Nanosolar - low cost solar energy. Or not?

[steve s]

Was it these people?

It wasn't that particular one, but it was similar. The main difference was that this guy's blades extended all the way to the central axis. Also, I think he was from Chicago, because that's where he's been pushing his turbines. I couldn't find anything about him at the Science Channel site.

Also, his could operate with the axis verical or horizontal. They showed one rooftop where they had some laid out horizontally.

Steve S.

 

[quarky]

not to sound like a conspiracy theorist, but
In the late 70's/early 80's, there were frequent rumours about the cost of photo-voltaic power going down. Some of the estimates were so optomistic as to be woo.

Unfortunately, the news of the inevitable break-throughs, however fanciful , kept people from buying solar panels. Shortly after, most of the smallish companies making p-v panels were bought up by big oil.

 

[Matteo Martini]

Just read in the net:
The NYT quotes Nansolar's founder and CEO Martin Roscheisen saying, "With a $1-per-watt panel, it is possible to build $2-per-watt systems."
http://weblog.infoworld.com/sustainableit/archives/2007/12/solar_google_gr.html

With an expense of USD20000, you can have a 10KW system, which can power your electric car
http://www.carbodydesign.com/archive/2007/01/10-chevrolet-volt-concept/

 

[Cuddles]

Given the current cosp and efficiencies, cost per watt is probably the important factor (efficiency is obviously going to be an important factor in this cost, of course, as less silicon is good).

Yeah, I have to concede that you're probably both right. Efficiency is important if you're planning to use solely solar power, but if it's a choice between getting a small amount of power from your roof with inefficient panels or having nothing at all because you can't afford it, the cheaper ones certainly win.

However, this has gone off at a bit of a tangent from the OP. Regardless of what would be best in terms of solar cells, what is actually important is if they can do what they claim. There are an awful lot of claims about what the cost could be once they're available for general consumption, but not much about what they actually are now, and nothing whatsoever about the actual efficiency or reliability.

Also, as the article you quote points out, prices of existing solar cells have been plumetting for years, and are still going down. Even assuming these new ones are everything they claim, by the time they are actually available they may not have any advantage over existing ones.

 

[Schneibster]

Yeah, I have to concede that you're probably both right. Efficiency is important if you're planning to use solely solar power, but if it's a choice between getting a small amount of power from your roof with inefficient panels or having nothing at all because you can't afford it, the cheaper ones certainly win.

However, this has gone off at a bit of a tangent from the OP.

It's an important criterion.

Regardless of what would be best in terms of solar cells, what is actually important is if they can do what they claim.

They are shipping them, and have received first revenue. Either they're going to make a load of money or they're going to get sued out of existence. They announced the beginning of their first production run on the 18th of December. They've donated their third panel to the San Jose tech museum. It's not really a question any more, unless you think they're shipping fake product.

There are an awful lot of claims about what the cost could be once they're available for general consumption, but not much about what they actually are now,

You're right; this is a startup. I'm not surprised. It's low enough that a power company in East Germany has bought all their production for the next year.

and nothing whatsoever about the actual efficiency or reliability.

It's a new product. But it IS a product. If what they're claiming is even 75% true, I expect I'll be buying it within the year (if I can get my hands on it). I'll let you know (if I don't have to sign an NDA).

I strongly suggest surfing their web site a while longer. You might also want to note that they are in a 140,000 sqft facility in Silicon Valley, and a 500,000 sqft facility in Germany, and they're doing the manufacturing in those facilities. In addition, they're capitalized US$100 million which ain't chump change. They also have announced a $20 million contract with the US DOE.

This ain't somebody's backyard scam, it's an INDUSTRY. And right now, these guys own it.

Also, as the article you quote points out, prices of existing solar cells have been plumetting for years, and are still going down. Even assuming these new ones are everything they claim, by the time they are actually available they may not have any advantage over existing ones.

I think you'll find that they have considerable advantages, from what I'm reading on their web site. I'd really go check it out.

ETA: Worth mentioning I suppose that I drive by their factory in Silicon Valley on the way to work. It has a tendency to make it all a bit more real, if you know what I mean.

 

[Olowkow]

Just sent them an email (mailto:info@nanosolar.com) asking for technical information on their product. I'll pass along anything I get.

Not sure what they mean by this in their "contact us" section:

Note: Please do not inquire via phone; use email. We read every email we receive and follow up promptly if there is a match. Due to the quantity of inquiries we receive, we're afraid we cannot answer emails for which there is no match.

I have not run across very many $100,000,000 companies in my experience who don't want phone calls from prospective customers. Well, actually I can't think of one... What does "no match" mean?

 

[Schneibster]

Means everybody and their friggin' uncle George wants to talk to these people, not to mention probably a pretty notable collection of nutjobs, and they got business to do and more customers than they can handle already. Want some, get in line.

