solar cells, Full story at http://www.physorg.com/news103997338.html

http://www.physorg.com/news103997338.html

Seperate positive and negative charges! I dont think so!

Sounds like really good thinking, i wonder what the output from one cm2 would be?
" Scientists estimate nanotubes to be 50,000 times smaller than a human hair. Nevertheless, just one nanotube can conduct current better than any conventional electrical wire. “Actually, nanotubes are significantly better conductors than copper,” Mitra added."

a human hair's diameter is somewhere between 17 to 100 micrometers depending on color(?) which are 1 micrometer = 0.001 millimeters so if i take a median it would be something like 50000 x 0,040 (guessing :) which makes 2000 nanotubes per one 'mediandiametric' hair a. 0.040 mm. which goes 25 times to one mm which gives us 25x2000 (nannotubes) x 100 (= cm2 :) which should make it 5000 000 nannotubes per cm2 (hope my math worked here :) Now, how much energy would one nannotube produce?

This post has been edited by yor_on on Jul 18 2007, 11:49 PM

Probably, like most solar cells, only a fraction of one volt. Very, very inefficient still.

Electrons (negative) and the substance they came from that would like them back (positive). I think that is all they meant by that; not shuffling positive charges around or anything.

This is interesting but it sounds like a very early stage in the research. Anything that would use less or no silicon metal or other expensive materials would be great.

yawn, solar is weak

If this works I would jump on it, Ive always wanted to get off the grid. But what would be even cooler is a ZPM or nuclear roof panels!

Inefficient doesn't matter if it's cheap. So you need to cover 2 acres with solar cells instead of 4 to power your house. At these prices it puts independent solar power for every home into the range of "Possible" AND at less than the cost of the power bills. It used to take 10 years for the solar cells to "Pay for themselves". Now it takes one year. One year, and you'll never have to pay the power company for so much as a single watt ever again.

It would be GREAT if Solar could actually pay for itself in 10 years, but without subsidies and at TYPICAL electrical rates that's about 1/2 the time most systems need.

One year?

Only in your dreams.

Arthur

2 bones to pick.
Firstly the title is inaccurate. It sounds like they are a long way off. The process for producing or manipulating carbon nanotubes is nowhere near ready for home use. They don't even quote the theoretical or experimental $/W. Secondly there are no useful metrics at all in the article whatsoever. Another waste of my time.
A better title would be "A novel idea for potentially low cost organic solar cells".

One year? I don't think so. Never have to pay for another watt again? No solar system is that efficient. You still need to be wired to the grid and it is nice if there is some power left over after your usage and you can add your power to the grid in exchange for lower rates. However, I doubt very highly that you will never have to pay for another watt again. No one I know with solar ever has gotten into that deal. But, I do not use solar and really have no need. My bills are quite low (never more than $25.00 or so a month) due to the rather green nature of my cooling and heating systems. Both are very efficient for where I live in the desert. I can have 76 degrees in triple-digit summers and the same when it gets to below zero at times (usually doesn't get that low but this year was quite strange)--all for the same low price.

How many kilowatt hours do you go through on a typical month and are your months all about the same?

My rough calculations would suggest that you use about 10 kWhs per day

Which at 8 hours per day of direct sunshine (favorable desert SW conditions) would require ~ 8 160 watt collectors, an inverter and if we assume you don't use any kind of storage system but draw extra power when you need it from the grid and spin the meter back when you don't, you would be looking at about a $9,000 system. The annual interest on the cost of the system is greater than the annual cost of your electricity, so the system would NEVER pay for itself.

Many financial analysis of solar systems LEAVE OUT the COST OF MONEY.

They simply take the cost of the system and divide by the average monthly bill and proclaim the result to be the payback time. This ignores the fact that the cost of the system is front loaded. A simple example is you might buy a house for $100,000 but by the time you pay off the loan with interest your payments will total much more.

PV systems continue their trend towards getting closer to being financially viable, but without subsidies (and allowing you to spin the meter backwards is a huge subsidy), they still need to cut their installed cost by at least 1/3 for the best locations and more like in half for most others.

Arthur

Did you install the underground air resevoir for your heating/cooling? It is dicey to do where I live because of all the giant subterranean boulders, but my understanding is that in the desert it is a good way to provide for one's heat/cooling.

I keep seeing comments like solar is weak or only produces a few volts. I don't disagree with these but I think the focus and attention should shift and technologies like this (and other current solar advances) can help.

This shift is from the micro to the macro. I might only save me a few bucks on my electric bill to put solar on my roof. I might get back the energy i burn from keeping my computer on all the time, or that extra light. Minimal for now - agreed.

But if something that works effectively, is easy to install (paint, printed, plastic) then I might be able to use it on my *whole* roof, so might my neighbors, and theirs and so on. In a neighborhood of 1000 even 1% adoption isn't that bad. If you expand that to other communities, counties and states that 1% means a lot of people subsidizing minimal amounts of current with energy from the Sun.

This means less coal, less carbon, etc... i just see the effect of large numbers with solar adoption

--isi

Actually, you can do FAR MORE, by simple things like not running your computer all the time, switching to fluor lights, buying energy efficient appliances, upgrading insulation etc.

Conservation is our single EASIEST thing to do and it generally costs very little and/or has a quick payback.

Significantly, if you DO want to go to PV in the future, the thing that will lower the initial investment the MOST is if you have already OPTIMIZED your usage of energy.

But NO, a 0.01% adoption rate of ANY technology at the end user level will have no impact at all.

Arthur

I agree with Googleplex, that the cost of Nanotubes is presently extremely prohibitive. This research is trumpeting the enormously reduced manufacturing cost, using this technology, but fails to admit that the cost of raw materials makes using nanotubes astronomically more expensive than silicon. When nanotube paint is widely available, even without any photovoltaic potential, probably the paint company really will be able to stand by that lifetime guarantee. In fact, perhaps a home painted with nanotubes will be able to withstand a reentry from orbit, like the space shuttle.
Maybe the reasearchers have already formed a company to exploit this technology.
If they have, then we shouldn't be surprised if they market a ten dollar printer, to print photovoltaic sheets, and then charge $2000 for the ink cartridge.
Kind of typical marketing in the inkjet technology biz, isn't it?