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Hydroelectric Power From The Sea? (Yes, But It's Bin A Year And I Think I Got The Science Right This Time)?

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crankfwd | 16:32 Mon 02nd Aug 2021 | Science
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I think we can use ram pumps to solve the energy crisis. First we build a hollow cylindrical tower out at sea, to a depth of say 1100m. The tower is open to the air at the top and has a sealed base at the bottom. We drill a hole about 20m below the surface and feed water into the tower. The water falls down a pipe for about 200m where it powers a turbine that is connected to an electricity generator. We collect the water and drop it down a pipe for another 200m to another turbine. We do this twice more until we are getting electricity from four generators.
We then drop the water another 200m to power a turbine which drives a cog that is geared to turn a disc at the base of the tower. The waste water from the last turbine starts to collect at the bottom of the tower creating a shallow reservoir that we need to pump out.
The rotating disc at the base of the tower has cams along its edge. These cams are used to push pistons outwards. These pistons are in cylinders built into the wall in a circular formation. The cylinders are sealed at the interior side apart from where a piston rod enters to push the piston outward. The outside of the piston head is exposed to the deep sea water.
The cam will push the piston outward against the high pressure deep sea water. An inlet pipe will take water from our shallow reservoir which will be pulled into the space created in the cylinder, behind the piston head. When the cam releases the piston, the low pressure water inside the cylinder will be the only thing pushing the piston out against the high pressure deep sea water.
This is when the system acts as a ram pump.
The piston will be forced inward and will force the low pressure water back out through the inlet pipe toward the reservoir. The inlet pipe will now act the same as a waste pipe in a ram pump and the flowing water will shut a waste valve. The remaining water in the cylinder will be forced through a check valve into a pipe and upwards to the surface.
The larger the diameter of the tower, the more cylinders that can be built into the wall at the base of the tower.
I realise that the ram pump cylinder will pump more of its water back into the reservoir than it sends to the surface but we can always add more cylinders to the system. We can even put another layer of cylinders above the original ones as ram pumps still work underneath shallow water.
I think we should be able to pump water upwards at the same rate that it falls into the bottom of the tower and so keep the reservoir nice and shallow.
Now, if I understand the maths correctly, we might only be able to pump the water near to the surface. In that case, we can pump the water into a reservoir tank (inside the tower) and use the electricity generated by the first turbine to pump out the tank.
This will leave us with 3 generators worth of electricity for every tower built.
Would this work? Everyone, please comment.
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your name's not Heath Robinson is it?
Correct me if I'm wrong, but I believe we've done something very similar to this on here before.

I think we concluded then that the energy needed to shift the water out of the bottom of the cylinder would far exceed any energy developed by the turbines.

You can't get 'owt for nowt.
Unless your on benefits NJ.
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NJ-yes that was me. But this time I am using the immense pressure of the deep ocean to move the low pressure water from the bottom of my tower. I'm not using the electricity created by the first four turbines. I am using the last turbine to move the 'camdisc' in a circular motion. The water collecting inside the bottom of the tower only has the air above it but the water outside the bottom of the tower has the ocean above it.
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Sorry, correction, not using the electricity of *three of the turbines.
If you add a power source such as a hot lava to the plan, it might actually work if the water will be evaporated at some point.
Places such as Hawai are ideal for such stuff.
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bethanysh25-yes, that idea came up last year, if only in joke form. I was thinking of UK waters when I had the idea and I don't think we've got anything like that. I suppose a tower could be built on top of an active deep sea volcano and then all the water pumped out. But if we're going to pump water in to make steam then the steam itself could be used to make the electricity. I'll leave that one to the Americans.
//But this time I am using the immense pressure of the deep ocean to move the low pressure water from the bottom of my tower.//

Why will the water at the bottom of the tower be at low pressure? It will be at the same pressure as the water surrounding the tower. If it was at lower pressure (which it won't be, but let's just say it was) it would require even more energy to evacuate the tower because the surrounding water would be at a greater pressure and would be forcing its way in.
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NJ-the water in the shallow reservoir at the bottom of my tower has a column of air above it but the water at the bottom of the ocean has the ocean above it. To push the pistons outward will take some force but I have a geared system of cogs acting as levers that are powered by the energy of the last (non-electric) turbine.
it'd be a lot easier to just use a tidal turbine in places like they do now at scapa flow for example.
Crankfwd, I'd suggest you Google "Electric Mountain'. You're idea is not new but instead of using sea power as you propose, the system is solely located on land and includes a resorvoir.

Dinorwig Power Station, to give it it's proper title is on Llanberis, North Wales. Interestingly, Carol Vorderman played a major part in the design of the roof of the Turbine Hall whilst a young graduate before she became famous elsewhere.

Incidentally, the pumping of the water back to the resorvoir is done deliberately overnight at specially negotiated off peak rates which means that the cost is minimal in comparison to the value of the electricity generated. Without such an arrangement, electricity generation would not be cost effective.

If you're interested in this type of thing, I'd suggest you look at the website:

https//www.gridwatch.templar.co.uk

You need to look at the meter that is called "pumped storage' to see the amount of electricity generated in real time from installations such as Electric Mountain. You'll see that it's minimal in comparison to others but if the investment was there, it could play a major part in electricity generation in the UK. Right now, you can regard it as topping up the electricity needed on the National Grid when required, such as major televised events, when everyone pops out to put the electric kettle on during adverts on the box!


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bigbanana- Hi, yes I've seen this before and although it makes sense from a financial point of view it's not very environmentally friendly. It takes more energy to pump the water back up than the falling water creates, so although the electricity used to do the pumping is cheaper it still has to be taken from the grid which uses other sources of generation i.e. gas, coal, etc
deja vu

Now, if I understand the maths correctly,
You dont understand the maths correctly

Bethany doo dah has got it right - if you add a power source it will 'work' but not generate overall energy

but as someone else said of another crackpot idea
build a prototype and see if it works.

( whittles plan 1929 was prototyped in oo 1941, and yielded 120% predicted. Prototypes usually yield 10-20%. and the RAF assessors were Very Quiet Indeed on the train back to HQ - - realised they had all ignored a war winning idea)
Electric Mountain was also the subject of a OU prog
Science 101 or Tech 101

the one with pgh = 1/2 mv2.... repeats the Newton analysis is an overwheel mill more efficient than the underwheel, and a scientist measuring the temp rise at the bottom of a waterfall 1850 - Thomson I think. So interesting it started me off doing the maff options
oh the OU prog was not - "how to get energy - free !"
but how to store electricity for use later
( clearly there would be a cost to that)
Free energy ? In a village not far from where I live, is a sawmill located by nothing more than a small stream. Attached to his workshop the owner has a 20ft (approx.) waterwheel which generates power not only does this give him enough electricity to work his machines, but sufficient for his house & he says, several other nearby houses in the village.
I'm not sure of the technology - it was explained in a thick Swabian dialect ! - I guess the juice was DC & he has what looks like a large generator & there must be batteries for storage.
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PP- yes, I like Bethany's plan.
I also posted this on Youtube in various comments sections. Someone kindly pointed out that my idea of four generators was pointless as falling water in a sealed pipe is not subject to terminal velocity. So the plan now is just to have one generator at the bottom. I still want to use the ram pumps but think that I should squirt the wastewater upward in a fine spray first and see if I can draw some of the water out with a propellor connected to the cam disc.
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Khandro- Had to look up where Swabia is. Seems I'm terrible at Geography as well as Physics.

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