There's an opportunity there, and I bet someone with the bucks and the facilities jumps into the gap. Hope these guys don't lose their shirts because they got bidded out of the game by someone with better capitalization, because it wouldn't be the first time.

 

[Schneibster]

Let's put it this way: what's market saturation for solar panels when the next President is probably going to have a friendly Congress that's going to implement emission caps?



ETA: Ever see water on a duck's ***?

 

[Olowkow]

No response yet to my email to Nanosolar. Hmm.
I found this on Wiki concerning the claimed efficiency of the panels:

The company uses copper indium gallium diselenide—which can achieve up to 19.5% efficiency—to build their thin film solar cells. Nanosolar's solar cells are thought to have an efficiency of 13.95%.^WP (Bolded mine)

Xantrex makes some real killer DC to 220 VAC inverters, real sine wave at 60 Hz, with >90% efficiency, so that is very good.

One has to remember that the 100 watts/meter^2 is the max available, and hours of really good sunlight in most areas are not that many. The desert would be good.

 

[soylent]

Well, I think that at some point efficiency is precisely the point. Solar gives us about 1000 watts/square meter...maximum. That's the bottom line for 100% efficiency. Don't even think about a solar family car...well ok, those test cars that you have to lie down in to drive across the desert, fine.

http://en.wikipedia.org/wiki/Insolation

Approx. numbers:
If you only have 100 square meters on your roof, (10 x 10 meter roof), the maximum the sun can give you is about 100 kw. Not a lot! Cell efficiency of 50% (silicon crystalline) 50 kw, then conversion to AC 60 Hz, storage losses, maybe 30%, etc, etc. (Some of the best cells are 70%)

Solar quickly appears to me to be just a novelty for generating electricity at 10% efficiency and less.

Err. Why are you using more than a few hundred watts on a continual basis? Do you spend your spare time arc-welding or something? EV?

 

[Olowkow]

Err. Why are you using more than a few hundred watts on a continual basis? Do you spend your spare time arc-welding or something? EV?

Not really. A "few hundred" watts/hour doesn't get you very far unless you live pretty austerely. My last bill was around 500 kw/hrs for a month, non summer usage, and we really conserve, in my opinion. A month has 720 hours so figure around 1.5 kw per hour average roughly. More in summer. Plus, I would really want to heat and cook with electricity, not gas, if I went to the trouble of doing the solar project.

No, I don't need 100 kw, this was just to show what the limits are from a perfect system. One has to account for cloudy days, nighttime, lattitude, efficiency of the cells (Nanosolar is 14%), conversion (~90%), storage losses, etc.

There is no question it can be done. I just don't know how much area it would realistically take, given all the variables, to get enough to use, plus "selling back" to the power company to make it cost effective. Still figuring this out.

 

[soylent]

Not really. A "few hundred" watts/hour doesn't get you very far unless you live pretty austerely. My last bill was around 500 kw/hrs for a month, non summer usage, and we really conserve, in my opinion. A month has 720 hours so figure around 1.5 kw per hour average roughly. More in summer. Plus, I would really want to heat and cook with electricity, not gas, if I went to the trouble of doing the solar project.

1 W*hr = 3600 J is a unit for energy and 1 W = 1 J/s a unit for power(rate of energy consumption).

1 kW/hour = 1 kJ/(Second*Hour) = 3600 kJ/(Hour^2) looks like some kind of "energy-acceleration".

No, I don't need 100 kw, this was just to show what the limits are from a perfect system. One has to account for cloudy days, nighttime, lattitude, efficiency of the cells (Nanosolar is 14%), conversion (~90%), storage losses, etc.

The 500 kWh per month you are using is only ~700 W. If that's for 2 or more people you are using only a few hundred watts per person. If you assume the solar cells are operating at peak efficiency only 1/6th of the time and only 14% efficient, a hundred square meters gives you an average of 2.3 kW. Cheap enough to be cost effective is the big obstacle; the amount of space required is secondary. If you could print 2% efficient plastic film from reel to reel at 1$/m^2 I'd bet you everyone and their dog would shingle their roof with the stuff, building laws permitting.

(Two common culprits for excessive electricity consumption that are fairly cheap to fix: Are you using flourescent lighting for the fixtures that remain lit for long periods of time? Is your fridge/freezer distanced from the wall so that there is proper air circulation and it's radiator dusted off every once in a while(the hot reservoir should be as cold as possible for efficiency)? Is the fridge/freezer from the 90's or later(factor 2-3x improvements in efficiency since the 80's)?)

