mention one.

interesting stuff.

It is safe to say that it is unreasonably high. You also have to remember that some of that energy is also converted into light, and also that 15% of the energy converted into kinetic form is wasted in the drivetrain. A guy by the name of Stan Meyers claimed he solved the problem of pollution and inefficiency. Apparently, he figured out a way to efficiently convert water into its base elements through electromagnetic resonation (much like how an opera singer can break a glass with sound) inside the combustion chamber. There's alot of doubt and skepticism on that one because many believe it would violate the 2nd law of thermodynamics, but his believers are still trying to recover his work. It was allegedly confiscated by the govt. after he mysteriously died.

114,000 BTU per gallon of gasoline

quote Originally posted by La fiera: Earth is designed to cleanse itself. ... There is no other place in the universe with the conditions of our planet.

??? Care to cite credible sources for those dubious factoids?

quote ... we should've have a car that runs on air! There is one, in France.

Sounds great ... air makes a cheap and handy working fluid, but where does the energy come from? Care to cite a credible source for that factoid?

quote They have people who look for the ones with those ideas and buy them out and we the public never hear about it.

Can you provide proof? Can you even cite credible evidence? Bulldust like this does nothing to promote real technological progress.

quote There is a lot of energy wasted as heat on piston engines, there's also a lot of energy that can be recovered under braking!

Yes to both, but there is a theoretical upper limit on the efficiency of any piston engine ... and it is well below 100%. The biggest problem with regenerative braking is, how do you efficiently store the recovered energy so you can use it later?

quote Originally posted by tomsablon: i Know that there is 3.414 btu's per electrical watt.

??? That doesn't make sense. The BTU is a quantity of heat energy, while the watt is a rate (e.g. BTUs per second).

[This message has been edited by Marvin McInnis (edited 12-01-2011).]

quote Originally posted by americasfuture2k: .... but im sure over time, man kind has produced enough waste energy to push a man through time. if we havent done it yet.

We produce enough energy (wasted and not wasted) to push all of civilization through time.

One minute at a time.

Marvin McInnis, the compressed air car link:
http://www.gizmag.com/compr...launch-in-2010/8896/

quote Originally posted by trotterlg: The casting off of energy (heat) is like putting a hot steak on your plate and waiting utnil it is cold to eat it. Exact same thing. Larry

I'm still stuck on this analogy. Is Earth the steak? Does the Earth radiate heat like the sun does? There is no atmosphere out there to transfer molecules.....like a steak has on a plate.

quote Originally posted by Gall757: I'm still stuck on this analogy. Is Earth the steak? Does the Earth radiate heat like the sun does? There is no atmosphere out there to transfer molecules.....like a steak has on a plate.

If that is true, then remember there is also no atmosphere to transfer the sun's heat to the earth. Heat does not need a medium to be transferred like say sound does. It can be transferred through a vacuum.

Originally posted by La fiera:

"Earth is designed to cleanse itself."

"There is no other place in the universe with the conditions of our planet."

Mcinnis quoted:
"??? Care to cite credible sources for those dubious factoids?"

Lets just use 2 examples on how the earth cleanse itself and see if they are factoids:

1) if you put something underground, it will decompose and turned into its original elements, whether it takes 1 hour or 1 million years.
2)The trees filter the air we breathe.

And no, mankind or any meteor will destroy the earth on 2012 or ever, unless its creator is a liar.

Credible source: "A generation is going, and a generation is coming; but the earth is standing even to time indefinite." (Ecclesiastes 1:4)

"There is no other place in the universe with the conditions of our planet."

Just look a some simple things like the size of our planet, its 23.5 degrees of tilt, its location in our galaxy, its gravitational force, the exact orbital distance from the sun, the influence of the moon's magnetic field, etc. All these have a positive direct effect on every living creature on earth whether is a single cell micro organism or human.
Is obvious that we humans don't have the slightest idea how much intelligence and wisdom it took to make this "perfect" planet our home. And even worst, some doubt that fact.

And for the ones that doubt that fact, here is the question that the earth's designer ask you:

"Where did you happen to be when I founded the earth?
Tell me, if you do know understanding.
Who set its measurements, in case you know.
Or who stretched out upon it the measuring line?
Have you intelligently considered the broad spaces of the earth?
Tell, if you have come to know it all." (Credible source Job 38:4,5,18)

I may not have the superior academic preparation or credentials you may have Mr. Mcinnis which is probably a good contribution to society; but the little I know I apply it logically and with common sense also contributing to society.

Rei Moloon




... we should've have a car that runs on air! There is one, in France.
Sounds great ... air makes a cheap and handy working fluid, but where does the energy come from? Care to cite a credible source for that factoid?

quote Originally posted by n7vrz: ... the compressed air car link: http://www.gizmag.com/compr...launch-in-2010/8896/

But where does the energy needed to compress the air come from? Even then, the energy density of compressed air is quite low ... even lower than conventional batteries.

quote Originally posted by Gall757: Does the Earth radiate heat like the sun does?

