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Open Project to Develop Renewable Energy System
Posted by
Zonk
on Mon Jan 08, 2007 02:33 AM
from the sounds-very-sciency dept.
from the sounds-very-sciency dept.
rohar writes "We have been working on a system that combines some existing indirect solar technologies to build a location independent, renewable, reliable and economically feasible indirect solar electrical power generation system. The idea is to 'roll-your-own' geothermal source by capturing heat from the ambient air with a solar powered absorption heat pump, store it underground and generate electricity from the air cooling convection. When the air is cooler the stored heat is then used in a reverse process to generate electricity by transferring the heat back to the air when it is cooler (at night or seasonal). There are many additional benefits including clean water capture from the "dehumidifier" effect of the air cooling, construction from common materials and thermal storage that may be incorporated into dwelling heat systems." After reading over their description, how likely do you think it is to work?
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How Likely? (Score:5, Funny)
something interesting I saw a while back... (Score:3, Insightful)
Wind turbine (Score:5, Informative)
Getting the heat to provide the high pressure ammonia to feed the expansion valve is also a problem. Time to do the math.
A good place to start is Modern Refrigeration and Air Conditioning.
http://www.bizrate.com/technologybooks/modern-ref
Instead of trying to get high pressure ammonia, look up continious cycle absorption cycle refrigeration. The key is using vapor pressure to your advantage. Day/night cycles are not going to provide the requried amount of pressurised liquid ammonia for the job.
Study and learn continious cycle absorption cycle refrigeration then redesign and eliminate the expansion valve, & turbine. Add a light weight inhert gas to the entire system to make distilation of ammonia possible and stop uncontrolled reasorption into water.
Re: (Score:3, Interesting)
OK - I have not read the article but I will point out that a century old kerosene refrigerator uses a wick and not a great deal of fuel plus a bucked of water to handle expansion and condensation. Solar thermal has potential and scales up - things will be practical given a large enough size, and practical things become smaller given a larger heat differential.
Re:Wind turbine (Score:4, Informative)
Early kerosene refrigerators used a single cycle sytem where the ammonia boiled or evaporated as it was absorbed into water. To get the ammonia back and the water, the cold side was stuck in the bucket of water and the room temprature water chamber was heated by the kerosene flame to seperate the ammonia from the water. Do a Google search on "iceballs ammonia" for a version that still entertain people today who build their own.
Before you build your own, remember this runs on high pressure during regeneration, and uses ammonia, a relatively hazardous material.
http://www.ggw.org/~cac/IcyBall/crosley_icyball.h
Simple day/night tempratures will not complete the regeneration cycle. The temprature is too low. Even though very little kerosene is burned in those refrigerators, the burning kerosene did provide the required tempratures to complete the regeneration cycle.
Parent
So... (Score:4, Insightful)
Re: (Score:2, Informative)
As for production of energy if they wanted to not store it then ground/air temperature difference during the day would probably be similar to day/night air temperature difference.
Re: (Score:2, Informative)
http://www.swissinfo.org/eng/front/detail/Geother
I'll let you know... (Score:4, Funny)
The analogy to Linux (Score:4, Insightful)
Geothermal.. (Score:2, Insightful)
In areas such as Iceland or Hawaii, this technique would be more feasible, but simply using the more abundant geothermal energy sources to drive steam turbines without the use of refrigerants or air turbines would probably be more e
For this, hell no. (Score:2)
Perpetual motion (Score:2)
might work with large heat differences (Score:2)
This might work in some places where there is a large difference in temperature from day to night. Where I am living on the edge of the Saharah desert we have hot temperatures all year around but the temperature does drop considerably at night. However, the places like this that have such differences generally need the electricity during the day for cooling rather than at night for heating. So the system would need a good way of storing the energy for day time use and I am not sure of the best way of doing
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The spanish organisation built one, and it worked for at least 7 year to my certain knowled
Re:might work with large heat differences --- (Score:2)
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You dont really need that much of a temperature difference to generate electricity; there are model stirling engines that work off the difference between the heat of the air and the heat of your hand.
Of course, you still do need enough of a total stored energy diffrential to actually generate the electricity needed, so at low diffrentials you may need larger initial storage generators or storage volume.
What a fazinating idea (Score:4, Interesting)
It may be that this particular case will not work, but the idea is great. Roll it yourself systems developed, improved, forked and tested online through an open source ideology... great stuff (: One has to admire the potential social consequences of the open source ideas, both in technology, law and governance.
Sadly for some, this also applies to warfare [typepad.com].
