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SHPEGS — DIY Solar/Geothermal Electricity
rohar writes "SHPEGS is an open design not-for-profit project to design and prototype a base-load renewable electrical generation system suitable for moderate climates and built from common materials. The design centers around creating a local geothermal source with an efficient solar thermal water heater system and can be scaled from single residence to mega-scale. The heliostat system used in Europe's first solar thermal plant could be used in a scaled-down SHPEGS system with Practical Solar's small scale heliostats."
Isn't this just the Energytower renamed?
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I read though the site and found many calculations but I'm trying to figure out the actual efficiency of converting solar energy to electricity. I don't mind if the hot water out gets counted at 100% but I'm guessing that per unit area this does not do as well as silicon PV at 15%. If there is a table that gives this kind of comparison, can someone please point it out? Thanks.s -selling-solar.html
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RS
Shoes for Industry. Shoes for the Dead.
Am I the only one who instantly thought of Arj Barker when reading that headline?
Too long to be shorts
Too short to be pants
Shpants!
ah-ah-ah
uh-ah-ah
oh-oh-oh
Yeah, I thought so...
I'm pretty sure I already read about the effect that a planet's core cooling would have on/in Abarrach, the world of stone.
That book kind of creeped me out back when it first came out. I was a bit younger then though, and the rather violent necromancy used in the story was scaryish to a fragile young lad like myself.
I'll give you a hint, this book ends badly for many involved.
Damned entertaining though, and I avidly waited for the next book in the series.
All kidding aside, I will be watching this project. I keep hearing that if you can generate your own electricity and give back surplus to the grid then the power company has to pay you. I can't wait for the day I can call my utilities company and tell them they have 10 days to pay up or I will be forced to hand deliver a final notice!
I still don't get the "why"?
Congratulations, you can insert Heroes (right? I don't watch the show myself, so I'm not sure) spoilers into an otherwise good post... so what?
Try not to take me more seriously than I take myself.
Mongrel News all the news that fits and froths
A lot of the SHPEGS system inspiration came from the Drake Landing Solar Community project which is a district heating system using solar thermal collectors on the garage roofs and borehole thermal storage for structure heating.
For colder locations, there is a lot of value in the structure heating component of the SHPEGS system.That thing has an incredibly complex cycle, with losses all along the chain. There's ammonia, water, steam, air, and hot oil involved, with heat exchangers all over the place. The paper attached to it doesn't describe the basic thermodynamics in any real detail. It's sort of like a solar-powered Rankin cycle system. But much more complex, and without solid justification for the extra complexity.
This might be credible if they had a working prototype, even a little one. A prototype in the 1 KW range would be about right. That's a backyard project. A 1KW plant would need about 10 square meters of collector mirror, which isn't too hard. Then they'd have something. All they have now is hype.
I currently live in Indonesia, where people commonly burn rubbish - including farmers who burn the husks from rice production. Although this certainly isn't the most environmental form of waste management, I feel that if they are already burning rubbish, at least they could collect the energy from the burning?
Would it be possible to build a simple generator to convert the energy into electricity?
The Canadian system looks like it would be about 2% efficient. So, you'd want a collecting area perhaps 6 times larger that roof area of the homes served. So, if it served a town it would need about that much land again. The big plus is power storage so I wonder if it could be tweaked more to serve in the Winter and handle Summer/daytime with PV directly?
If we are to believe even half of what Al Gore is spouting
How could you NOT believe Al Gore? After all, he DID invent the internet!
Seven puppies were harmed during the making of this post.
Using geothermal power will speed up the cooling of the earths core.
????????
Seriously do you have any kind of idea of the amount of energy required to cause any sort of noticeable impact on the earth's core? It's like a colony of ants saying they will destroy all the buildings in Manhattan.
Seven puppies were harmed during the making of this post.
I recently read an article about solar power in Wired magazine: http://www.wired.com/wired/archive/13.07/solar.htm l
c hoid_of_nic.html
o r_Collectors.htm but it was not much help.
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The article mentions a new design for a concentrator that only uses two motors. To quote the article -
"Then, in a weekend flash of inspiration, a young Caltech physics grad named Kevin Hickerson figured out how to reduce the number of motors needed to move 25 mirrors independently, a major cost factor. Instead of two motors for each mirror - the traditional approach - Hickerson's solution requires only two motors for any number of mirrors. The key is a mathematical curve known as the conchoid of Nicomedes (named for the ancient Greek mathematician, who discovered it). A grid of ball bearings arrayed to match the conchoid is attached to a frame inside the Sunflower. As the motors move the frame, the bearings control each mirror's position individually."
