"Energy neither can be created nor can be destroyed", then why do we worry about limiting reserve of petrol, coal and other resources?
Lot of research have been done on alternate energy.(Solar energy, wind power, hydrel power.)
Instead of using petrol, coal etc we should try to develop commerial method of tapping of energy and reuse it repeatedly.

Then get started on that.

I do need some energy.

The problem with all them alternatives is the same as with 'curent' energy systems.

As you transport the energy from where you get it, to where you need it...

Energy in the transmission media 'changes' state and leaches out of the system.

There is never quite as much at the 'users' end as was generated at the 'supliers' end.

O.K I start from today onwards and promise to give you my package free of cost provided you don't mind please.

The problem is not that energy is destroyed, but that it gets to a state in which we can't use it.

This process is called entropy.

If you take a ball that is 100 feet high, it has energy. If you drop it, and it hits a pedal that powers a sewing machine, you make it into useful work. But after that useful work was used, to sew a shirt, for instance, the energy that has been converted to the work to run the needle through the material, can not be used again. The thread is in the shirt; the work is in the thread's passing through the shirt. You can't take the thead, and make it move backward to raise the ball 100 feet high.

This is the basic explanation.

The more scientific one is that energy, when you want to convert it into work, does not 'leak' or 'seep away', but goes through a process that is not reversable.

The crux of that statement is that there is no coldness, only heat. If you close the door in the winter to keep the cold out, you are not doing that, you are closing the door to keep the heat in.

Once you heat up an object, it can only be cooled down by heating up other objects that are cooler than itself.

So when you open your front door in the winter, your house loses heat, by that heat giving its heat to the outside world.

Because you can't cool down an object without heating something else up, eventually, very eventually, in trillions of billions of years, all the material in the world will be one, even, equal temperature.

Now. Consider that you can't get energy converted from a ball by simply releasing it. You get energy out of it if it falls 100 feet; but if it is sitting on a table, and you release it, you can't get it to give you work. Even if the ball that drops 100 feet and the other ball that's on the table, are both at the same height. (The table is 100 feet up.)

This is absolutely true for all conversion of energy to work: to get energy converted to work, it has to go from one energy state to another.

And for that, you must have a situation in which a body, which has energy, can go to a state of a lower energy, and the process can be used to make work.

Then if the the work is so that it can't give the body its energy back, then we lose USEFUL energy, we don't lose energy per se.

So: eventually, when all material has fallen into one, or spaced out flying into the infinite distance, AND all material has the same temperature, then no energy is available to make any work, or, in other words, to make any change in the world. That is the world that ours will eventually become, if we wait long enough, and there is nothing we can do to reverse the process.

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In a small way, here, on Earth, the same thing is happening. Gasoline has a lot of stored energy, we convert it in engines to work (to make cars and trucks to go from point A to point B), and we did not lose the energy, but we can't make new gasoline by allowing the cars and trucks to go from point B back to point A.

The energy has not been lost, since our cars and trucks are in point B, which is better for us than if they were still in point A, but the energy we were able to use was lost to us. We can't use it again, though it did not disappear to the physical world.

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The problem with solar and wind energy is different from the energy disappearing for good to our use. Wind and solar power depend on the sun and on the wind, both of which are generated by the sun. So there is no need to worry about the source going depleted, for the next half a billion years. The problem is that the energy we gain from fossil fuel is cheap, portable, does not have loss in portation, keeps, is dependably constant when burnt, so we can relyo on their performance and can precisely engineer stuff that burn it to create precise work. The alternate energy is very weak; very, very weak. You need an acre of land to convert sunshine into useful energy and we need to do this for a whole month, to get the equivalent energy to what is useful to us in five ounces of gasoline.

This means that if we wanted to emulate the energy we use with burning gasoline by using solar panels; if we were to supply our entire energy needs in our nation and on the entire planet, only by installing solar panels, we would need an are the size of ten times Jupiter for the sun to shine on.

And that includes areas where the sun don't shine.

So the solar solution is not very sustainable.

The wind solution is more sustainable, but you need a HUGE initial investment, for the energy gain is also small that you get from each wind turbine, and to top, there is no wind all the time, so five times the entire plant of employed wind turbines must be built to ensure that there is enough energy produced at all times; the plants must be large in area, and far from each other, to make sure that at least one of them gets wind at any given time; the land area they occupy is lost, for their bases need a good, deep, wide foundation; the best area for wind turbining are either unarable desert ground, or low, shallow water, for there is no farming there, so no precious agricultural land is lost; and in shallow water the building of turbines is not too costly. The Arizona deserts, James Bay in Canada come to mind, the Canadian Arctic. In Europe, there has already been a few very large plants built, the bulk of them in the Baltic Sea and the Caspian Sea, for those are shallow.

