2008 - and still the dominant issue is Energy and how to get it. One of the reasons this debate drags on is due to the ignorance (or mendacity) of the people promoting Green technology. This is because the physics behind the principles of Work and Energy is disguised or misrepresented for political reasons. A basic understanding of the relationship between work and energy would certainly help the general public to make their own judgement concerning the use of fossil fuels and the politics behind the control of energy sources.
The first step in understanding Energy is that Heat is the elemental form of energy so all energy can be expressed in terms of Heat. Heat energy which we most easily understand is the heat we can feel through our sense of touch. Being warm-blooded creatures, anything which gives off heat energy more than we do, feels warm or hot to our touch and anything less than our body temperature, feels cool or cold. In reality, we should be called hot-bloodied creatures because our body temperature is actually very hot compared to most other things on this Earth. If a fence-post or a door handle was our temperature at nearly 100 degrees Fahrenheit, we would snatch our hand away thinking it was on fire. Energy in this form, being elemental, is Entopic, that is to say, unavailable for useful work. Heat dissipated in this way is very wasteful but this is the downside of mammals having a high work rate compared to reptiles. This means most of a mammals energy is used in keeping its temperature at a very high level.
This should help us realise that most of the World's energy is simply used, one way or another, to keep ourselves warm. Maybe this is why the epoch of the Dinosaur lasted so long - there was very little wasted energy.
The most significant thing about this phenomena is that we tend to overlook just how much energy exists when heat isn't dissapated but instead, converted into useful work.
But how is heat made to work? Until comparatively recently, no one knew. If mankind has been on this Earth for a million years, we didn't discover how to convert heat into work for over 998,000 years.
When it was discovered, the power released by harnessing heat energy was found to be absolutely incredible. The men and the countries who discovered this technology, (Watt and Co) eventually became all- conquering demi-Gods. The discovery was of the same magnitude as splitting the atom. It gave those who had it, immense power.
It must be remembered that before the discovery of what is now known generically as the 'Heat Engine' the only supplement to Man's work output was the horse or ox. It was generally recognised that one big horse, like the Clydesdale or Shire horse, could do the pulling work of twenty men over a sustained period. Without the horse or ox, it took a lot of people to achieve quite simple tasks.
If the men had a horse, it would do twice the work these guys are doing.
It is incredible to realise, therefore, just what a Heat Engine actually achieves. For instance, a small 100 horsepower car engine, the type of engine which bowls you along the Motorway at seventy-miles-an-hour, is producing the same sustained work as 100 horses or 2000 men. This extraordinary feat is made even more remarkable once it is realised just what has produced this amount of power. A mere three gallons of oil or petrol holds enough stored energy, when burnt, to put the equivalent of 2000 men for an hour on that same field shown above. Judging by the size of the field, more than enough to finish the job. In a modern context, paying 2000 men $5 each for an hour's work to dig that field, would cost $10,000 whereas harnessing the stored heat energy in fossil fuel, would only cost $7 for three gallons.
With this in mind, it should not be too difficult to see that by turning fossil fuel into useful work is a fair exchange. The soot and smoke is a very small price to pay for producing such an enormous amount of work. The same can't be said for using fossil fuel just for warmth.
To illustrate the discrepancy between useful work produced from the burning of fossil fuels and the unrecoverable energy lost when the same fuel is used to produce energy for heating. Take an average house using a central heating boiler with an output of 90,000 btu. To produce the same sort of heat with electricity generated by a simple treadmill would require a treadmill capable of accommodating 700 men.
The worst aspect of using fossil fuel for heating is that being entropic, the need for heat is continuous. When heat is turned into work, the work stays done and does not need repeating, (a field stays ploughed) but energy created just to keep us warm requires costant topping up.
The point of this dissertation is to make it clear that it is not the Heat Engine in its various forms which is causing the rise in fuel prices or the ice caps on Mars to melt but the burning of fossil fuels to keep us warm. Where politics plays its dirty part in all this is the way it deceives the public into accepting that Heat Engine fuel, ie, automotive fuel, is the cause of the energy problem not heating fuel because Governments the World over can more readily levy tax on road vehicles than on heating fuel. The fact is, the rise in oil prices would stop dead if the Government promoted the use of vegetable oil or renewable carbon fuels for central heating systems. Remember, any old bio-fuel will do for heating purposes. They won’t, of course, because VAT on fuel ensures that rising oil prices means rising tax revenue from VAT.
Ah, but you have'nt considered the exception to your dissertation about the heat:work ratio...nuclear fission.
After initial cost, nuclear power, uniquely among energy producers, generates heat/energy for free.
So, in the long run governments may be cutting their own throats vis-a-vie VAT etc, because, unlike oil it is re-newable; esp if that nuclear energy is used to generate elecrticity that powers an elecrtic car for example.