I have found this but it is not helping me much:
http://nvizx.typepad.com/nvizx_weblog/2005/08/con
I have been unable to locate a more detailed explanation of the system and I'm not sure if this basic math is patentable. My advanced math skills are very rusty and I'm not quite sure where to start to understand this. I have an idea that this technique might be useful and I want to understand how to design such a frame. I did look at the concentrator page here: http://www.sandia.gov/pv/docs/PVFarraysConcentrat
These articles as well also have some implications for the benefits of a simple energy source:
http://science.slashdot.org/article.pl?sid=05/09/
http://www.time.com/time/magazine/printout/0,8816
Also, this today triggered my interest again:
http://www.renewableenergyaccess.com/rea/news/sto
I want to understand how to make a spreadsheet or something that would allow me to input number mirrors, focal length, size and it tell me shape, size a location of pivots. Can you explain it to someone who hasn't touched calculus in 18 years? I want to build a cheap one on my roof!
"I say we take off, nuke the site from orbit. It's the only way to be sure."
Jake: SCMODS?
Photovoltaics are additive - double the area and you only get twice the power. Thermal solutions scale up. If you only look at the small scale it is not going to look very good.
Someone had to do it.
I'm not being rude, but is the answer anything like the answer to "do you have any kind of idea just how much oil there is"? I mean, ants COULD destroy all the buildings in Manhattan if the buildings weren't repaired and the ants had long enough.
Yes, the fabrication of these stand-alone systems would cost quite a bit of money at first, but there must be enough "engineering intelligence" available at this time to allow workable, extremely low maintenance designs to be created.
All to often it seem simple designs are overlooked in favor of large scale "plants" for generating electricity because we only have to build one (whoopie) and they employ local citizens providing economic support to the planet's community. We have been creating a system of dependencies instead of independent (distributed) solutions. It is old school thinking at its worst that is past due for retirement!
Also, I offer that the widely distributed power generating model is "insulated" against natural disasters and terrorism because if 20 to 70 percent of a "grid" is knocked offline, only that 20 to 70 percent is effected. In our current configuration one power plant taken out of service may leave millions in the dark and without support for their electronic gadgetry.
Has all this been mentioned before? Probably. But I feel the technical community-at-large has to continually raise its collective voice in favor of systems of updated design. American stockholders may take a hit by the loss of assest invested in decades old technology, but think of this in comparison to so called third-world countries leaping over "land line" phones and going directly to wireless! All of the money they save by NOT investing in wired communications infrastructure is being (or should be being) directed into lower cost, lower maintenance innovative new technologies delivering the same services.
Current power and communications systems should be kept as backups only and we as a nation should be encouraging people to get off the grid rather than plug into it.
Informative? WTF??? How can you call informative a comment that says basically nothing and doesn't even inform the acronym right?
OTOH, another moderator gave to the first answer to that trollish comment a (Score:-1, Flamebait) because it gave information on some shortcomings of the SHPEGS concept.
Well, let's just hope I get some of those dumbasses in meta-moderation...
It is true that heat retention improves with scale linearly and delta T can be increased with scale, but the cost goes up with volume (linear scale^3). One nice aspect of this system is that you might build it to last a few centuries in the below ground hardware so that the cost per unit time is low. It is difficult though to arrange multi-generational financing of this duration so the first users have to carry the install costs.
s -selling-solar.html
PV scales as you say, but the cost comes down a lot with large scale manufaturing, and the cradle-to-cradle-to-cradle aspects of recycling the PV look pretty positive so it carries reduced costs forward but in a way that spreads them without having to work out new finacial instruments.
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mods have no fucking sense of humor, as usual. Bleh, I'm a karma millionaire
Seven puppies were harmed during the making of this post.
I mean, ants COULD destroy all the buildings in Manhattan if the buildings weren't repaired and the ants had long enough.
Unless of course people keep building. Do you have any idea why the earth's core is hot? Do you just think the earth is cooling, still, after a few billion years, and will continue to do so for another few billion? Do you think there are no GRAVITATIONAL FORCES from the Sun that actually knead the inside of the earth like dough, and THIS is what heats the core? The core will cool when the earth stops rotating. Period. Now, how will tapping geothermal energy stop the rotation of the Earth or reduce the sun's gravity, pray tell?
Seven puppies were harmed during the making of this post.
Here is a set of concentrators that run on a single motor. This might reduce PV cost by half though I'd worry about using this where there is snow and ice: http://www.technologyreview.com/Energy/18718/. This is coming to market this year. They are also working on a 2-D array.s -selling-solar.html
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Umm... no... the Earth's core will cool when the residual heat from it's formation bleeds away, and the various radioactive elements that are responsible for heating it finish breaking down into lighter elements. Period.
I bet that's what they said about oil too...
Perhaps it's a sophisticated submission to the slashdot "turing test?"
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http://www.energyinnovations.com/sunflower250.html is the two-axis concentrator. It's a bit worrying that the website appears unchanged since 2006 and commercial trials were supposed to start in 2007. But supposedly Google's going with their subsidiary for a 1.6MW system.
Under Technology their web site describes all the approaches they considered and reluctantly abandoned. Very interesting read.
=S