Absolutely. The black-body temperature of deep space is very low ... only a few degrees above absolute zero. The black-body temperature of the Earth, by comparison, is much warmer (~50 F), so it constantly radiates heat into the void. The radiant heat flux will be directly proportional to the difference in black-body temperatures, Earth vs. deep space. Even the polar ice caps are warm enough to radiate a lot of heat.

Consider your own experience. Have you ever noticed how much colder a winter night feels (and is) when the skies are clear? Without clouds to reflect some of the heat back, you are observing the environment around you radiating heat out into deep space.

[This message has been edited by Marvin McInnis (edited 12-01-2011).]

quote Originally posted by retroman: If that is true, then remember there is also no atmosphere to transfer the sun's heat to the earth. Heat does not need a medium to be transferred like say sound does. It can be transferred through a vacuum.

provided that the heat is radiated without opposition?

quote Originally posted by tomsablon: provided that the heat is radiated without opposition?

hummmm. I am guessing the opposition you are talking about is clouds (or what else would oppose heat radiation?). So what do we know about the % of Earth that is cloud-covered. Has it changed over time?

Quote from 1fatcat - "If the cars were parked above the field it would. You know, that whole pesky thing about heat rising."

Heat doesn't rise - heated air rises.

Quote from tomsablon - "provided that the heat is radiated without opposition?"

Heat is transferred primarily (approximately 98%) by radiation. If the radiated heat is blocked by an opaque object, it will be absorbed; if blocked by a transparent object, it will be transmitted. Once the absorbed or transmitted heat passes through the object, it will re-radiate until equilibrium is achieved.

Have you ever experienced feeling the cold from an opened freezer door from across the room as soon as it is opened, or heat from a woodstove as you walk past the doorway?

quote Originally posted by La fiera: Credible source: "A generation is going, and a generation is coming; but the earth is standing even to time indefinite." (Ecclesiastes 1:4) ... "Where did you happen to be when I founded the earth? Tell me, if you do know understanding. Who set its measurements, in case you know. Or who stretched out upon it the measuring line? Have you intelligently considered the broad spaces of the earth? Tell, if you have come to know it all." (Credible source Job 38:4,5,18) I may not have the superior academic preparation or credentials you may have Mr. Mcinnis which is probably a good contribution to society; but the little I know I apply it logically and with common sense also contributing to society.

This thread started as a technical discussion. If you want to discuss religion or philosophy, then I'm probably neither very interested in doing that nor particularly competent to do so; I don't think this thread would be an appropriate place anyway.

[This message has been edited by Marvin McInnis (edited 12-01-2011).]

quote Originally posted by Gall757: hummmm. I am guessing the opposition you are talking about is clouds (or what else would oppose heat radiation?). So what do we know about the % of Earth that is cloud-covered. Has it changed over time?

since heat can only be transfered by convection,conduction, or radiation and each having its own resitance to transfer. i feel in this case it would only be logical to ask the next dinosaur i talk to .

quote Originally posted by tomsablon: since heat can only be transfered by convection,conduction, or radiation and each having its own resitance to transfer. i feel in this case it would only be logical to ask the next dinosaur i talk to .

I take it that you would like this thread to get back on topic? Have you received a satisfactory answer to your original question?

this thread should be moved to off topic .no one knows the exact efficiency of a modern gasoline engine because there are now so many different types .the 30% figure comes from the 50's , give me a break .a typical 2L motor nowadays produces 140 hp NA .my dads old 283 CI pontiac v8 put out 185 hp somewhere in an advertizing agency's writers mind . you do the math .

the reason i asked this original question . what if you ran the output engine coolant hose going to the radiator through a heat exchanger that would boil say r-410 a refrdgerant have this refrigerant drive a refrigerant compressor in reverse(refrigerant drivein motor) that is mounted on the belt system so that the waste heat would constanty give an amount of force to the engine when ever there was significant waste heat. liquid cool the exhaust after the cat for some added heat . make its internals light .possibly withn a light pulley and a clucth disengage it to reduce drag when not utilizing waste .nothing fancy . something you could add to any car for a few extra free mpg. any remaining heat could continue on to the radiator for removal or recirculation back to the engine to keep normal engine temps. the outlet of the refrgerant engine could go to a condenser and then back to an end mounted condesate pump (of positive displacement type) to force liquid refrigerant back to the boiler for regeneration

bmw is working on a similar concept that boils the cooling water and uses a small steam turbine to aid efficiency .i like your concept though , may be more efficient in the lower RPM range .

i was thinking that maybe lower boiling temps and condensing temps might make it operate with smaller margins of heat than water)..possibly a dual refrigerant systen in cascade set up to exstact at lower weather temps. to eek out a smidgin extra in the winter. the other cool thing would be that anything on the belt system would benifit from the extra push.

i have to agree with you but i a am old school (make that really old ) suck squish boom blow kind of guy so i cant advise on thermal efficiency .