Carbon Nanotube Solar Cells On the Horizon

MikeChino writes Carbon nanotube news abounds as of late, and the next application for the up and coming material may be hyper-efficient and economical solar cells. Led by professor Paul McEuen, researchers at Cornell recently tested a simple solar cell (called a photodiode) crafted from a single carbon nanotube. Surprisingly, researchers discovered that more light shined on the nanotube created even more electricity, a huge difference from today's silicon solar cells where excess energy is lost in the form of heat rather than used to create more electricity."

Comments

The technology isn't important

[davidwr]

The question is, it it cost-effective?

New title:

More cost-effective Solar Cells On the Horizon

There, fixed that for you.

Re:The technology isn't important

[Anonymous Coward]

The question is, it it cost-effective?

New title:

More cost-effective Solar Cells On the Horizon

There, fixed that for you.

New solar cells that are "more cost-effective" require new technology.
New technology requires research.
Research is an expensive process.

To make new, more cost effective solar cells, we need to fund _some_ technology. Carbon Nanotubes are promising.
Press releases get a college department more funding, which buys new equipment and affords more people working on a subject area.

So, in short, the fact that this technology is related to Carbon Nanotubes is intrinsically important.

Re:The technology isn't important

[bugnuts]

Considering the energy required to produce crystalline Si cells, if the manufacturing is perfected, it could be both more efficient and cheaper. A solar pv panel today must produce energy for a year or two to recover the energy used to create it. Nanotubes may be much more complex, but they probably need nowhere near as much power to create.

The bottom line Is what generally matters to consumers, but the cells must still be efficient because roof real estate is not unlimited.

Re:The technology isn't important

[kheldan]

The question is, it it cost-effective?

If someone developed a 99% efficient solar cell, would you really care what it cost?

Re:The technology isn't important

[Idiomatick]

Yes... that's stupid. Of course it matters what it cost.

Re:The technology isn't important

[camperdave]

Yeah, but you can buy tubes of silicone at any hardware store. It ain't exactly rare.

Re:The technology isn't important

[Da Fokka]

If someone developed a 99% efficient solar cell, would you really care what it cost?

You're kidding right?

For everyone who is looking for real solutions (unfortunately that's not quite everyone in the debate), the cost is a crucial factor in the equation. Economic efficiency is more important than energy efficiency.

Re:The technology isn't important

[drseuk]

It's a great finding, but unfortunately, making nanotubes is a HIGHLY energy intensive process

Obviously we need someone to invent some sort of hyper-efficient, clean and renewable energy source to power the manufacturing process then.

Re:The technology isn't important

[Aceticon]

Well, if somebody developed a 150% efficient solar cell I wouldn't care about cost.

Then again, you could use such a solar cell to power some high efficiency light producing device (say, a LED) which you would point at the solar cell thus getting back more energy than you used to power the light (i.e. free energy).

Re:The technology isn't important

[jonadab]

> Economic Efficiency is a non-stable and non-quantifiable metric.

There are limits to how precisely it can be pinned down, but some arrangements are obviously more reasonable than others.

> In the real world, such calculations have 'proved' that
> the United States doesn't need high speed cargo rail,

That conclusion is correct. The problem with any railroad is that it's only practical when huge amounts of cargo (or passengers for that matter) need to travel exactly the same route all the time. We do use it for things like taking coal to steel mills, but delivery speed doesn't matter there. A high-speed cargo rail would have VERY limited applicability in the United States. If you're from Europe or southern California, you might really have a sense of this until you drive across the Midwestern US in a car a couple of times. Put simply, only a small percentage of our cargo starts or stops at a major city.

> it just needs to keep subsidising the airlines.

That's a separate issue and not significantly related to the rail question. The airlines mostly handle passenger traffic and mail. Almost all cargo goes on eighteen-wheeled semi trucks, because they can deliver to any destination.

> It's 'proved' that shipping from say, Nice to Tuniz by truck,
> through nations such as Lebanon, in time of war, is 'better'
> than shipping straight across the sea by blimp.

Any kind of reasoning can fail of the person applying it fails to take important factors (such as war, for instance) into account. That's neither here nor there.

> NO consequence is bad enough to make you not take an offer,
> IF the consequence occurs far enough in the future

That's a straw man, and not a particularly clever one. Nobody in the history of the universe has ever seriously argued in favor of doing anything that they knew would destroy their entire race a couple of centuries down the road. Nobody. Ever.

Economic efficiency *does* matter for solar cells, and ones that are cheaper to manufacture (for any given level of energy output) are better, and such research is important, because if the solar panels can pay for themselves in a year and continue producing energy for ten or twenty years, people *will* buy and install and use them; whereas, currently most people are not buying or installing or using them, because they don't produce enough energy to pay for themselves fast enough to cover the opportunity cost of whatever else people could buy with the same money.

I don't know whether these nanotubes will lead to the kind of solar cells that are really needed, or whether it's a blind alley. The researchers don't know that either. But in the absence of any knowledge of a *better* technology, it's worth exploring the possibility.

Re:The technology isn't important

[Lloyd_Bryant]

no.... if it costs 10x current solar prices to ramp it up to 99% then it doesn't really help does it. I mean maybe for some weird science use but not for energy production.

