Sandia Labs' new SunCatcher power system resembles Magritte painting
The news release from Sandia National Laboratories says the SunCatcher power system (above) unveiled at the National Solar Thermal Test Facility today is the result of a design partnership with Stirling Energy Systems and Tessera Solar. But I think they really designed 'em with Belgian surrealist painter René Magritte. Yes, I know he died in 1967, but the gubmint's secret art-zombie time travel machines address that matter. Duh.
the latest
latest episodes
I was thinking more Anish Kapoor
and these work how? focusing the suns rays on what looks to be an old crt computer monitor doesn't seem very intelligent. then again if it's some sort of high density steam turbine or solar panel i guess it would make more sense...
Just looks like a bigger version of one of these: http://www.flickr.com/photos/autarken/2094018472/
@HOFFMANBIKE #2:
I suspect the fact that they're partnered with Stirling Energy Systems is a pretty good clue as to what that CRT-monitor-looking thingus actually is. Without Googling, I'd expect that the business end of that reflector has a Stirling-cycle heat engine stuck to it, the better to produce tasty electricity with.
@Hoffmanbike
AFAIK they are steam turbines. They're using a concave reflector dish, but you could just as easily use a huge magnifying glass, but reflective dishes are cheaper. They concentrate the thermal energy on a small point, that boils water, steam turns a thingy, thingy has a magnet in it, magnet is surrounded by a coil, and voila, current.
@rak0ribz
really??? oh wow i figured they'd be using a regular ol' turbine. using a stirling engine is much, much more awesome.
*nerdgasm*
@hoffmanbike: Hmmmm.... I wonder if the answer could be contained in the link somehow.
nutbastard: Actually it uses a Stirling engine, as the link notes. It's similar to a steam engine, in that it has pistons, but is different.
These look really cool. They could well represent the future of solar power plants.
They're Stirling engines. I've been there, seen them, talked to the engineers and scientists. Those particular ones are, IIRC, based on a Stirling engine made by the Swedish firm Kockums. They were originally designed for auxiliary power for submarines and ships. They're not too bad, but, in my opinion, kinematic Stirling engines lose out to free piston designs, or will, as soon as free piston designs can be adequately scaled up. The efficiency is similar in both, but free piston designs are much more reliable, so much so that they can be welded shut, the better to retain the valuable helium they use as a working fluid. The Kockums engines leak a little, so they require some periodic topping up, plus there's much more mechanical maintenance. Still, they're quite efficient (typically 50-60% of Carnot efficiency), relatively cheap, and already available in sizes up to 25 kW, whereas free piston designs larger than 1 kW are not yet readily achieved.
@NUTBASTARD
I just got back from the press release page...
From the press release:
The modular CSP SunCatcher uses precision mirrors attached to a parabolic dish to focus the sun’s rays onto a receiver, which transmits the heat to a Stirling engine. The engine is a sealed system filled with hydrogen. As the gas heats and cools, its pressure rises and falls. The change in pressure drives the piston inside the engine, producing mechanical power, which in turn drives a generator and makes electricity
So, not only is it a Stirling engine, it's filled with Hydrogen, for twice the awesome.
Interesting. The older ones used helium. Hydrogen is much cheaper, of course, but isn't quite as perfect from a thermodynamics perspective as helium is. Helium more closely approximates an ideal gas, whereas hydrogen, being diatomic, has some funky non-ideal stuff going on. Still, it works quite well. Hell, I've built Stirling engines that use air, and even those will work halfway decently.
This is not a solar energy device.
@forgeworld: how do you figure?
Whoever licenses the IP for this should really buy a piece of General Motors. Or a few of their bankrupt body panel/power window controller/AC compressor suppliers...
Aussi ceci n'est pas une pipe.
Forgeworld is right you know. These are a new prototype of mind control lasers / HAARP death rays.
That's actually a very good idea as far as repurposing GM or suppliers to build things like this. I'd hope that there are negotiations going on right now, otherwise someone isn't on the ball.
Large kinematic Stirling engines are really quite simple, and any manufacturer that can make auto parts should be able to retool to build them. The same goes for the support frames and tracking systems.
I do think the Infinia system is much cooler than the SES/Tessera design, and I know that SES has had meetings with Infinia to discuss licensing of their engine. The Infinia engine is a free piston design, and has just gone into production in a 3kW size, with plans to scale up to 18kW soon. The Infinia engine uses helium as a working fluid, so it's a little more efficient, but the main difference is the fact that it's a free piston design. There are two piston in a Stirling engine, the displacer piston and the power piston. The displacer piston is lightweight and doesn't seal against the cylinder and simply displaces heated gas from the receiver up to the cylinder for the power piston, where the gas cools, sucking in the power piston and doing useful work. In kinematic engines, there's a crank connecting the two pistons and a flywheel with a counterweight to follow through on the motion and reset the system off the energy of the power piston. In free piston designs the pistons are attached the the cylinder wall with flexure bearings, which are like a flat spiral of metal which acts as a spring, and resetting of the displacer is done through acoustic/spring resonance. The movement and cooling of the gas creates a pressure wave, which gives a small kick to the displacer, and the whole system is tuned so that this kick arrives timed such that it drives the flexure bearing at resonance. It's a very cool design, and incredibly reliable due to the reduction of moving parts and the elimination of any sliding friction in the displacer. But, scaling it up to a larger system is not as easy due to the need for this acoustic/spring resonance to keep it running. That makes for some trickier engineering, but still, not too bad and completely achievable. The Infinia design goes one step further and uses a linear alternator coupled to the power piston to generate power. Combined with the fact that they tune the acoustic/spring resonance to operate a 60 Hz, and you get grid-ready AC directly out of it. So, you have a device that's about 30% efficient, maybe a bit more, and you don't have the loss of going through an inverter which can shave 5-10% off your hard won power before it hits the grid. Plus, the linear alternator doubles as a solenoid to get the thing started in the morning. All it takes is a few pulses timed just right, after the heat receiver has gotten warm enough, and off it goes. All Stirling engines need a starting push, but only the Infinia design combines this function with the alternator, again reducing the part count. Right now they're making 1 kW systems for micro-CHP applications, where they run off waste heat from natural gas boilers for heating and domestic hot water, and they're making a 3kW solar system for small scale remote power generation. There are a few of those at the test area at Sandia as well.
These are intended for residential use, and are about the size of an old fashioned 1980s satellite TV dish. I'm not sure what their price is, but it's expected to come down quite quickly as they scale up engine manufacturing. The Infinia engines I've seen were all prototype or early production ones, hand built by very talented machinists, and were absolutely beautiful, every piece finished and fit like a Swiss watch. Unfortunately, this is not an economically feasible way to make them, so the production models are not quite as pretty, but they certainly work just as well.
@forgeweld: kudos!
Sandia Labs is an anagram for Sand Labia
I didn't get FORGEWELD @ 11 until I read DWITTSF @ 14. But actually FORGEWELD is right. It is not a solar energy device. It is a picture of a solar energy device.
why do these things have to be as big as a house and attached to a grid? why couldnt we all have one on our rooftops or backyards and feed them directly into our houses?