(this blog speaks of, amongst other things, how "open source warfare" (OSW) is the key behind the insurgency success in Iraq. The methods applied by what is essentially guerilla groups testing wildly different approaches across the nation, then learning from their success, contrary to a carefully planned and centralized military system)Re: (Score:2)
That seems like the likely outcome.
Hmm. Perhaps they should consider putting the design under a wiki which specifically encourages original research, and see what happens to it.
When all you have is a hammer.... (Score:5, Insightful)
Not very likely at all - because the creator doesn't really have any idea how steam engines, or refrigerators work. Also, like most armchair engineers he's really, really light on the math.
I find this part particularly amusing;
I think the creator quite misundertands how F/OSS works - he somehow thinks that people who aren't programmers get together and somehow create the programs, and that the same magic wand will work for making this kludge a reality.
Then he makes laughable statements like this:
I guess in his world structures and machinery aren't subject to wear and tear - but here in the real world they are.
Re: (Score:2, Insightful)
The miracle of modern technology is that consumer grade stuff just works, with very little extra input required. I'd submit that is why someone can seriously suggest such a project without factoring in maintenance.
Other than a car, I can't really think of many consumer grade pieces of 'equipment' (which people regularly interact with) that require regular maintenance.
Even newer cars don't requ
On the right track... (Score:2)
Re: (Score:2, Interesting)
Photovoltaics have extraordinary efficien
Rough efficiency (Score:3, Informative)
At night, it's going to be more like 30C -> 0C which is down at 9.9% efficiency.
Even cheap solar cells do better than that, you'd be better off just buying solar cells.
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ethanol and biodiesel. (Score:2)
This has nothing to do with their method, but I think that claim is a bit misleading. From the wikipedia article on ethanol:
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With ethanol being produced in such large quantities, such as in Brazil, I don't understand how this is subject to debate.
The debate being that working on a Sugar plantation producing ethanol, like where I am working, we can produce Ethanol with a positive ERORI.....BUT, there is so much of the infrastructure, resources, supply chain and distribution network that still relies on fossil fuels that the whole measurement of the EROEI is a bit misleading. Yes, we have a positive ERORI while we have fossil f
bought a corn stove (Score:3, Informative)
swings in the fuel market. I bought a corn stove and installed it, best thing I ever did, so far
this year heat has cost me less than 1/3 of what it normally does. Much simpler system than what is described here, corn in and heat out. My stove is also multi fuel if corn goes high I can buy wood pellets, barley, cherry pits etc whatever is running the cheapest.
Here's an idea (Score:4, Funny)
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The problem is that I don't see any reason why it shouldn't work; and there are plenty of people who don't understand that just because something works doesn't mean it's not too good to be true as well.
KFG
Re: (Score:3, Insightful)
Think harder. The logic seems to be that we pump ambient heat from the air into the ground... which is where things seem to fall apart. For example, just how MUCH heat can we gather and store in the ground? What's the differential? How much can we get back?
More to the point, how do we keep the heat we pump into a point in the ground from radiating away and disapating?
It is a solved problem (Score:4, Informative)
The underground bit however, works well in practice, at least in the Swedish climate.
Extracting heat from a temperature differential with a heat pump and storing it in the ground, is in wide commercial use here, and you can save money on it.
In a quick search in the Swedish yellow pages, I found hundreds of contractors to choose from.
There has also been plenty of research conducted in this field in various Swedish universities. The article author would probably save himself a lot of time if he looked some of it up. Here are a couple of abstracts (in English and Swedish):
http://www.lib.kth.se/main/stems_projektrapporter
Parent
Re:hmmm (Score:4, Informative)
Effectively speaking, you can't store heat in the ground. If you could, then heat pumps today wouldn't work. And plumbing in the north would fail every year. The ground temperature much below 3-6 feet stays a relatively constant temparature all year round. I think between February and August it might vary 10F if that.
The point being that if it takes 6 months of weather on the surface to effect a 10F change in the ground, you won't be able to create a heat pump powerful enough to make this project work. The earth has the property of being a massive heat sink with a reasonable thermal conductivity. This allows heat pumps to pull heat out of the ground in winter and push it into your house. They become inefficient at very low temperatures because the heat transfer freons don't work very well, not because the ground runs out of heat.
It might be more possible to do this if you had an insulated/isolated storage of water and used that as the heat source for storage and retrieval. You could also do it with air and stone. But in every case, you have to provide a means of thermal isolation between the earth and the storage facility. Also, it would be far more efficient to store the heat by means of thermal exchange pipes (solar heated pools) than trying to pump the heat into place.
