Stirling + Heatpump = Free Energy?

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generalpost
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First Name: Bryan
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Stirling + Heatpump = Free Energy?

Post by generalpost »

Would it be possible to use a Stirling to drive a heat pump
compressor as actual work and using the "hot side" of the heat pump
as a method to sustain the engine? Cold side as well? I realize
this sounds dangerously close to the rediculous notion of a
perpetual motion/free energy device but, I am curious if the amount
of work required to "move" ambient heat in the HP would outweigh the
amount of work the Stirling could generate from this looped
exchange. I speculate if it were to work at all the entire system
would have to be primed to allow the heatpump to attain temp
differentials. This would obviously be impossible with any type of
looped electrothermic heat production due to loss but, I'm
suggesting using extracted ambient heat from the air (in effect a
form of solar energy) in a most efficient manner. Any of you
engineer types care to comment?
stan.hornbaker
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Stirling + Heatpump = Free Energy?

Post by stan.hornbaker »

Speculate no more.
Lets understand exactly what your are proposing.

1. Set up a Stirling engine to drive a heat pump.

2. Use the heat rejected from the heat pump to provide the heat energy to drive the Stirling engine which drives the heat pump which ....

3. The output of each device deceases over time, a very short time, and entropy increase.
Obviously this would be a PM device/system, IF it worked, which it cannot!

Any time heat/energy is transformed by a real device a portion is converted to a useful form and the rest must be rejected to the enviornment.
Now if you could just extract energy from the vacuum, ala Tom Bearden you could run the assembly barkwards and ...

OH! but if you could extract energy in that manner you wouldn't need a SE or a HP.
alan___9552
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Response to Stirling + Heatpump = Free Energy?

Post by alan___9552 »

William, I dont think Bryan was suggesting that the enery was being 'extracted from a vacuum' but did inidcate that the energy was to be extracted from the ambient air 'in effect a form of solar energy'.

The problem as I see it is not one of PM or ZPE etc but of engine/compressor efficiencies and the actual temperatures involved. Some _really_ rough guestimates that I would imagine to be within an order of magnitude of their mark;

Assume a carnot cycle heat pump using a conventional working gas and a reciprocating compressor the C.O.P (coefficient of performance = Ein/Emoved) in a 'high suction pressure application' with a capacity in the order of 10s of KW should easily be 5:1, ie for every KW power applied to the compressor 5 KW of heat energy is 'moved' from the 'cold' side (including heat of compression) to the 'hot' side. The kicker is that to obtain such an attractive C.O.P. the cold side of a 'high suction temperature application' is around 280K while the bulk of the (latent heat - i.e. at constant temperature) energy rejected from the 'hot' side would be around 330K. The maximum temperature on the 'hot' side, at the compressor discharge, may be another 50K higher but it is only due to a limited amount of sensible heat. So the effective td for the lions share of the heat being moved by the heat pump is only in the order of 50K

If the heat pump is redesigned to have a lower 'cold' side temperature , like in a typical foodstuff freezer, to 240K the C.O.P. takes a dive (1.2:1, if you're lucky). Likewise, attempting to raise the 'hot' side temperature has a similar effect - without considering the effect of higher discharged temperatures on the compressor lubricating oil. Using different gas/materials will still result in the same trends.

The 'break even' point here would be to have a C.O.P. for the HP that is greater that the reciprical of the efficiency of the SE. For a C.O.P. of 5:1 with Tc=280K and Th=330K are we going to get >20% (1/5) efficiency out of a SE (1-Tc/Th) ?

Something to note about the carnot efficency, for high temperatures (where both Tc and Th are 'large') the same td will yeild lower efficencies than for lower temperatures. ie;

td = 50K, Tc=950K and Th=1000K
1-(950/1000) = 0.05 or 5%

td = 50K, Tc=230K and Th=280K
1-(280/330) = 0.15 or 15%

Not an engineer, but a refrigeration/airconditioning mechanic in a past life...
pranabjyoti_calcutta
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Response to Stirling + Heatpump = Free Energy?

Post by pranabjyoti_calcutta »

I, Pranab Jyoti Ghosh, am an Indian physics graduate and myself have theoretically developed a technology on producing energy without any kind of fuel. This technology is a combination of processes that are well tested and now in use in different industries and research projects. I have done everything that I can do by myself. But for further advance, I need financial and technical assistance. I am assuring you that this project is just need to be made and improved. All the basic experiments had been already done successfully and enough data had been gathered. In short, it is a new and exciting kind of technology and as far as I know, nothing like this exists this day. Can you help me to make my idea a reality? I am giving below a brief description of my technology.
This project is aimed at producing electricity by using the vast heat content of atmosphere. The scheme is basically aimed as producing electricity by extracting heat from atmosphere. In this project, this is done by using mechanical arrangement similar to heat pump. This system is used to squeeze energy from huge volumes of air and to produce temperature difference by which energy can be produced. It is to be noted that fresh water and salt are added bonus to this project, as salty brackish water can be used in this project. This is done by vaporizing water inside an enclosed container named “Evaporator” with the help of a vacuum pump. As the vacuum pump sucks air from the container, the water inside began to evaporate and in this process collects its latent heat of vaporization from water. For that reason, the water inside becomes colder and heat began to flow in from outside. Thus in effect, the latent heat of vaporization of water is collected from outside atmosphere. In the open-cycle OTEC, vapor is produced in the same manner and on experiment it was found that to have vapor flow rate of 1 kg/sec, power needed at the vacuum pump is 3 KW. Whereas, the latent heat embedded in 1 kg of vapor is 2.31 MW. After the vapor is produced, it is heated further with adiabatically compressed, hot air. After heating the vapor in the Boiler, the hot, compressed air is passed through the Evaporator to give up its residue heat to the water inside. The process is the same as that of common heat pumps sold in the market. And finally, the temp. diff. between the Boiler and the Condenser is created by suddenly releasing the compressed air at the Condenser. And thus a system of real efficiency of >50% is created.
My Whereabouts:
Name: Pranab Jyoti Ghosh
Address: 153/10/C, S.N.Roy Rd., Kol – 38, West Bengal, India
Telephone: 91-33-24037734
E-Mail: pranabjyoti_calcutta@rediffmail.com
fvanicek
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Response to Stirling + Heatpump = Free Energy?

