It's obvious from the previous comments that some people are unfamiliar with basic terms necessary to understand the problems related. Let me elaborate on some of them:

EROI (EROEI) - energy return on energy investment. It's a ratio that describes how many joules of energy you get per joule invested into the production. The higher, the better. Early oil fields had as much as 100:1. Current conventional oil is (roughly) estimated at 10:1. Nuclear energy is estimated 4:1, oil shales are even worse. Bioethanol is actually about 0.9:1, so it's not an energy source at all (just a form of unfavorable conversion of fossil fuels into ethanol). Depends of course on many factors - these are only examples, the concept itself is important.

Net Energy gain - The amount of energy supply left after subtracting production, transportation, refining and other energy costs (let's keep money out of the equation). It's the only thing that matters - growth in net energy gain most often means cheaper everything and economic growth, and vice versa. Note that when moving to resources with lower EROI (from oil to shales, or coal), you actually have to produce more to sustain the same net energy gain - that's the biggest challenge today, together with production decline of depleted oil fields.

Exergy - crucial term, the energy in a system available for useful work. Unlike energy, which is always constant in a closed system (law of energy conservation), the exergy decreases with any process that involves temperature change. Note that this process is irreversible - if it was reversible, perpetuum mobile would be possible and laws of thermodynamics would not be valid. Example - you have a galon of warm water and galon of cold water. This system has an inherent exergy that can be used to generate mechanical work. However, once the water is mixed and the temperature equals, the exergy of the system will be zero, while the energy will still remain the same. This principle directly implies that energy cannot be "recycled", that the amount of exergy we can extract from Earth resources is finite, and in effect, that perpetual growth both in population and industrial production is a physical impossibility.

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

... we will have to get used to whole new levels of energy efficiency:

Basically, we have one Earth, of a fixed size, and no matter how we try, we will never be able to produce an infinite amount of energy and food from a finite resource.  So sooner or later, unless we drastically cut population growth right away (which looks extremely unlikely) we will have a population crash.  Simple as that.

One finite Earth and resources does not allow exponential population growth forever and definitely does not allow infinite human population.  We have almost kept up with the food and energy resources required so far, more than any other species, albeit with many on starvation rations.  But we have only put off the day when we just won't have enough, and will suffer the fate of every species that reaches population numbers that can't be sustained.

Best regards,
Steven.

Yeah.  Because of the basically certain result of our overpopulation, I am seriously considering not having any kids, but just to do my best to help others the best I can.  We can still live our lives in the moment, doing the best to be kind and help people, especially focusing on our nearest and dearest, but not restricting ourselves to be kind to just them.  When it comes down to it, the quality of one's moments is more important than the quantity of one's moments.

After all, does it really matter, in the grand scheme of things, for us personally to have had high quality moments, and to have positively contributed to our world to the best of our capabilities, if we can't control everything?  You just have to do the best you can, with the tools you have at your disposal, and the rest you just need to, with all the wisdom and humility and kindness of the best parts of the human race, say: "So be it."  Why worry about things you have no control over, if you have done your best?

That's my POV.

Best regards,
Steven.

Overpopulation is only a problem in the developing world, it's established scientific fact that once a country escapes poverty it's population growth rate shrinks rapidly and in a lot of cases becomes negative. The reason the western world accepts so many immigrants is mostly to prevent labor shortages resulting from shrinking and aging populations. You can't have more retired people than workers supporting them.

Poor countries may continue to grow in populace but they also have high death rates, consume next to no resources, and have low emigration.

Also all renewable resources like solar, tidal, and wind are called renewable because they are by definition infinite and will in practical terms never run out. As technology advances we are also not limited to resources found on Earth, asteroid and lunar mining might be economically and scientifically viable within less then 50 years. The main restraint on this would be lack of need due to abundance of minerals on earth. The reason we don't as a species use renewable or space resources is because we already have abundant and incredibly cheap resources all around us, if that changes then we will expand into the less productive and more expensive but still viable other forms of resources.

So don't worry about having children and contributing to overpopulation StevenAus. I would worry about the prohibitive costs of raising children in the developed world far more. 

DsRaider - To your contribution, I can say only this - you are absolutely, utterly ignorant of the practical problems of energy production. Why do you think nations wage bloody wars for every oil well that can be found? Because the most important matter, EROI and concentration of the resource, matter very much. 

A simple example for you: imagine you have a barrel of oil on an ocean shore. You have a concentrated, useful source of energy that can be used in many way. Now imagine you spill that barrel into the ocean. Suddenly, an energy resource has turned into a waste, a problem. But why? Sure the oil is still there, nothing was destroyed. Why can't it be put into that barrel by some miraculous technology and used as intended? If you study physics deep enough, and familiarize yourself with the EROI concept, you will find out that it's not principially possible. When entropy increases in the system, you can decrease it again only by spending energy. After a certain point, the energy cost of concentrating the energy resource is higher than the energy that resource can provide, which negates its usability. 