The convection tower concept isn't new. I think someone came up with that in Australia about five years back. But the storage of heat for later retrieval is.
Parent
Re: (Score:3, Informative)
Re:Thin Air (Score:4, Insightful)
Generating electricity from a heat difference is entirely possible, its just a matter of how efficient the whole process is as to whether its worth it. Actually if your after more information on that (it works both ways too!), then have a read here: http://en.wikipedia.org/wiki/Peltier-Seebeck_effe
And the water thing is just a by-product http://en.wikipedia.org/wiki/Condensation [wikipedia.org]
Jacko
Parent
Re: (Score:2, Funny)
I suppose you think it's impossible to turn lead bars into gold?
KFG
Re: (Score:2)
-nB
Re: (Score:3, Funny)
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Point I was making is that once it costs less than gold to make gold, then the market for gold (as currency
Re:Thin Air (Score:4, Insightful)
And I think the point KFG was making was a parallel one, that alternative sources of energy, right now, net so little gain in comparison to the fossils fuels that there's little point. And when the fossil foils become horribly expensive unfortunately so will all the the alternatives, since producing and maintaining them depends on a rather nontrivial amount of fossil fuels. It's easy for people to shrug off fossils fuels as just another energy source but really, think about what they are... millions of years of condensed, stored, solar energy, with a dash of geothermal thrown in too. And we're burning through that million years of energy in decades. When the oil is gone, I think our descendants (assuming any survive the bloody resources wars) are going to be absolutely furious with us that we just burned the stuff.
Parent
Re: (Score:2, Funny)
Hmmm... think air...think air... *SNAP* Hey, Al gore invented the Internet and is all about green energy, maybe I should think like him. Here goes:
With Global Warming, we've got a lot of extra heat in the air - meaning that the atmosphere is both warmer and wetter than would be before we stared using energy stored in hydrocarbons to power our economy and release all the trapped CO2 back into the air. On first glance the method in the a
Gold from human shit. (Score:3, Interesting)
Sewage sludges from German municipal wastewater treatment plants possess high gold concentrations (280 to 56,000 g/kg in dry matter) similar to some ore deposits which are being mined for gold. In addition, the sludges exhibit elevated platinum (10 to 1,070 g/kg) and palladium values (38 to 4,700 g/kg), and low osmium (3 to 51 g/kg), iridium (0.6 to 26.5 g/kg), ruthenium (2 to 390 g/kg), and rhodium contents (2 to 352 g/kg Major amounts of these metal
Re:Gold from human shit - numbers are off? (Score:3, Funny)
So, in units people feel comfortable with, there's at least half a pound of gold in two pounds of shit? And under favorable circumstances, shit is 5600% gold? Something smells around here, and it's not fishy.
Micrograms, perhaps?
Re: (Score:3, Insightful)
Re: (Score:2)
In Germany there are several different projects and ways found to build a 'zero emission' house.
I don't think that it is fair to say there is such thing as a 'zero emission' house. Most of the equipment used in such houses such as turbines, solar panels etc are all built in factories and from materials extracted and manufacturered from processes that are using fossil fuels.
In fact, most of the green fuels we have today are in fact products of fossil fuel because their supply chains rely on fossil fuels
Re: (Score:3, Interesting)
Re: (Score:3, Interesting)
Well that sounds like a nice project, but still far from a 'zero' claim due to the supply chain issue. All this says is that the first level of the supply chain e.g. he panel factory uses a renewable source. However, at the end of the day the supply chain is still heavily relying on fossil fuels for agricutural equipment, distrubition, raw material extraction and other equipments and proceses.
Anyway my point is not to be argumentative about the definition of 'zero' but rather to highlight that even with t
Not Yet. (Score:3, Informative)
At this time, Solar provides the least amount of energy of all of the alternative systems. Hydro, wind, geothermal, and methane generation currently provide more energy than does solar. In addition, they do it cheaper.
But long term, homes will probably be better off using a geothermal heating/cooling combined with electricity from pv systems
Re: (Score:3, Insightful)
-nB
All I know is that I applaud his making it "free". Likely if he had tried to make money off of this tech it would fail, but now enough tinkerers may pick it up that it ha
Re: (Score:2)
Why? Do you have any data?
Or do you support the Victorian concept that the mill owner should own everything? Or maybe the communist idea that the state should own everything? Or the Italian idea that the Mafia should own everything? (Just kidding ;-}