Generating power through displacement.

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Discussion Overview

The discussion revolves around the feasibility of generating renewable energy through displacement and pressure differences in a submerged cylinder. Participants explore the theoretical and practical implications of energy conversion in this context, particularly focusing on the efficiency of such a system.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant proposes a system where a submerged cylinder displaces water to drive a turbine, questioning if the energy generated would exceed the energy required to remove the water.
  • Another participant asserts that due to the law of conservation of energy, the energy created cannot exceed the energy used, suggesting that in an ideal scenario, the energies would be equal.
  • Several participants argue that in practical applications, the energy output will always be less than the input due to inefficiencies, estimating losses of around 20-30% or even lower based on various efficiency rates of turbines, generators, motors, and pumps.
  • One participant emphasizes that the overall efficiency could be as low as 38% when accounting for multiple stages of energy conversion.

Areas of Agreement / Disagreement

Participants generally agree that the energy output will not exceed the energy input, but there is disagreement on the specific efficiency rates and the extent of energy losses in practical applications.

Contextual Notes

The discussion includes assumptions about ideal conditions versus practical implementations, and the efficiency rates mentioned are dependent on specific technologies and configurations that are not fully detailed.

Mulith
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Hi there.

I've been looking at whether it's possible to create renewable energy though the use of diplacement and taking advantage of pressure differences. Let me explain.

Lets say you had a cylinder 100m x 50m. At the bottom of this cylinder you had multiple inlet pipes. The cylinder is then dragged down into the water using a weight of some kind so as to displace the water. The pressure at that depth, if I'm not mistaken would be 145.304 psi. The water is then allowed to pass through the inlet pipes to drive a turbine which then pumps the water out and over the edge of the cylinder. What I want to know is whether the energy created is likely to be greater than the energy required to remove the water from the cylinder?
 
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I think you may already know the answer to the question: The law of conservation of energy applies.
 
Mulith said:
What I want to know is whether the energy created is likely to be greater than the energy required to remove the water from the cylinder?

No it definitely won't be greater. At the very best, it would be the same if the machine had an efficiency of unity.

CS
 
Energy Can Neither Be Created Nor Destroyed; Can Just Be Transferred From One Form To Another.
This Idea Is An Illusion Like Perpetual Motion Machines.
 
i remember when i used to get out of the box ideas in school and i thought i was a genious ;))
 
Mulith said:
What I want to know is whether the energy created is likely to be greater than the energy required to remove the water from the cylinder?

No. In theory and an idealistic situation, it will be exactly equal. In practice, it will always be less.. less by around 20-30%.
 
It's much, much less than that. You might get a turbine efficiency of 65%, then a generator efficiency of 95%, then a motor efficiency of 95%, then a pump efficiency of 65%. That's an overall efficiency of 38%.
 
russ_watters said:
It's much, much less than that. You might get a turbine efficiency of 65%, then a generator efficiency of 95%, then a motor efficiency of 95%, then a pump efficiency of 65%. That's an overall efficiency of 38%.

oops.. i stated it wrong.. What i was meaning to say is, "Output energy is 20-30% of input work".
 

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