Crosswords1 min ago
Could A Hydroelectric Power Station Be Created Out At Sea?
Okay, I've got another idea about hydroelectric power that I could use some help with. Imagine you have an enormous funnel that is 1km in diameter at the top. This enormous funnel is held in place by four hollow towers (that are open at the top), that are cemented into the sea bed. The top of the funnel is just below sea level so that it is always half full of seawater. The spout of the tunnel goes about 250m down, where it splits four ways into tubes that feed the four hollow towers. Where the water feeds into the tower there is a hydroelectric turbine. The water keeps on falling after going through the turbine and falls into the hollow tower
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New Judge-Judy, Judy, Judy, I'm old enough to own a washing up bowl, as you should be able to tell from the Cary Grant reference. The system I'm proposing would have no water in it before the start of the experiment. The Funnel is lowered so that it half fills with water. The water travels down the spout, which splits into four. The water travels down these tubes into the towers(which at this point contain nothing but air). The first turbine would be placed just before the exit into the tower. Following the water down it would go through a second and third turbine. Now, when the water hits the bottom of the tower, yes, it would fill the tower up and make the whole thing redundant. But I'm asking, could the electricity from the second and third turbines be used to pump out the water before it becomes a problem?
\\ "the inward current can be traced ads far as crete" - I'd say there is a fair amount of water movement there//
So wd I - but movement is nt the operative concept - hey check out Carnot - he gets energy and power confused but Kelvin rewrites ,,,,
imagine squeezy bottle mummy gives you
[god thank god this isnt a Dom C thread, I wd have fwee complaints al ready - a large number anyway]
...squeezy bottle (*) and TTT squeezes it - the movement goes ever so far but you wont get much energy from a generator out of it
(*) fairy liquid or persil will do
and so it is really the height/fall that we are taking about - not lateral motion
and for anyone who does control volumes and energy ( quite interesting if you do this at any level ( pun there) above A level ) you will immediately see that the energy required to pump out the funnels before they fall - will be greater than any generated.
and hence bous and girls the second law will apply
wh most of us thought it would anyway
So wd I - but movement is nt the operative concept - hey check out Carnot - he gets energy and power confused but Kelvin rewrites ,,,,
imagine squeezy bottle mummy gives you
[god thank god this isnt a Dom C thread, I wd have fwee complaints al ready - a large number anyway]
...squeezy bottle (*) and TTT squeezes it - the movement goes ever so far but you wont get much energy from a generator out of it
(*) fairy liquid or persil will do
and so it is really the height/fall that we are taking about - not lateral motion
and for anyone who does control volumes and energy ( quite interesting if you do this at any level ( pun there) above A level ) you will immediately see that the energy required to pump out the funnels before they fall - will be greater than any generated.
and hence bous and girls the second law will apply
wh most of us thought it would anyway
Triple T- Yes, Gibraltar is British, no argument from me. Spain might have a problem, but as long as the people on Gibraltar want to be British, then Spain might as well be tilting at windmills. As far as tidal is concerned, yes, lunar gravitational energy is immense, but if the only way we can harness it is through tidal power stations, then I feel we are not tapping it's full potential. Even I, don't have a crackpot theory for this one! Yet. As for the dig about destroying a boat to make a raft, I like to think I would go full Hardy Krüger and make a plane.
copy of carnot here
not available on gutenberg
https:/
not available on gutenberg
https:/
Peter P - I understand nearly all of that, but there is a fixed amount of energy required to pump the water out. So one turbine might not work, as the energy created is equal to the energy needed to evacuate the water. That's why I would have two out of three turbines(three turbines per tower) dedicated to pumping out duties.
If I imagine a hose, the water comes out through the nozzle at do many gallons a minute. If an extra nozzle is added to the existing one, does the amount of water produced per minute not remain the same?
If so and half the power generated is required to pump out the water, surely it wouldn't matter how many turbines were used, there would be no net gain?
If so and half the power generated is required to pump out the water, surely it wouldn't matter how many turbines were used, there would be no net gain?
thecorbyloon-true, but I'm not adding extra nozzles or extra water. I'm using a single stream of water to power a turbine and then dropping that water another 200 metres to another turbine and then dropping that water 200 metres to the last turbine. I could add more turbines but I still only have that original amount of water to pump out. Therefore, there must be a point where I'm creating enough electricity to pump the water out.
What I mean is a certain flow of water will generate a certain amount of power.
You said, "So one turbine might not work, as the energy created is equal to the energy needed to evacuate the water."
If 50% of the generated power is needed to pump out the water, it's 50% still, regardless of how many turbines you have.
You said, "So one turbine might not work, as the energy created is equal to the energy needed to evacuate the water."
