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CHALLENGE 60% efficient solar build Answered

I would really love to see this Instructable be done but i don't have the technical background or resources to do so. It seems like a pretty easy build and looks like it can be done with common items. If the project is done correctly it should be a very powerful source of energy for free. It converts solar energy at 60% efficiency which is almost twice as much as current solar panels. It works by converting solar heat into electricity by heating hydride (which is hard to find but i think it can be replaced with a refridgerant) into a gas, which generates pressure to run a motor which runs a generator producing electricity and then the gas is converted back into the liquid state. The project will replicate
Solar Powered Electric Generator

Please contribute the time to building this it will pay off tons.
Thanks To Everyone Who Helps.



10 years ago

Hmm. It looks like a pretty conventional "heat engine" with an unconventional storage mechanism for the working fluid (hydrides storing hyrdogen.) Very similar to a steam engine, in fact... That means it has a max possible efficiency of something like 30% assuming 0C/100C temperature differential (1-Tc/Th), plus all the usual problems with heat engines (ie, keeping the cool side 'cool')


10 years ago

Heh. Well, so far this qualifies as the best source of info I can find on the company, which appears to all come from the Ergenics web site, and as a wiki might have been placed there by the company. In any case, you don't want to step in what I'm smelling.

The compressor works by, first, absorbing hydrogen gas directly into a metal material, thus forming an alloy of the metal and hydrogen called a "metal hydride".
Puh-lease. An alloy is something different. Hydrogen gas can be hard to work with as it will leak right thru practically anything. Many things will absorb hydrogen like a sponge absorbs water. While "hydride" is such a nebulous term that even water can chemically be considered a hydride, what is referred to for hydrogen storage is an interstitial hydride. Basically, metal atoms arrange themselves in a 3-D lattice formation, a continuous structure, and the hydrogen slips into the spaces between the metal atoms. By heat and other processes the hydrogen is "coaxed" out of the lattice for use.

But letting metal soak up hydrogen is not creating an alloy. All you may be creating is hydrogen embrittlement which generally ain't helpful for anything. And this is supposed to be a permanently sealed system using hydrogen? Lone hydrogen atoms are tough to contain, H2 only slightly less so, and if they can go into metal then they can go thru metal, and those "heat exchangers" sure look like metal. The hydrogen will eventually dissipate into the open air, and then...?

I'll tell you what you're likely looking at in the video. Notice you're not seeing any containers of "hydride" being dunked in the water, but you are seeing what looks a lot like many many feet of copper tubing all wrapped up. Tubing which is of course hollow, can contain air, and for that length of it a lot of air. And since it has such a large contact area since so much tubing was used, there would be a great deal of rather fast heat transfer, resulting in a rapid expansion of the air if one was was dunked in hot water, and rapid contraction with cold water. On the setup shown, that would yield enough of a pressure differential to drive that small motor-generator set. Of course the pressure difference gets too low to drive it after awhile, then that's when they flipped it over.

Something else that's just don't seem right about the write-up, they say that's a hydraulic motor-generator set. Hydraulics involves liquids at high pressures, often very high, several thousand psi. This is clearly an application for a pneumatic motor, pressurized gas. The possibility that a competent engineer approved that write-up approaches zero.

Summary, you're looking at a lot of hot air moving about. And some cold.

On the upside, you probably can replicate it yourself. Just takes the wrapping up and soldering of lots of copper tubing, an air powered motor like perhaps a small grinder (Lowes etc), 12V permanent magnet hobby motor (acting as generator when driven), spotlight, and putting it all together. The air tool would need an exhaust port that's threaded, like those that take those small metal sound muffler-things (ack, what are they called?!), for a return line to keep the system sealed. Offhand I don't know if they would run backwards if the pressure comes in at the exhaust port, if not some valving would be involved for when you flip it between buckets. You could make it automatic with some check valves (study the bridge rectifier diagram, replace diodes with check valves).

Then if you want to run the unit with solar-heated hot water, fine. In fact, you could automatically switch which heat exchanger is getting hot water pumped into its container (need overflow/return lines for both buckets, feed in the hot at the bottom and the cold at the top) and which gets cold (actually the water entering the solar panel). When the pressure drops the generator will stop spinning thus no current, it's a pretty simple circuit to sense that and switch some electric valves.

You could then scale it up, more and/or larger panels, an industrial pneumatic motor driving an automotive alternator... Oh the possibilities...

You Could Do This! The system works, the video show that much. And you will need neither hydride nor refrigerant, just some "slightly advanced" mechanical and electrical skills, and lots of patience towards lots of copper tubing. Hey, if you think you could make your own biodiesel processor then, good bet, you could do this. You.

BTW, 60% efficient solar? Apparently it has already been done, or is about to be. Using a heat engine, specifically a sealed system using hydrogen, with no moving parts. It was designed by a nuclear engineer with more than 100 patents. It's the guy who invented the Super Soaker. Click on the link, worth the read.

Oh, psst, it's mentioned in that article that its 60% efficiency is "...twice those of today's solar Stirling engines." So you know.


10 years ago

Point one - the hot water in the video seems to be close to boiling. Depending on whether the water in the cold bucket is iced, that's a temperature difference of between 60-90oC (140-200F). Most solar water heaters are marketed as reaching temperatures of 60oC. Assuming an ambient temperature of only 15oC, that's a temperature gradient of only 45oC.

Point two - the device had to be reversed every few seconds, implying that a set of (powered) valves would be required to switch the flow of hot and cold water between the ends of the device. That will inevitably reduce the temperature difference across the device as hot water flows through cold pipes and vice versa. The power consumption of the plumbing, plus their reliability, would have to be investigated.

Point three - don't be distracted by the light being labelled "1,000,000 candle power" - it was only 35W, enough to light one room with CFL bulbs. You would need about 20 such devices to run a microwave oven.

Point four - given points 1-3, there is no way this will achieve 60% efficiency in normal domestic situations.


That doesn't stop it being an interesting device, with potential for usefulness in some circumstances, but I would expect a simple Stirling engine would provide equivalent or greater operating efficiency, and they operate usefully on a lower temperature gradient. Solar-Stirling electrical generators already exist, and are claimed to be equivalent in efficiency to high-end photo-voltaic systems.


Reply 10 years ago

thanks for the information ill look into the Solar-Stirling electrical generators