 

[Olowkow]

Here is an interesting site with a calculator for determining all the parameters.

http://findsolar.com/index.php?page=rightforme

 

[Matteo Martini]

1 W*hr = 3600 J is a unit for energy and 1 W = 1 J/s a unit for power(rate of energy consumption).

1 kW/hour = 1 kJ/(Second*Hour) = 3600 kJ/(Hour^2) looks like some kind of "energy-acceleration".
[..]

What about using nanosolar solar panels to power an electric car.

They claim that the cost/W will be down to less than 2USD.
A 10000W system will cost less than 20000USD.
You can recharge the battey of a Volt in 2 hours, apparently

 

[jimbob]

When you are talking about solar-powered cars, the cost per watt, whilst still important is going to be less important than the actual efficiencies.

Assume you have a petrol-powered car that can travel 50mpg at 50mph. The engine is thus using one gallon/hour

According to wikipedia the energy density in petrol is 34.8MJ/litre. There are 4.5 litres/gallon, so the car is using 4.5litres/hour.

This equates to 34.8x4.5=156.6MJ/hour. divide by 3600, and the car's power usage is 0.0435MW or 43.5kW.

Assuming that you would need similar levels of power for a solar-powered vehicle, and 20% efficient cell (higher than current efficency), then for every hour of driving, you would need 215sq metres of cell to be charged for an hour. (This area could be halved if you accept that every hour of driving requires two hours of charging).

Maybe such a scheme could work for commuting with a 2hr total commute and 8hr charging, you could recover a significant proportion of the energy whilst at work, in a sunny period....)

Caveat:

I have not looked at actual power requirements of electric cars, I have just been thinking these numbers through whilst I type, so electric-cars might have completely different requirements, but I doubt they would be too different for that level of accuracy.

 

[jimbob]

Matteo, looking at your 10,000W system, costing 20,000 USD, and assuming the efficiencies suggested above, that could have a driving:charging ratio of about 1:4, and use a significant area.

ETA, what would be required for the 2hr commute, and 8hr work scheme I suggested above

 

[Matteo Martini]

Matteo, looking at your 10,000W system, costing 20,000 USD, and assuming the efficiencies suggested above, that could have a driving:charging ratio of about 1:4, and use a significant area.

ETA, what would be required for the 2hr commute, and 8hr work scheme I suggested above

I think the problem is in the caveat you were talking about.
First we have to define what you mean by 20% efficiency, as they (Nanosolar) can have panels at 99 cents [50p] a watt, and I assume that meeans at net of efficiency, that is, that watt would be a usable one.
http://www.guardian.co.uk/environment/2007/dec/29/solarpower.renewableenergy
About the electric car, the Volt has a 16 kWh (58 MJ) lithium-ion battery plug-in system (link:http://en.wikipedia.org/wiki/Chevrolet_Volt#E-Flex_drivetrain).
To recharge a 16KWh battery with a 10KW system, it takes less than two hours.
About the size of the panels, and the area they need, I beg to notice that you can attach them almost everywhere, on the roof of your garden, over the external walls of your house, ..

 

[jimbob]

Of course it isn't just solar power:

7. Installed U.S. Wind Power Capacity Surged 45% In 2007
According To AWEA

The American Wind Energy Association (AWEA) announced that
the U.S. wind energy industry installed a record 5,244MW in
2007, expanding the nation’s total wind power
generating capacity by 45% in a single calendar year and
injecting an investment of over $9 billion into the
economy,. The new wind projects account for about 30% of the
entire new power-producing capacity added nationally in 2007
and will power the equivalent of 1.5 million American
households annually while strengthening the U.S. energy
supply.

And here is a (tech-heavy) article about improving thin-film polysilicon PV cells:

The Potential of Thin-Film Crystalline Silicon Solar Cells
If the efficiency and cost targets can be met, thin-film crystalline silicon solar cells have the potential to become a solid alternative to the bulk multicrystalline silicon solar cells that currently dominate the photovoltaics market.
(tech heavy)...

 

[jimbob]

Matteo, as you say, if you could find enough area, it might be economic for cars (1kw/m², incident light, => 200W/m² power Therefore for a 8on-2off (1:4) 16kWh charging regime, you could use a quarter of the area needed for 16kW. This would equate to 4kW. This would be 20 sq metres. So a house-roof system could probably supply a single car for a typical commute. At the petrol prices in the UK that could be attractive.

 

[Matteo Martini]

Matteo, as you say, if you could find enough area, it might be economic for cars (1kw/m², incident light, => 200W/m² power Therefore for a 8on-2off (1:4) 16kWh charging regime, you could use a quarter of the area needed for 16kW. This would equate to 4kW. This would be 20 sq metres. So a house-roof system could probably supply a single car for a typical commute. At the petrol prices in the UK that could be attractive.

May I ask you where did you take the data about how many square metrs of Nanosolar cells are required per kw?
That info is not written in their web site