Nanotubes May Improve Solar Energy Harvesting

eldavojohn writes "Scientists are hoping that the 'coaxial cable' style nanotube they developed will resolve energy issues that come with converting sunlight to energy. The plants currently have us beat in this department but research is discovering new ways to eliminate inefficiencies in transferring photons to energy. Traditional methods involve exciting electrons to the point of jumping to a higher state which leaves 'holes.' Unfortunately, these electrons and holes remain in the same regions and therefore tend to recombine. The new nanotubes hope to route these excited electrons off in the same way a coaxial cable allows a return route for electrons. End result is fewer electrons settling back into their holes once they are elevated out of them yielding a higher return in energy."

Comments

Re:Concentrating existing power also important

[Rukie]

Nanotubes have been around for some time now, but these look like they are structured differently and with different materials. Although, I do believe the problem isn't so much as "efficiency" as it is "price." Once solar energy becomes competitive/better than fossil fuels, I think we will see a huge increase in hydrogen storage (for batteries) and solar energy, along with wind mills for n ighttime power and cloudy days.

In fact, they even have clear glass windows that college solar energy as well (might have been on slashdot?) We definitely have the ability, were just willing to spend the resources.

Centralization is the wrong way to go

[StefanJ]

The infrastructure required to transfer electricity from centralized facilities, and the losses suffered along the way, don't make this very appealing.

A panel on your roof may not be as efficient, but it's yours. In an sunny place, you may be able to sell power to the local grid during the daytime peak hours. (You might buy it back at night, but the rates are lower then.)

There will always be a need for a grid, and some big power plants, but making as much new capacity decentralized and as local as possible means addressing political, social, and security externalities that have been ignored thus far.

Re:Centralization is the wrong way to go

[Rei]

The problem is that insolation varies greatly around the world. I would very much love to get solar panels for my house, but up here in Iowa, we get half as much sun as the desert southwest. Yet, we're positively awash in solar energy compared to, say, Washington and Alaska, which have half what we get here.

Halving the amount of energy doesn't just double payback time when you consider cost amortization. It increases it many more times, often making it so that it will never pay back.

Now, up here, self-generated wind power is an economically viable alternative to grid power... *if you don't live in a city*. I've crunched the numbers. Inside city limits, your towers are more expensive (you can't use guyed towers -- not enough space) and your heights are limited too close to the ground. On the other hand, it's perfectly reasonable for farms (and power companies) to invest in. One great thing about the big tower wind turbines is that you lose almost no ground area; you can farm nearly up to their base.

Only 5 Years Away

[Nom du Keyboard]

And I'm sure this is only 5 years away from commercial use, just like every other such announcement.

Re:Wrong headline

[Rei]

Unfortunately, "works in a lab" and "mass producable at a commercially viable price in the remotely near future" are two very different things. The former only rarely becomes the latter in fields like solar power. Thankfully, there are so many advancements that a few always tend to make it and push the industry forward.

Just the small matter of tdynamics and economics..

[Ancient_Hacker]

Expecting nanotubes to act as "maxwell's Demons" is well on the way to Polyanna-Thinking. Fine for used-car ads, political spots, and grant proposals. But a bit far-fetched for rational discussion.

Plus on the economic issue, most nano-things cost kilobucks per square centimeter. Even if the cost came down by a factor of 10,000, it would still be uneconomical at ThunderDome prices.

Re:Concentrating existing power also important

[Pxtl]

That was my reaction too. Energy-innefficient solar collectors aren't really a huge concern so much as the dollar-per-watt efficiency. I mean really, the reason people aren't solar-panelling their rooftops isn't that they don't have enough roof, but that they don't have enough coin.

Zeno's power cell

[jfengel]

I'm planning to tag every solar-power story "vaporware" until I see something that doesn't depend on additional breakthroughs before it comes to market. It seems like we get 50% of the way to something useful with every posting but never actually get anywhere.

Plants have us beat?

[mdsolar]

The link to the situation with plants shows how plants work at the quantum level but just a bit of thought shows that we are more efficient than (rooted) plants at collecting solar power. A small area, say all of the roof tops in the country, can cover all of our electric use and more using 15% efficient silicon solar panels. On the other hand, all of the arable land in the US is not enough to cover our transportation needs through biofuels. Plants may be efficient for their own purposes, but in terms of energy harvesting we do better on our own http://mdsolar.blogspot.com/2007/02/photosynthesis .html. And, as the article points out, we are on the way to doing even better.
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Sprout Silicon Leaves: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html

This depends

[mdsolar]

At the 15% efficiency of silicon, quite a lot of roofs have enough area to cover what a building uses. Orientiation comes into this as well as the height of the building. Taller buildings have less roof per unit floor space which tends to track electicity use. At 7% efficiency, the number of roofs that can cover 100% of the building's use goes down a lot because we're at the edge of feasability at 15%. So, cheaper, lower efficiency solar panels, can turn out to work better where surface area is not at a cost premium. This tends to be in rural areas rather than where most houses are.

Commercial buildings can often benefit from lower cost, low efficiency panels because they are gaining from using space that they otherwise would not and they are more bottom line driven and can't cover they're full electic use under either senario.
--
Go Solar for what you already pay anyway: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html

Re:This depends

[QuickFox]

Glad you were so quick to offer help back then. I appreciate that you noticed.

if you want to send some of that gas tax to us to cover our defense spending, Sorry, that's impossible, because Sweden disagrees with your methods. I don't know how Sweden's official motivation is worded, but among the general public the mainstream opinion is that the Iraq war is fueling terrorism rather than curbing it, and we don't want to fuel terrorism. This is not some after-the-fact observation, it has been the firm mainstream opinion since well before the Iraq war started.

OTOH we have Swedish troops in Afghanistan.

Speaking of our relationship, I do feel that we and the US, in fact the entire Europe and the US, need to be much stronger allies than we are, in spite of the differences that we have. We need to make every effort co-operate in those areas where we agree. We have lots of common goals, and there are lots of areas where we agree.

In fact, even when we disagree we could often co-operate. For instance, we might play good-cop/bad-cop roles when dealing with recalcitrant nations. That's far more constructive than building rivalries.

I think we could achieve lots of great things together if we could just co-operate better.