Why do you think all that enthusiasm about algae biofuels has gone quiet? Algae contain usable lipids, but the cost of extracting it and concentrating it is so high it has little practical use. EROI and net energy - two key terms. Study them, and you may come from your kingdom of technomessianist dreams into a real world where energy is limited, hard-to-come-by and finite. 

No, not having children is a personal, or personal/partner, choice.  It's just like saying that not trying professional chess is giving up on life, even if you are quite good at HOMM or other turn-based fantasy, or not running a successful business if you can handle money well is giving up on life.  And as I said, you don't have to have children to have a positive influence on the world, and to care for people.  Every environment has a maximum population it can support, and right now we are wiping out many other species just so we can expand our exponentially growing population even more.

It is not surprising that the idea of having no children is not very popular, given there is such pervasive and all-compassing social conditioning that applies in all areas of our lives, that the only socially acceptable reply to people doing something as significant as bringing another soul and mouth to feed (who could then bring even more mouths to feed, themselves later on) into the world is "Congratulations, how wonderful!".  Normally there is a choice to how you feel on any issue, but as societies we have guiltified people to the extent that there is no room for individual opinion any more when it comes to the very important choice of whether to add children, and thus adults, to the population of a planet that is already bursting at the seams (to put it mildly).  Why should human overpopulation deny the right of all those other species to live, especially when those other species respected reasonable environmental limits?

Best regards,
Steven.

Although the resources used for each child in the first world is a *lot* higher.  And the reason I was considering not having kids was not to do with not getting economic benefit, but not wanting to bring them into a crowded world that would not have many positive opportunities.

Best regards,
Steven.

Actually, I prefer the more rugged 'polar bear' and 'grizzy bear' brands over 'panda gas.'  They just make a more robust oil and gas product.

Besides hydrofracking will pollute the water tables with unknown (to the public) 'proprietary' chemicals so the bears ware better off as petrol anyway.

So, months have passed, I believe it is a time for an update. Meanwhile, the depletion of the most critical resource did not stop, the economies around the world would like to grow - but there is not enough energy for everyone. That is very well reflected by the rising price, that once again approaches the 2008 levels. Once it crosses a critical threshold, I believe we have a new 2008 with demand destruction, bankruptcies, job losses, stagflation and depression. The long-touted perpetual growth will be replaced by downward stairway - from one depression to another, through short periods of stagnation.

At the same time, the western countries continue in their aggressive, militarized campaign to secure the dwindling reserves. Decided to deny the problem to the last possible moment, the west once again prepares to use force to wrench the oil from the states that still have it. It was interesting to see the diplomatic "artillery preparation", when USA cleverly persuaded European Union to implement sanctions against Iran (based on a study from "Foundation for defense of democracies" - don't laugh, that one is real - saying that sanctions won't cause oil price increase. It was, of course, a blatant lie). Now the sanctions has backfired, and recession-hit EU countries must cope also with even sharper increase of oil price. (EU administration is very good in shooting itself in the leg).

Meanwhile, the greatest threat to the worldwide security - the state of Israel, having dozens of nuclear warheads in its arsenal - began a very aggressive campaign to attack immediately. Netanyahu mocks all efforts to resolve the matter peacefully, and proposes immediate attack. I am not sure most people are aware how perilous moment this is.

A few errors there.

Ahmadinejad threatened Israel. Ahmadinejad has threatened to close the Strait of Hormuz. Ahmadinejad (and the other oil producing states) profit by frightening the market and driving up the prices per barrel, not Israel.

Oddly, just published this today:  http://drjbhl.joeuser.com/article/419508/Purim_Esther_and_what_is_concealed_in_plain_sight

Netanyahu mocks nothing. He's charged with the security of Israel and the lives of half the Jews on earth. "Never again." means a great deal.

Israel has never made a nuclear threat against anyone. 

Israel did not begin it. Ahmadinejad is bent on the destruction of Israel and another Holocaust and has declared that publicly.

The attitude (election year, don't rock the boat - never mind the boat is sinking) he is met with is reminiscent of The Munich Conference of 1939, and Neville Chamberlain - from a psychological perspective.

"Containment" isn't an option with Ahmadinejad, just as giving Germany Czechoslovakia was not a viable option to keep Europe at peace.

Appeasement does not work with terrorists and fanatics, nor with anyone else for that matter.

What the fuck.

The only one of the three monkey's you listed that could even tacitly be referenced in such a way is Egypt's Mubarak.  The Assad family and Kadafi are both long standing antagonists, you might as well put North Korea and Iran in your list.

Educate thyself.