TFA is a little light on details, but consider this quote: "Researchers discovered that more light shined on the nanotube created even more electricity, a huge difference from today's silicon solar cells where excess energy is lost in the form of heat rather than used to create more electricity."

So say it's 10x the current price of solar cells, but can utilize cheap mirrors so that you only need 1/10 as many of them as conventional solar cells.

There *is* some potential here (assuming it actually works on a larger scale, of course).

Homer says...

[Azghoul]

Carbon nanotubes... is there anything they _can't_ do?

Re:Homer says...

[Anonymous Coward]

They have yet to get me a date with Megan Fox.

Re:Homer says...

[idontgno]

We need a huge ticker-tape parade for our hero, Inanimate Carbon Nanotube.

Re:Homer says...

[kheldan]

Carbon nanotubes can't be mass produced economically yet.

There, fixed that for you.

Yikes, what an article!

[Maury Markowitz]

Did anyone else conclude that article was written by someone who had little idea what they were talking about? Note that "light" doesn't enter the description until after they talk about running power through it. And not one number.

Ooh, ooh

[russotto]

Another world changing technology that's just around the corner.

Re:Ooh, ooh

[H0p313ss]

Another world changing technology that's just around the corner.

Just for fun, if you're old enough, try to remember what things were like 35 years ago in the mid 70's:

• The internet was essentially a private network that most of us didn't hear about until the late 80s...
• No PCs, a portable computer was a dummy terminal PRINTER with a 300 baud modem
• Cell phones the size of lunch boxes
• Giant floppy disks with less that 1MB capacity.

These days the average (new) cell phone is more powerful than all the computing resources used by the Apollo program. Heck I carry my ENTIRE music collection around with me every day!

Now try to imagine the world in 35 years.... it's just around the corner.

Re:Ooh, ooh

[seven of five]

I think it's pretty amazing, actually, that a cellphone sized computer could be used to perform (and now, perhaps even automate - as in run an autopilot program) all the calculations necessary to control a spacecraft intended to fly to the moon and back.

There's an app for that.

Again with the #$##%# solar cells

[McGregorMortis]

Not a week goes by that you don't hear about yet another breakthrough in cheap and efficient solar cells. Every week, without fail, since 1979, I swear to God. Any more grains of salt, and I'll have a heart attack.

Re:Again with the #$##%# solar cells

[MyLongNickName]

Here is an anecdote I found in my search

"Scott,
The price of PV modules has come down in the last year, although not quite as much as the Times article suggests. I don't think there has been any significant drop in the cost of inverters, racks, cable, or installation labor.

My first PV module cost me $8.33 per watt in 1980. I paid $3.97 per watt in 2004, and $3.99 per watt in April 2009. Current PV module prices can be as low as $3 a watt, but only if you buy a whole pallet of modules. Otherwise you're still liable to pay $3.50 to $3.96 a watt"

So, since the year 1979 which the GP references, prices to the consumer have dropped more than 50%, even without adjusting for inflation. After accounting for inflation, you are looking at solar being 5 times cheaper than 30 years ago. Not bad.

I know it is poor form to extrapolate like this, but if we had a similar improvement over the next thirty years, then solar would easily become the number one source of energy worldwide. that may or many not come to pass, but the overall point is that despite the jaded responses from folks, we are seeing dramatic improvement in the price/performance of solar.

Re:Again with the #$##%# solar cells

[Firethorn]

On the plus side, the cost of solar panel is expected to hit 1 dollar a watt by before the end of 2010, and as cheap as 50 cents a watt by the end of 2012.

Do you have a link on that?

If true, the only thing remaining would be to drop the ancillerary costs to a similar level. Right now that's running around $1/watt itself.

For example, a 6kw inverter runs $3.6k. That's $.50/watt right there, without getting into wiring, mounting costs for the panels, paying for the electrician to hook everything up*, etc...

*You can't count on everyone, or even a significant fraction of the population to be able to do this stuff themselves.

Future speak meets now tech.

[ZWarrior]

I, for one, thought the article was good for giving us a look into the future of the tech. Based on teh way things are rapid prototyped and built these days I would expect to see something like this hit the markets in 5-7 years, and the price become reasonable with 2-3 years after that. 10 years to a cheap and cost efficient power source is not bad.

Photoresistive, not photovoltaic

[Ancient_Hacker]

If you read TFA carefully it seems to be describing a PHOTORESISTOR, not a PHOTOVOLTAIC device.

They talk about APPLYING a potential difference across the thingy, and discovering it has a wide dynamic range OF RESISTANCE, not of any ability to generate voltage or current.

We don't need any more resistors, we have enough of them and they don't generate any power anyway.

This article is even more of a major fail than most.

Re:Photoresistive, not photovoltaic

[Anonymous Coward]

If you read TFA carefully it seems to be describing a PHOTORESISTOR, not a PHOTOVOLTAIC device.

But they describe it as a photo-diode. I'm going to take a leap of faith here and assume they know the difference.

Oh, and here is a link to the original page.

Re:On the Horizon? Really

[avandesande]

The important thing though is that with the linear response to photons light can be focused on the cells- even if they are expensive they could possibly be cost competitive with Si cells.