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Comment: Re:Challenge for tablet makers (Score 1) 274

by cgraves (#38006846) Attached to: Asus Unveils Quad-Core Transformer Prime Tablet
I've been looking for such a tablet as well. It would be great to properly make artwork and take notes with a stylus and run some of the usual software.

I was thinking about the Asus slate for a while, but now I have my eye on a Samsung tablet that they just released. The Samsung Series 7 Slate. It is very similar the Asus but slightly lighter, thinner, more widescreen, and longer battery life. Similar price. It looks like they are not quite meeting demand yet since it is sold out most places. There are a few configurations with 64gb or 128gb SSD drive and different "bundles" with dock and/or bluetooth keyboard and/or stand case. Best Buy Business, Microsoft Store.

Comment: scam behavior or not (Score 1) 828

by cgraves (#37874840) Attached to: 1 MW Cold Fusion Plant Supposedly To Come Online
I have been following this lightly for a while. On the one hand Rossi's history does not give confidence to this being real. On the other hand he doesn't seem to approach it like I would expect a scammer to approach it - he does get in touch with universities and professors, and he does not ask for money, even apparently financing the contruction of this 1 MW plant himself. Also holding a large-scale demonstration with big-name media present does not seem usual. If it is a hoax, I am not sure what he would get out of it besides publicity (being in the news).

There are 3 options: (1) it is a hoax/fraud, (2) he really believes it is true and cannot manage to do measurements correctly or is in some kind of denial and interprets the results incorrectly so they fit his beliefs, (3) it is true.

It is not clear whether this demonstration will make it clear. There have already been 11 other smaller-scale demonstrations and apparently there has never been conclusive evidence throughout all these. It also depends on who is vetting the test. There is someone from PESwiki there tweeting updates, tweeted "Q&A just finished; reading of results; 470 kW maintained continuously during self-sustain; customer satisfied; sale made; more later." and expects to post an article on the wiki/blog in the next hour or so. PESwiki historically has followed/reported on hundreds of bogus technologies. But the customer is satisfied? Who is the customer! Also an AP writer from NY is apparently attending the demo. However, a link to the likely writer says that he covers "telecommunications, consumer electronics, etc" for the AP, so it's not likely he is knowledgeable about energy technologies.

It will be very interesting to see the reports.

Here are the various semi-high-profile news articles about this technology that have recently been published, to collect them all in once place:
Forbes blog, Oct 28th
Wired, Oct 28th
Forbes blog, Oct 17th
Wired, Oct 6th
And then plenty of other sites like blogs and physorg since January of this year.

Comment: Re:Hmmm (Score 1) 50

by cgraves (#34673334) Attached to: New Solar Reactor Prototype Unveiled
I think you are missing a step. If you just put atmospheric air through such a reactor, you might split the CO2 to CO but it will be in a gas stream with 99.96% other gasses (N2 and O2).. then you must separate the CO. Might as well separate the CO2 up front and avoid wasting all that energy heating up so much excess gasses. One can capture CO2 from the air and supply it in a concentrated form to the solar reactor.

Comment: Re:not new (Score 1) 50

by cgraves (#34673238) Attached to: New Solar Reactor Prototype Unveiled

Water thermochemical cracking is probably the most efficient method of converting solar energy to chemical energy that we have, perhaps that even exists considering the inefficiency of electrolysis.

First, with present technology, this is incorrect. Using solar photovoltaic plus electrolysis to produce fuels (hydrogen, carbon monoxide, or a mixture (syngas) appropriate for liquid hydrocarbon fuel synthesis) can be done with >30% sunlight-to-syngas efficiency using expensive concentrated photovoltaics (~40%) combined with high-efficiency high temperature electrolysis (>90%, see here and here). So far no thermochemical cycle has been demonstrated to achieve such a high efficiency.

Second, it is not about efficiency. In many cases one can achieve very high efficiency at the expense of using expensive materials. The idea here is to use cheap ceria-based oxide materials in the solar thermochemical reactor instead of expensive high-purity silicon semiconductors and other semiconducting materials in photovoltaics or photoelectrochemical cells.

Comment: Re:About $2K savings per month (Score 1) 562

by cgraves (#31269526) Attached to: Fuel Cell Marvel "Bloom Box" Gaining Momentum
Lifespans are significantly longer than a year now. See Fig 9 on pg 11 of this recent overview of solid oxide fuel cell development. You can see that degradation is on the order of 1% per 1000 h (around 9% per year) during year-long tests of cell stacks. The Siemens-Westinghouse (SWPC in the figure) cell is even far below 1% but it is a more expensive cell. The next few in the list (HTAS/Risoe, Chubu, FZJ) represent more state-of-the-art planar cells.

Comment: Re:Magic (Score 1) 562

by cgraves (#31269444) Attached to: Fuel Cell Marvel "Bloom Box" Gaining Momentum
It is a solid oxide fuel cell. There is nothing magical.

It is presented like it is a brand new invention and that they are the only ones making the product, however R&D on this technology has been going on since the 1960s by big companies like Westinghouse, GE, and tens of other companies all over the world. DOE has a 10-year old still-active program dedicated just to SOFCs. There is a book about solid oxide fuel cells.

There is no platinum or other precious metals. It is ceramic oxides and nickel, similar to alkaline cells except these run at much higher rates per unit area which promises to make them cheaper than other types of cells. Read the links above for the materials. The electrodes are "inks" only during manufacturing - they are heat treated to form stable solid materials. Recently, developments in materials science has brought them close to commercialization (manufacturing cost and durability have been issues). Of the perhaps 50 companies attempting to commercialize this technology, it seems that the Bloom company is just the one that happens to be funded by silicon valley investors.

This is not to say the technology is not exciting and potentially can improve our use of fossil fuels. The same cells can also be run in the reverse direction as electrolyzers, applying renewable/nuclear (non-fossil) electricity to split water and carbon dioxide to create fuels (link1 link2).
Power

+ - 50% growth in solar production in 2007 to 3.8 GW->

Submitted by
mdsolar
mdsolar writes "Solar cell production experienced 50% growth worldwide producing 3.8 GW of cells in 2007. In the US, installation of solar power grew by 83% in 2007 over 2006 but the US fell to fifth place in solar cell production as Taiwan pulled into fourth place after Japan, China and Germany. The US holds a large lead in thin film solar production. Expanding polysilicon supplies are expected to bring the cost of solar panels to $2/Watt by 2010. The cost of production for thin film panels is expected to be below $1/Watt by 2010; competitive with coal power."
Link to Original Source

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