Quote:
Originally Posted by marki
Malcom I am against anything to do with destroying resources that cannot be retrieved. The burning of coal, LPG and crude for energy is criminal in my view. From the perspective of chemistry there are so many essential compounds that we simply cannot make in a lab that will be lost when these fuels are exhausted. The only other viable source is trees, what next a new global easter island? We only have small reserves of uranium and I will bet as soon as we use that up another essential requirement will be found which we will not be able to do due to lack of resources. The sun has powered this planet for millions of years, when will we the "wise ones" work that out. The technology is here now though expensive as it may be. What will be the cost of going on our merry way? I do not believe fusion will ever be a viable source of energy on Earth but why bother? we have a great big burning star thats doing all the work for us.
Mark
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I agree there, Mark. There are far more important uses for the crude oil and LPG than burning the stuff. However, solar power, as it is at present, is not our definitive answer. I've said it previously, it is not an efficient enough technology to be considered to be used as a base load energy supply source. It's greatest asset, sunlight, is also its greatest liability. Plus, we don't have sufficiently advance energy storage technologies yet, to be able to store what energy we do capture. Even the best of the sun based technologies is only 25% (at the very most 30%) efficient in capturing and even less for storing the energy gathered. You only have to look at the power requirements for a city the size of Sydney or Melbourne to see how impractical, at present, this type of energy generation is. Especially where using the present methodologies for generating and distributing power are concerned.
What we ultimately need is a solar PV cell which can harness 75-90% of the light impinging upon the cells and a far more efficient (and safe) storage technology than what we have at present. A typical house would use around 20Kw of energy to run all the electrical systems within it. Each square metre of the Earth's surface has 1370W per square metre of solar insolation. That means 14.6 square metres of surface area intercepts 20Kw of energy. At 75% efficiency, it means you'll need about 20 square metres to intercept that amount of energy. The roof of your average home could easily accommodate a PV panel of that size. Now, if we can achieve this sort of efficiency and also develop the batteries to store it, then we will be getting somewhere. The really big thing about this is that we don't have to rely on centralised energy generating utilities if we can do this. No need for greedy energy corporations, except for the industrial sector, possibly.
Using our present technologies (including those solar furnace power stations), you would need impractically large areas set aside for energy generation of a magnitude large enough to act as a main supply.
And...what are the environmentalists going to say about it all, when you're mining all that silica sand and such to make all the mirrors, etc, for these plants?? If they find anything they disagree about, they whine. Next minute, they'll be complaining the solar plant takes up too much space, or you've had to mine 100KT of pure sand (or whatever else you might use) to make the mirrors. You're disturbing the habitat of the Itchy-goo bird!!!. Or the endangered pink spotted sabretooth hopping mouse!!!!.
You can see now, this is more complicated than it looks. Some things might look good on paper and in small to medium scale trials, but it's the really big picture that we have to consider. That's where things don't look so rosy and where we have to spend our research money to get things going.