Post by fvanicek »

The idea od using heat pump and heat engine in closed loop is obviously no-go. But-yes, open loop, basically sucking up energy from ambient air, inputing at temperature x and exhaling it at lower temp, that might work if only we could sort out the efficiencies. If the "efficiency" (COP) of the heat pump were even a little bit bigger than of the engine, such open loop would work!
stinger
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Response to Stirling + Heatpump = Free Energy?

Post by stinger »

If the COP of the refrigration system is 4:1 and many are more effieciant than that depending on the ambient temp it will put enough power in to a Stirling engine to operate the Refrigration system. The problem would be that as I understand it Stirling ned a high delta T so the hot side of the refrigeration system would have to be 300F or more and most are about 130 -150F. Valving and some sort of azeotropic refrigerant could boost pressure and temperaturebut I am not sure if a compressor could hadle the stress.

Putting a Stiring on the hot side would make the system more efficient lowering the head pressure or perhaps and therfore the load on the compressor motor.

I suppose a Stirling on the hot side of a large system could turn a generator shaft and that electricity could be used somewhere.

Let's say 30K BTUs goes into the Stirling from the fridge's condenser coil. Let's say the the Stirlin is 30% efficient at a low delta T. Let's say the compreesor is a 2 HP compressor. I don;t feel like doing the conversion from BTUs to Watts to HP right now but if the fridge/heatpump had a high COP the Stirling will produce quite a bit of mechanical energy.

Another thing the Stirling could do is run a blower fan and because the velocity would change with the temperature of the refrigerant it would eliminate the need for fan cycling of a head master valve.
e,reitsma3
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Response to Stirling + Heatpump = Free Energy?

Post by e,reitsma3 »

Hello.
I'm no engineer, but i've been thinking about this for a year or so, and i think its very well possible to use a heat pump to drive a Stirling engine and use the electricity provided by an electic generator(hooked up to a battery) driven by the Stirling engine, to power the heat pump. I think you would end up with heat,electrical or kinetic energy to spare.
Much to my suprise, about a month ago, this idea was patented by a frenchman named Baron Denis Philippe.
You can find his patend here: http://v3.espacenet.com/textdoc?DB=EPOD ... 2007101919
Very interesting.

Erik Reitsma, drachten, Netherlands.
stan.hornbaker
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Response to Stirling + Heatpump = Free Energy?

Post by stan.hornbaker »

# Alan van den Bosch, July 28, 2005 "William, I dont think Bryan was suggesting that the enery was being 'extracted from a vacuum' but did inidcate that the energy was to be extracted from the ambient air 'in effect a form of solar energy'."

The ambient air can only supply heat to the Stirling at the ambient air temperature. A Stirling engine must have an input temperature on the order of 1500-2000 deg.F to produce useful output and there must also be sufficient heat (BTU's etc.) to be converted to mechanical output.

# erik reitsma, October 15, 2007 suggested that the Patent issued to Baron Denis Philippe would accomplish his idea, "i think its very well possible to use a heat pump to drive a Stirling engine and use the electricity provided by an electic generator(hooked up to a battery) driven by the Stirling engine, to power the heat pump."

Two Comments: First a Patent is nothing but an expensive piece of paper and does NOT guarantee the the patent is viable, i.e. work as patented.
Second here again the proposal is to cascade two or more devices into a system to acheive the impossible.

The more devices or machines involved in a proposed system the worse the resulting performance.
arnoldlaine
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Response to Stirling + Heatpump = Free Energy?

Post by arnoldlaine »

The idea that the system would slowly produce less and less is a fallacy caused by lack of technical knowledge.
The system would be unstable without the use of a regulator. However regulators are nothing new and very easy to design.
The system without a regulator would either increase continually in output or decrease continually. The system would go into a state known as "run away".
The regulator would sense that the output was dropping and feed more proportion of the output of the heat pump to the Stirling engine and thus the output would increase again. At some point the output would start rising above the desired value and again the regulator would step in and reduce the proportion of heat from the heat pump going to the Stirling engine thus reducing the output to the desired level again.

The system proposed is entirely workable and would provide "Free Energy" from the environment until the end of the World as we know it.
The Oil companies do not want you to know this and so post disinformation about free energy.
bptdude___2569
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Response to Stirling + Heatpump = Free Energy?

Post by bptdude___2569 »


I am probably one of the biggest fans of saving the world with a clever machine.

Heat pumps work, as far as a nice chiller, if your dad owns the construction company and lets you use the heavy equipment for free, you can build a house with reduced air conditioning bill in places it is very warm.

If I lived with hot rocks under my yard, so hot, steam comes out of vents nearby, I would be so made! :) This is like living with a waterfall in your yard, though most people just do not picture heat as a source of power, like they do a waterfall.

If there was some source to create the vacuum, something there anyways, that is a by-product or unused find of nature, then you have your clever way to produce power, and the Stirling may be the correct conversion device.

I am not able to crunch the numbers, but experience has taught me, the means to vacuum, the vacuum that releases the energy, will take more, even if slightly, than the amount of energy that can be extracted from the vacuum's reaction to water.

That is where I would focus for the problem of why this will not work.

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