There is no easy, cheap solution, the next cheapest to gas burning is nuclear plants, but they are bad for your health. On a cosmic scale, which is trillions and billions longer than our individual lifetimes, the world will attain an even temperature, and there will be no differences in energy to conver to work, so it will become a very boring place. Just matter, floating, or being crumped together.

Relax, matter will be just as happy then as now... and if you consider humans, and their lives, then I venture to say that the combined amount of unhappiness and happiness will be shifted toward the "happier than not"; that is, the total happiness then will be higher than the total happiness now, even when given that no sentient beings will exist.

People could move into caves or build their houses underground. The temperature is pretty much maintained in most places.

I saw a world where there were no cars, no fossil fuel. People still got around in horse drawn and ox drawn carts and farmed their own food, and raised their own meat. Trains were run by steam I think. Everything was natural and calm. It was lots of hard work but people were not fat and over weight or lazy and kids did not sit around texting each other. Wars were not fought with bombs and guns. They just beat the crap out of each other with sticks or swords.

It was nice.

Wux is exactly correct. When it comes to using energy to do work, it doesn't matter that energy can't be created or destroyed, what matters is that useful forms of energy (like the chemical energy stored in petroleum) are irreversibly turned into less useful forms of energy.

Wux said:

"The problem is not that energy is destroyed, but that it gets to a state in which we can't use it."


Ahh yes! That's the state of my energy.

We can convert mass into energy and I think equation is as given by great scientist Einstein, E= mc2. Is reverse also true, ie can energy be converted into mass?

Yes, energy can be converted to mass, and this happens in our supercolliders. It's been theorized that we may one day store energy in the form of particle/anti-particle pairs (with the anti-particles held in a magnetic bottle). Creating even a tiny amount of matter takes a huge amount of energy, so this doesn't have much use outside of research.

Anyone know of any situation where we are creating new matter out of energy, an then using that matter - outside of a research setting? (Not counting the change in mass for already-existing matter...).

This is actually only 1 line from the entire quote by Einstein:

"It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing -- a somewhat unfamiliar conception for the average mind. Furthermore, the equation E is equal to m c-squared, in which energy is put equal to mass, multiplied by the square of the velocity of light, showed that very small amounts of mass may be converted into a very large amount of energy and vice versa. The mass and energy were in fact equivalent, according to the formula mentioned above. This was demonstrated by Cockcroft and Walton in 1932, experimentally."

This was meant to help understand the relationship between mass and energy at the atomic level and does not literally translate to concepts of consumable or renewable energies. When fossil fuels are burned the total mass of the fuel is not converted to energy. Combustion only converts the heavier hydrocarbons to other molecules having less mass the energy that is released from gasoline is only a fraction of the energy stored in the molecules. We are no where near the technology required to fully convert mass to energy in a productive manner. The closest we have come to large scale conversion of mass to energy is for purely destructive purposes.

The scientific principal you are actually dealing with is ...


"There is no free lunch".

The closest thing to free energy would probably be geothermal. The Earth produces heat from radioactivity which then turns into heat which is eventually radiated out into space.

Man's use of geothermal energy just reduces the amount of heat directly radiated into space by a very small percentage but he makes up for it in oh so many ways. Geothermal use has almost no effect on climate or the planet in general if done properly.

Then how is nuclear energy actually created?

I can think of about half a dozen completely different answers to that question. Can you be a little more specific? Do you want to build a bomb? create a Sun? Hold matter together? Make electricity?

This is exactly what I had thought for the longest time. It turns out that if you burn a match, and measure its mass before the fire and the particles that it becomes after the fire, the masses will not be equivalent.

This is even harder to get your mind wrapped around. If you elevate a poing-poing ball with your hand about a foot, then its weight will be smaller due to being farther away from Earth's centre of gravity, but its mass will increase because its energy state has been raised by lateral energy store.

To muddle the issue, the increase is mass is ONLY in relation to objects that are in earth's gravitational field.

You can say everything is in Earth's gravitational force, so the day is saved, righ? Well, right. The earth's mass ought to stay constant with this change, when you factor in the energy change of the poing-poing ball, right? Right!! Because i if you work out the math, the energy gain and mass gain will cancel each other out neatly for the objects that are in Earth's gravitational field.

But the fact remains, that, Canada for instance, burns up in chemical and other forms of energy usage, about 1 kg of matter every year.

This means the earth, on the average, loses about a metric tonne or two in mass, due to energy conversion by humans for their own purpose only, but without losing any material to drift into space in this process.

