Recycled Energy versus Renewable Energy

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TMT
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To days trend topic is “Renewable Energy”. Everybody are trying to jump in this topic wagon. They are discussing either wind or solar farm is better choice for future investment. They also arguing their solution will prevent global warming. But, in my opinion (especially wind farms) will yield more serious problems in feature. We know that those wind farms will block or slow down the wind (the speedy air flow). Atmosphere will compensate this action by creating new air flow path. But previous flow path will be destroyed. The effect of this flow is also destroyed.

Think about a wind on Sahara Desert. It blows out the dust and create Sandstorm. Then those dust be carried to ocean. Because of nutritious content of dust, algae, seaweed, planktons grow are accelerated. Then, other living creatures nourished with, grow in population and support food chain. Eventually humankind will be benefited from this chain and hunger problem may get remedy. If the wind blocked or slowed down, those scenarios will not be happened.

Again, wind help to carry pollens, seeds from place to places. If you block or slow down the wind plants will not be spread freely on earth surface. Briefly you may alter echo system in adverse direction.

I couldn’t visualize solar farms adverse effect in advance. But there is heat change in soil (ground) structure?

And, we should see those attempts just reduce fossil fuel consumption only very few. Global warming will have influenced only very few.

If we develop a technology to recycle energy of used one (environment heat energy) to a usable one (electricity), we will end energy request forever also stop Global warming immediately (since energy extraction from environment will cool it down).

Is such a technology can being developable? According to me YES!

Let’s look in our knowledge bag. We need work power to produce electricity. (positive displacement power, or kinetic energy). To produce work power, we need energy. We have abundant free energy in environment as heat form. If we look pattern for energy-work couple, we will see all stored (chemical energy) in fuel converted to heat energy in first step, expansion of a fluid (volume growth) with produced heat in second step and work done with positive displacement in final step.

Can’t we use environment heat for this process? No! since environment heat is not in value to produce pressurized fluid. Ok. If you choose fluid as water (a classical fluid, cheap and abundant) this argument is correct. But if you choose fluid from organic fluids answer converted to yes. Take Butane for instance, it boils at 40C and produce considerable pressure at room temperature.

You may say this pressure is not sufficient to produce enough pressure to operate a machine to produce quality work power.

If you consider a heat pump, you may rise the temperature more above the room temperature. 800C is quite possible with any ordinary heat pump (commercial air conditioner). The pressure with this temperature in butane is around 13 Bar which is quite good to produce work through good designed turbine. (suggested turbine must operate in closed organic Rankine cycle since we can’t dispose working fluid (butane))

I’m expecting another question “energy is used in heat pump. Is it efficient?” YES. We are talking about two engines cascaded to each other. A heat pump creating a heat reservoir, and a heat engine produce work using this heat reservoir. Efficiency calculation is multiplication of both machine efficiency.

The heat engines efficiency calculated by Carnot formula using heat values (Temperatures of Source (Hot) and Sink (Cold)) which is 1- Tc/Th and reverse heat engine (heat pump) Th/(Th-Tc)

For Heat pump:

The hot temperature selected as 800C (353.150K) (which is achievable by commercially available heat pumps) The Cold temperature selected as environment heat is 400C (313.150K)

For Rankine Turbine:

Cold temperature selected as below the temperature of sublimation temperature of selected working fluid butane in our case (< 40C) assume -150C (258.150K)


Heat pump =>>> Th/(Th-Tc) = 353.15/(353.15-313.15)=353.15/40=8.829

Saying with 1Kw energy we can transfer 8.829Kw energy from 400C environment to 800C environment

Turbine =>>>> (Th-Tc)/Th =(353.15-258.15)/ 353.15=95/353.15=0.269

The maximum efficiency of turbine according to Carnot theorem.

Final 0.269*8.829 =2.375 saying suggested system produce 2.375 Kw energy per 1 Kw energy

The capacity of heat pump 8.83-kilowatt hour = 30 129.209 267 Btu

With 30K Btu capacity heat pump (using 1Kw energy input) we can convert 8.83Kw energy to electricity in 1 hour.

If we use 1Kw of this converted energy for heat pump operation, we will convert 7.83 Kw can be usable. And environment heat reduced 28.188 Kilojoule

We should focus on a good tribune and generator design and select an organic fluid with high pressure gradient @ heat pump outlet temperature (800C)
 
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  • #2
CWatters
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It's all very well using environmental heat to evaporate butane but you also need to condense it again.

I think some research has been done on exploiting the temperature difference between the sea surface and at depth but I don't think it's very practical.

edit: Google found..
http://www.oceanenergycouncil.com/ocean-energy/otec-energy/
 
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  • #3
TMT
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I defined turbine as Rankine type. Condenser pump is standard in this type turbines. Also we have heat pump in our configuration. We can harvest heat from turbine container first. The turbine exhaust the butane vapour into very cold environment yield condensation then standard condensation pump will convert the vapor to liquid. No gap.
 
  • #4
CWatters
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Any chance of a block diagram? I'm not sure how this can possibly work.
 
  • #5
russ_watters
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This is an attempted perpetual motion machine, which is a violation of the laws of thermodynamics and PF rules, so this thread is locked.

FYI, though, the flaw is that you are showing that you get the low temperature butane for free and haven't included it in the heat pump efficiency calculation, which you need to to generate it.
 
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