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Open Project to Develop Renewable Energy System
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?
37.62% according to my calculations. But I haven't taken quantum effects into account yet, so I may be slightly off.
Philosophy.
This sounds too good to be true.
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
here's a project using solar heat to drive a ammonia absorption cycle freezer. [PDF]
After looking at the diagram, it is evident the math is not done. A few things come to mind. The most glaring is the wind turbine. Anybody you know of put a turbine in the fireplace flue to get electricity from the heat draft? This is a draft with a large heat change. How much draft do you expect to get from the day/night differential. Don't expect enough juice to power the water pump in a water cooled PC.
r igeration-and-air-conditioning--pid4254146/
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.
The truth shall set you free!
So this relies on a difference in ambient temperatures. You could also drill a hole deep into the ground and send in heat pipes, since it's pretty hot underneath the ground. The issue here is economics, how much power you get out compared to how expensive it is to build the system. Drilling a deep hole probably isn't cheap, and I don't think building a tower is either. At least you don't have to worry about temperature swings underground (sure it could happen, but I'd think air temperature would change more drastically). I think the issue is pretty much based on economics, there are cheaper ways to get energy, and the concept of using ambient temperature isn't new.
just as soon as I get back from the patent office...
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
They cite a mistaken analogy to Linux as one of the reasons they feel their project could succeed, but in fact the problem is that such a system will require capital to run. This in fact makes it the opposite of the situation obtaining with Linux, when one of the key ingredients, low-cost commodity PCs, helped drive and unify development.
Dog is my co-pilot.
And i suppose you think that generating electricity from wind turbines or solar panels is impossible too?
c t
:)
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
Jacko
And i suppose you think that generating electricity from wind turbines or solar panels is impossible too?
I suppose you think it's impossible to turn lead bars into gold?
KFG
This design seems to be a complicated form of utilizing geothermal energy. I don't see any reason why the geothermal energy shouldn't instead simply be used for space heating instead of electricity generation, especially in areas with low levels of geothermal energy availability.
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 efficient.
When considering alternative energy sources, we need to be careful to exploit the most abundant and economically feasible first. In the same way that we did not begin investing in hard to refine oil sands or deepwater oil before we exhausted all the easily available sources of light sweet oil, we should not invest in capital that is designed for diffuse, "use it anywhere" sources of energy before we install windmills in all the major windy mountain ranges and coastal areas, solar panels in all the worlds equatorial deserts, and hydroelectric plants in all the worlds damable rivers.
Doing so would be like buying 2% yeild bonds when 10% yeild bonds with even lesser risk are available.
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.
(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)Natural gold has intrinsic value. Artificial gold is by definition a fiat currency, and henceforth is worth no more than the paper it's printed on.
I will have a sig when the market demands it.
As far as the Zero Emission Solar Panels are concerned, in Germany there is a Zero Emission solar panel factory too, in Freiburg. The trick is that they use Rapeseed oil to power their plant.
"The problem is that I don't see any reason why it shouldn't work..."
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?
Any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so.
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.
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
I prefer the "u" in honour as it seems to be missing these days.
http://cat.inist.fr/?aModele=afficheN&cpsidt=34076 62
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 metals are already present within the wastewater solids before the raw sewage reaches the treatment works. Sludges from industrial areas tend to possess higher precious metal values than those from rural regions. Thus industrial discharges contribute significant quantities of precious metals to municipal wastewaters and sewage sludges. However, elevated precious metal contents in sludges from rural areas show that additional sources are present which remain to be determined by future studies
Liberty freedom are no1, not dicks in suits.
Yes, but as he points out as long as there is a gradient there is energy to be had. The wider the margin, the better the efficency, and possibly you could design in two or three working fluids that can be switched as appropriate? It should be nominally more expensive to introduce a decent vaccume purge cycle to minimize contamination?
-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 has a hells chance (kinda like the EV).
-nB
whois gawk date unzip strip find touch finger mount join nice man top fsck grep eject more yes exit umount sleep dump
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 the most promising renewable sources we are still stuck relying on a supply chain and distrubution network that relies on fossil fuels. So the idea of a transistion to a complete reweable structure is a bit of a pipe dream at the moment and it is unclear weather with exisitng technology it can be carried out at mass scale with a positive EROEI.
perl -e 'print $i=pack(c5, (41*2), sqrt(7056), (unpack(c,H)-2), oct(115), 10);'
Assuming a hot temperature of 70C (black plate in strong sunshine) and a cold temperature of 20C, the theoretical efficiency limit is (343-293) / 343 or 14.6% - assuming a perfectly efficient generator and a very large capacity foe the 85% waste heat capacity.
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.
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former. (Einstein)
I don't know about the part of his design that is above ground.
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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
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.
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.
You might get some "energy capture" efficiency of 100% from solar energy into water - however, keep in mind that any thermal engine is restricted by the Carnot efficiency (1-Tcool/Thot, with temperatures in Kelvin). For a not-so-dangerous temperature differences (using a frozen pond in winter) of freezing-point - to boiling-point (273Kelvin to 373Kelvin), efficiency (max, theoretical, when using a gas) would be about 25%. This is where you start
Photovoltaics have extraordinary efficiency, coupled with zero (close to zero) maintenance. They might cost (both in dollars and environmental impact), but are better than thermal anything in small scale electricity generation
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?
When one person suffers from a delusion, it is called insanity. When many people suffer from a delusion it is called Rel
Drake Landing Solar Community is an example of seasonal thermal storage.
I got real pissed off last year and decided that I am no longer gonna be subjected to
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.
Got Code?
Slashdot ate his mu :)
To be fair, "roll your own" is not pot-smoker slang, it refers to rolling your own tobacco cigarettes in lieu of buying packaged pre-rolled cigs. It's a lot cheaper and sure, could be seen as 'pot chic' to do, but the term's been around about as long as cigarettes have been manufactured.
I'm going to hook up my dog to one of those retractable leashes, and attach that to one of those generators used for the OLPC. Then, when a squarrel runs across the lawn, I'll generate enough electricity to run most of my appliances. Should work, as long as the supply of squarrels doesn't run out.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Wel simply why it doenst work good...
why should warm ground air prefer to go trough a tube to cold areas?
If it simply can bypass it and go from everywhere outside the tube up or down, with less friction. The same goes for the oposite direction.
But no wories there is realy enough energy on this planet....
you only have to dig a hole in the earth, as Lava is quite hot you know, and even without such deep holes, below earth there is enough heat energy stored which make oil and uranium look like a joke. Its only politics of some oil & electric companies who dont want the masses of people to know that. Whenever you go to iceland you see it can be done with not that much engineering (okay their place is ideal, but it can be done everywhere if you have some enginering skills, the start of such projects will cost something but he energy was never for free...) A bit strange we dig a hole from france to england but going down is momre difficult ????
I know you're out there. I can feel you now. I know that you're afraid. You're afraid of us. You're afraid of change.