If 50% of the generated power is needed to pump out the water, it's 50% still, regardless of how many turbines you have.
thecorbyloon-okay, say I've got two turbines creating energy and it takes 50% of that energy to pump out the water. (I would happily settle for that.) But say I add two more turbines, thereby doubling the electricity produced, I've still only got the same amount of water to pump out. So I would be producing electricity and only using 25% of it to pump out the water, sounds great. Remember, this is an 'in line' system of turbines with no extra water or nozzles added.
thecorbyloon-I think your argument would hold water (sorry) if the deeper I go to add my turbines, the harder it becomes to expel any water due to the increased water pressure on the outside. If that's the case, then we are totally within the realms of Carnot and the laws of thermodynamics and the whole system is a failure. It just becomes a giant waterslide for any passing dolphins. But, I am not trying to expel water upwards, I'm trying to expel it sideways or downwards with the use of pumps and clever funnelling. Guess I need the opinion of a marine engineer who knows if any modern pumps are up to the job.
I'm becoming intrigued (and puzzled) with this!
So you're suggesting that the water from the bottom of the funnel is pumped back to the top, using electricity which is generated as the water "falls" through the funnel. Is that right? If so, it comes back to the same question: why will the water fall through the funnel? It will only do so if the water level in the funnel is higher than that of the surrounding sea and it will only do so then until the levels are equalised. But you said that "the top of the funnel is just below sea level so that it is always half full of seawater." It won't always be half full of seawater. It will always be completely full of seawater since it's beneath the surface. I'm sorry but I'm struggling to envisage your concept. If you are suggesting continuously pumping the water from the bottom to the top you have two problems: (1) the water has no reason to "fall" from the top to the bottom and (2) even if it did, the energy required to pump it back up would be more than the energy that could be captured by its falling.
When you talk about replicating the Hoover Dam, that structure holds back a reservoir of water (Lake Mead) that is continually replenished by the Colorado River. A constant head of water of over 700 feet (>200m) is thus provided to drive the turbines. Your scheme (as I understand it) provides no head of water at all and therein lies the problem.
So you're suggesting that the water from the bottom of the funnel is pumped back to the top, using electricity which is generated as the water "falls" through the funnel. Is that right? If so, it comes back to the same question: why will the water fall through the funnel? It will only do so if the water level in the funnel is higher than that of the surrounding sea and it will only do so then until the levels are equalised. But you said that "the top of the funnel is just below sea level so that it is always half full of seawater." It won't always be half full of seawater. It will always be completely full of seawater since it's beneath the surface. I'm sorry but I'm struggling to envisage your concept. If you are suggesting continuously pumping the water from the bottom to the top you have two problems: (1) the water has no reason to "fall" from the top to the bottom and (2) even if it did, the energy required to pump it back up would be more than the energy that could be captured by its falling.
When you talk about replicating the Hoover Dam, that structure holds back a reservoir of water (Lake Mead) that is continually replenished by the Colorado River. A constant head of water of over 700 feet (>200m) is thus provided to drive the turbines. Your scheme (as I understand it) provides no head of water at all and therein lies the problem.
New Judge-No, at no point is any water being pumped back up to the top. It is being pumped out into the ocean, near the sea bed. The funnel can always be half full (like my glass) because it can be moved up and down and tilted slightly. This would all be computer controlled to ensure that there is always enough water in the funnel to feed the turbines and also that it doesn't fill up completely(although that would still work). The water falls through the funnel and drops a further 250m,(like in the hoover dam) and exits into one of the towers. These towers are open at the top and full of air, so the water will fall down the tower. The first turbine is situated just before the water exits into the tower and would be comparable to the Hoover Dam as it has fallen over 250m. The electricity from this first turbine is sent back to Blighty. The water still keeps falling and gaining speed when it hits the second turbine,250m below the first. After that it falls another 250m and hits the third turbine. The electricity from turbine 2 and 3 is used to power the pump. After turbine 3 the water falls onto the propeller of the pump,100m below, which is used to pump that water into the ocean at seabed level. Is that any clearer?
// say I've got two turbines creating energy and it takes 50% of that energy to pump out the water.//
I wd happy to settle for that
so would I hur hur hur
it would take at least 100% and a bit more
which is why in very basic terms we are in a no win sitn ( 1 law) and a not even break even ( 2 law) situation
and the temp of the water would go up a bit ( where the extra energy went )
out of craziness came forth - er the second law of thermodynamics
not bad for a days work if you look at the endless and pointless DOm C threads
I wd happy to settle for that
so would I hur hur hur
it would take at least 100% and a bit more
which is why in very basic terms we are in a no win sitn ( 1 law) and a not even break even ( 2 law) situation
and the temp of the water would go up a bit ( where the extra energy went )
out of craziness came forth - er the second law of thermodynamics
not bad for a days work if you look at the endless and pointless DOm C threads
this doesnt look bad
https:/
there was a prog on tee vee where an O U lecturer calcuated the energy from the lake/generator electic system in Wales
pretty damn inefficient I recall ( diesel power is 27% and is the highest of the external generators )
https:/
there was a prog on tee vee where an O U lecturer calcuated the energy from the lake/generator electic system in Wales
pretty damn inefficient I recall ( diesel power is 27% and is the highest of the external generators )
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