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?

Comments

How Likely?

[Umbral Blot]

37.62% according to my calculations. But I haven't taken quantum effects into account yet, so I may be slightly off.

Wind turbine

[Technician]

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.

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-refr igeration-and-air-conditioning--pid4254146/

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:Wind turbine

[Technician]

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.

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.ht ml

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.

So...

[CookieOfFortune]

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.

I'll let you know...

[advocate_one]

just as soon as I get back from the patent office...

The analogy to Linux

[Scareduck]

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.

Re:Thin Air

[Anonymous Coward]

And i suppose you think that generating electricity from wind turbines or solar panels is impossible too?

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_effec t

And the water thing is just a by-product http://en.wikipedia.org/wiki/Condensation :)

Jacko

What a fazinating idea

[Knutsi]

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)

Re:Thin Air

[yada21]

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.

Re:Things like that do exist

[Anonymous Coward]

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.

When all you have is a hammer....

[DerekLyons]

After reading over their description, how likely do you think it is to work?

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;
 

2. The principles and project management of Linus Torvolds with Linux and the many other contributors to Open Source and Free Software has shown such success with large projects.

3. There are many people with good ideas and a willingness to help, but Mechanical and Electrical Engineering and Physics are not their field. The project is based on bringing people together to work on something that has benefit for everyone.

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:
 

In the capital investment for energy sources that are renewable, the capital investment is not important. Once the system is built and producing electrical power, it doesn't run out.

I guess in his world structures and machinery aren't subject to wear and tear - but here in the real world they are.

It is a solved problem

[IMustBeNewHere]

I don't know about the part of his design that is above ground.

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. asp?subj=vp

Re:Thin Air

[Anonymous Coward]

Point I was making is that once it costs less than gold to make gold, then the market for gold (as currency) will be broken.

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.

Re:hmmm

[tacocat]

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.

Here's an idea

[SnarfQuest]

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.