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I've designed many gear trains for various devices. The reason this is useless is because you can't drive anything with it.

Harmonic Drives have been around a long time. https://en.wikipedia.org/wiki/...

The problem when you couple them together is you get more torque then the teeth can handle.

The reason most gear trains are larger is because you are typically trying to do something useful like taking a small high speed motor and using the gears for a high torque low speed application. This requires large gear teeth to handle the stresses.

http://www.engineersedge.com/g...

This is like a kid building a bridge with Popsicle sticks. Cool but completely useless.

It's called nominal pipe size and you can see wall thicknesses here: http://www.engineersedge.com/p...

The outside diameter remains the same to simplify joining.

Of course it could just have been thin wall tubing or conduit also, but it definitely wasn't "four inch thick" pipe...

As this article (first link when googling for "steam condense efficiency") http://www.engineersedge.com/heat_exchanger/large_steam_condenser.htm mentions, the laws of thermodynamics dictate that the largest temperature difference is the most efficient for mechanisms such as condensation.

The linked article doesn't say that. It states that a large delta T is good for the overall (generating) plant efficiency.

[Better] Citation Needed...

I don't get it. Why does it have to heat the air up ("to produce steam") ??

Why can't it just take the air and cool it down, instead of wasting energy for heating?

It claims to heat the (hot, desert) air to "produce steam" which is then condensed. The water is already in the air, you don't need to heat it, just cool it to grab the water out.

Either this is a crap article, or its one of those over-unity perpetual motion scams.

To everyone questioning the snake-oil of having to steamify this mysterious water vapour before recondensing it, please keep in mind the following:

I. Just because the water molecule is in the air (via most likely evaporation), it does not imply that the water vapor has a lot of kinetic energy (it's not hot water vapor like steam is). An analogous situation to this is how the water vapor coming out of a kettle can cook your hand, but a muggy day only ruins your hair.

II. Next, we want to consider efficiency. As this article (first link when googling for "steam condense efficiency") http://www.engineersedge.com/heat_exchanger/large_steam_condenser.htm mentions, the laws of thermodynamics dictate that the largest temperature difference is the most efficient for mechanisms such as condensation.

III. -Finally, thermodynamics also dictates two last details about generating temperature differences:
1. That it's much more efficient to cool to a temperature close to ambient (same reason why low-TC superconducting magnets are bathed in multiple blankets of cryo-fluids with different boiling points, rather than just liquid helium blanket and room temperature on the other side),
2. That heat is very cheap and easy to make (often referred to as the "dirtiest" form of energy because it's maximized in entropy).

IV. Put all those things together, and one arrives at the following:
-I want to condense water, and to do it well I need a huge temperature difference between the vapor in the air and my condenser coil.
-It's really hard, costly, and wasteful to make a super good air-conditioner inside a turbine for no reason.
-I'll just heat (remember, it's P=IR heating coil easy!) the water first, and then make a mediocre condenser, and get just the same gains as having a phenomenal condenser.

Modern large steam turbines, as used in power plants, typically have an efficiency in the 90%+ range. Thermocouples are well below this (I've seen ratings below 10% for the temperature range of steam/ambient.)

Steam turbines are probably one of the most efficient pieces of technology in the power generation industry. More power is lost in the transmission lines (typically 7.5% per 100 miles) than the steam turbines lose.

Reference: http://www.engineersedge.com/thermodynamics/power_ plant_components.htm

Jacques D'Arsonval (1851-1940) is far better known for designing the analog electrical meter movement (galvanometer) that bears his name. Nearly all DC voltmeters (and ammeters) you are likely to see (well, okay, largely--but not entirely--relegated to museums nowadays) are of the D'Arsonval type.

Aside from the obvious problems with the fact that steel is a lot easier to produce and less expensive than carbon nanotubes right now, that "strength" he's talking about is tensile strength, not compressive or shear strength. (Ref.: here.) Just because something has a large amount of tensile strength doesn't mean you'd want to build a building out of it.

In fact I'm fairly certain that there are types of plastic (nylon maybe) which when woven together have more tensile strength per unit mass and volume than a comparable amount of steel, and I'm looking out my window right now and don't see any plastic-framed skyscraper buildings.

Yes it does. My point is that resistance to corrosion is not your primary concern when making tools. This is a marketing ploy. This is why many tools are made from tool steel (http://www.engineersedge.com/tool_steel.htm). You'll notice that some of these are very common knife steels (among custom knifemakers). 304 is not. Didn't stop the military from using carbon steel for the venerable Ka-bar knife. You can blue carbon steel also. And let's stop calling it INOX, because it's pretty ovbious they call it that to distract you from the fact that's it's just Stainless Steel. Let's call it "Wham" instead. Wham-L will be the low-carbon version more resistant to chromium carbide precipitation at the grain boundaries during prolonged exposure to high-temperatures.

The 250% heat output sounds like a good thing

From a research standpoint, yes. Without regard to whether or not the ultimate cause of this energy release turns out to be fusion, the ability to get more energy out of a system than you put in is A Good Thing (for people looking for sources of energy anyways).

From the POV of "free energy for everyone!", it's no more than mildly interesting. To get electricity from heat, you need to go through a Carnot Cyle (real ones run about 34% efficient, IIRC) and an electrical generator (about 90% efficient, IIRC). Multiply those two efficiency and take the reciprical and it turns out you need a Cold Fusion process that produces 3.27 times (327%) the energy that you put into it just to run itself. Then factor in the overhead of running the plant, the cost of the plant itself, and a large enough profit margin for someone to bother laying out the initial funding to build the thing in the first place.

So, you need to increase the power output of the process to output 500x the input power (or more!) in order to make it feasible as an energy source. Presuming, of course, that it's even scalable enough to be used in a power plant. It might not be possible at all and, if it is possible, it'll be a few decades before you see the first one. Factor in the cost of Deuterium and it might not be any cheaper than current energy sources.

While sites like Engineers Edge are great for companies like Deltec Company it is nice to know there is development in software resource solutions.