Those who worry about Earth becoming an anorexic planet in the Solar System sense: Please relax, in the knowledge that debris from space that come raining down on earth as meteorites, sunshine and other sun rays, radiowaves, pulsar-emitted gamma rays, space dust and Heralds of Angels, way more than offset this loss.

In fact, the earth has been gaining weight faster than I, although I have been no slouch in this area of human endeavour, either.

What does this mean to us in a practical level?

That each day you step on the bathroom scale, your shown weight does not correspond exactly to your mass the previous day; you will weigh in heavier, without having gained any mass (or without having gained "weight" as spoken on street-level colloquialisms), since the pull of earth's gravity is increasing constantly with time. Well not constnatly, but near emough for our measuring instrument, the kitchen or bathroom scale.

Don't go running to GoodWill with all your "before" clothes, though, having heard this. The weight you gain to this above downscribed effect, is 0.000739 picogramms per year, which can only be calculated, but not measured by any instrument or scale or balance, because the instrument would need to be accurate to21 significant digits, which is stupendously hard to even imagine.

Make love, not electricity. I think this is what JB was alluding at.

Seriously, nuclear energy can't be created. Energy can be converted to nuclear energy by sticking gamma particles back into depleted uranium atoms by hook or by croock. Or tearing a helium atom into two deuterium atoms. That's a bit tough to do too, but in Hungary that was a grade seven physics project in my highschool. I got a C- for my work. "Diligent effort by student, but student failed to achieve objective." "Student gets "PASS" grade, but his report card will be released to him only after his parents pay for the seventeen-mile radius area in which all living things and humans perished, as a dirct consequence of the explosion(s) which were effected by the student's processes for the project."

Most of the heat produced by the Earth is not actually produced, and very little of it is due to radioactivity. The heat stored in the Earths core is energy left over from the formation of the planet. This heat is stored, below about 25 miles of the Earths crust, in the form of molten rock known as magma. That heat, 1000's of degrees, is pretty well insulated from us by the Earths crust. The technology to drill deep enough into the crust, in most areas, to utilize that heat on any commercial scale is not cost effective at present.

While geothermal energy is useful in some areas, it is a common misconception that geothermal energy takes heat from the ground and that heat is directly used to heat buildings. While this is possible in certain areas that are usually volcanically active, for most areas geothermal energy is only a supplement.

In most areas the temperature below the "frost line", usually not more than 4-5 feet below grade, is fairly constant year round. That temperature with slight regional variations is about 54 degrees Farenheit. In most areas that is the temperature that the geothermal wells are designed to collect and transport to the surface for use to heat buildings. Heat pumps are then used to raise the temperature to a point that it can be used to provide warmth.

As a Certified Well Driller, I am familiar with the installation of the geothermal wells and the subsurface temperatures. I am not completely versed in the operation of Heat pumps other than the fact that most of them are electrically operated and they require a minimum input temperature somewhere around 45 to 55 degrees to operate efficiently. For this reason most of the geothermal systems, residential and small commercial scale, are only financially viable alternatives in areas where the electrical costs are not prohibitive.

Geothermal can be also be used for cooling applications and it's efficiency for cooling is a lot better than its efficiensy as a heat source.

There are also non-electric grid powered space heaters, of which the Sun and the original big bang are but only two examples.

There are a few problems with your "burning match" statement. When you weigh the match you are getting a "weight" not a "mass". weight is a function of gravity and does vary depending upon the force of gravity at the point taken. Mass is often confused with weight, because weight is used to determine mass. The mass of an object is not a function of gravity and is constant whether the object is on the Earths surface or in the "zero gravity of space".

Setting that aside because if the weight before and after burning were both taken at the same location the would be an accurate comparison of the mass before and after. The next flaw in your statement is you are only weighing the "mass" of the match, the act of combustion, burning, causes some of the mass of the original mass to be converted to energy in the form of heat and light. Some of the mass of the match is also lost when carbon and other chemicals in the solid match combine with oxygen in the air to form gases, such as carbon monoxide and dioxide. Since you can't collect and weigh those parts of the original match you can't accurately determine the amount of mass that was actually converted to energy, some of the mass was not converted to energy it was simply changed through a chemical reaction to a different compound that still has mass.

In theory you are right, but in practice, you failed to achieve your objective.

Nowhere did I say `weigh the match.`.

I said this, quote from the post:

`It turns out that if you burn a match, and measure its mass before the fire and /that of/ the particles that it becomes after the fire, the masses will not be equivalent.`

The more careful reader would have noticed that I said `measure its (the match`s) mass`, and I did not say `weigh the mass` as you allege.

Diligent effort, but only good enough for a C-.