|
|
Post by rsmith7 on Mar 21, 2011 19:45:38 GMT 1
The problem with tidal energy can easily be seen by a brief perusal of the tide tables. If they used tidal turbines ( and wind ones) to pump compressed air to storage cylinders at each house, and/or used the electricity to operate night-storage/hot water heaters then there may be some point. Otherwise they are just injecting 'noise' into the grid, which makes it inefficient and so, more expensive. Not quite sure what you are driving at Carnyx. Energy produced in one location is of course going to ebb and flow with the tide, but if you think on a big enough scale and link many locations the energy production would be virtually seamless. And Mr Smith said: No doubt much the same was said by candle makers and oil lamp wick suppliers way back. Someone has to start somewhere. Indeed - you need to start with a tidal stream that contains fifty times the energy of the pentland firth. Sadly such a place doesn't exist. What part of "energy density" don't you understand? |
|
|
|
Post by jonjel on Mar 22, 2011 10:19:15 GMT 1
I understand it Mr Smith.
What I was trying to put over was that all technology has to start somewhere, and it is usually expensive in the beginning.
I have no doubt that if 75 or more years ago wind turbines had been suggested as a source of power the idea would have been scoffed at. Modern materials and methods of production have had an impact.
When the first digital watches were sold they were enormously expensive. Now they are given away with petrol.
And it will be the same with undersea turbines. Expensive to start with, but if the demand is there, they will eventually become an economic reality. You don't need to run them as fast as those on full hydroelectric plants, you will get the same energy from a big slow turbine in slow running water as you will from a small fast one driven by high pressure water.
And your comment that the would only be viable if they cost £3000 each and could be dumped overboard as a daisy chain might not be so far fetched after all.
|
|
|
|
Post by carnyx on Mar 22, 2011 11:49:55 GMT 1
jonjelWindpower is not a new technology. It has been subject to considerable thought and development for centuries by thousands and thousands of minds. Given the energy-density of the medium, and after having enunmerated all of the practical configurations of apparatus, the major issue is the materials. All that has really progressed over the past 300 years is the materials, which have become a bit lighter per strength. For example it is sobering to realise that even today a bridge of a given capacity made of modern steel will weigh the same as a bridge of equivalent capacity, made of wood! It is also sobering to realise that, as mass-production volumes get really large .. the individual product costs are driven by weight. For example, the business of sharing the economics of car production is done by weight of components ans no tny complexity. E.g. a set of wheels are 'worth' more than gearboxes. So, the only way that wind/tidal generators can develop is by considering radical new materials. And having caught up with fibreglass, ( which is short-lived stuff BTW) that's about it for Wind ( and Tidal) Without subsidy to build them, ans subsidy to run then, these things wou;d never have been built and are millstones round the neck of futiure generations. They will soon cost more to maintain than they generate. They are an appallingy cynical con.
|
|
|
|
Post by principled on Mar 22, 2011 13:46:28 GMT 1
I went to a meeting last week where a number of the speakers were from the large producers of power turbines, driven conventionally or by renewables. A couple of interesting points came out:
1) As yet, no company has managed to produce the huge wind offshore turbines that are to be installed in the North Sea. The issues weren't discussed, but that statement was made.
2) The problems with the gearboxes (the Achilles heal of wind turbines) will be overcome by the use of permanent (50 tonne!) magnets with no gearbox.
3) Thought is being given to using high voltage DC and then transferring this on shore from a group of generators before converting to AC. This reduces the switching complexity on each turbine, apparently.
P
|
|
|
|
Post by Progenitor A on Mar 22, 2011 14:27:30 GMT 1
No doubt much the same was said by candle makers and oil lamp wick suppliers way back. Someone has to start somewhere. I liked the optimism of Alexander Graham Bell. He invented the first telephone, but was there anyone to call? |
|
|
|
Post by carnyx on Mar 22, 2011 17:02:23 GMT 1
Apropos the telephone I was in a performance of G&S's HMS Pinafore the other week, and was amazed to see a reference to the telephone in the score. As Pinafore's first performance was only two years after Bell's first experiment ... and only one year after Bell demonstrated a workable system to the Post Office in London, it shows how well-up on technology Victorian society was ...
So to answer your question .. he didn't have to wait long!
|
|
|
|
Post by Progenitor A on Mar 22, 2011 18:36:58 GMT 1
So to answer your question .. he didn't have to wait long! Yes, but it was a wrong number. Question: Which came first, the telephone queue or Viavaldi? |
|
|
|
Post by mak2 on Mar 22, 2011 20:09:31 GMT 1
Vivaldi, by 1004 seasons.
|
|
|
|
Post by Progenitor A on Mar 23, 2011 9:20:21 GMT 1
Vivaldi, by 1004 seasons. Good one! ;D And not too far out in time either! |
|
