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World record solar cell with 44.7% efficiency

phys.org

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Re: World record solar cell with 44.7% efficiency

#81

Post by jules »

twelvechairs wrote: post #71
scythe wrote: post #55

Earlier quoted context omitted.

The cost of solar today is dominated not by panels, but by conversion and installation. Typical solar panels these days are about $0.80/watt, but installation hovers around $3/watt. The former is competitive with fossil fuels; the latter is not. So the efficiency gain is actually very good, because current panels are on average 14% (iirc) efficient. If that can be raised to 42% the installation drops to $1, for examp…

where are these figures from? seems incredible for installation to be substantially more than the panels in my rxperience. unless 'installation' is including the price of other fixed components (batteries and inverter). Also 1/3 size does not mean 1/3 installation costs. lots of the underlying figures don't change (truck call out, overhead, installation of other elements, cost of permits, electrical wiring, etc).

The point is that you still install the same amount of panels, but now you get three times as many watts. Since the other underlying figures don't change, the installation cost is 1/3 per watt.

Re: World record solar cell with 44.7% efficiency

#82

Post by samolang »

dredmorbius wrote: post #73

For those wondering about the significance of this announcement: As several people have noted, what matters for solar PV isn't efficiency but cost per Watt . The maximum available energy is 1W/meter^2 at ground. Single-layer PV efficiency is on the order of about 40%. Mutliple-layer cells can reach a maximum of around 80%. Even with existing efficiencies, the land space necessary to dedicate to solar power for all el…

*the price of solar photovoltaic modules tends to drop 20% for every doubling of cumulative shipped volume

https://en.wikipedia.org/wiki/Swanson's_law

Re: World record solar cell with 44.7% efficiency

#83

Post by kelvin0 »

dredmorbius wrote: post #73

For those wondering about the significance of this announcement: As several people have noted, what matters for solar PV isn't efficiency but cost per Watt . The maximum available energy is 1W/meter^2 at ground. Single-layer PV efficiency is on the order of about 40%. Mutliple-layer cells can reach a maximum of around 80%. Even with existing efficiencies, the land space necessary to dedicate to solar power for all el…

I wonder if electrolysis and storage of Hydrogen would be a viable 'storage' method? Of course, the problem then might be the hazards associated with containing such a 'bomb'.

Re: World record solar cell with 44.7% efficiency

#84

Post by Symmetry »

dgreensp wrote: post #39

So when does solar power become cheap and efficient enough that it's a real game changer? It seems like the numbers have gotten a lot better in recent years, at least in terms of efficiency.

There won't be any single tipping point. Solar works better in equatorial countries than in northern ones like England. Solar doesn't gain in efficiency from centralization like turbine based power generation does, so you'd expect less dense countries to use it first. And the more solar you use the less valuable solar is, since solar output varies with time of day and weather and energy storage is relatively expensive.

But solar efficiency is increasing exponentially and cost is decreasing exponentially. So I expect solar to be ever more significant, limited in the long run by tradeoffs between power storage and non-solar generation, though the line there is sort of fuzzy.

Re: World record solar cell with 44.7% efficiency

#85

Post by moocowduckquack »

JoeAltmaier wrote: post #80
dpatru wrote: post #54

Earlier quoted context omitted.

> If that isn't a reason to be investing in Space, I don't know what is. To justify government research, the results need to be compared to the alternative. Had NASA scientists not been working for the government, they would have been working for private companies engaged doing useful work. The Soviet Union had similar resources to the US, yet their research budget was spent wholly by government, whereas a large port…

The real reason is, all the solar cell numbers are fake. Its dark around here (and everywhere else) an average of 50% of the time. In space, its bright (brighter than on the ground) around 90% of the time. Terrestrial solar cells MUST account for this when comparing efficiencies. So this new cell is 23% efficient, versus 46% if deployed orbitally, before accounting for the increased solar intensity in space. Elon Mus…

So this new cell is 23% efficient, versus 46% if deployed orbitally

That isn't how you calculate conversion efficiency. If there is no input to convert, you don't count that as a conversion loss.

Re: World record solar cell with 44.7% efficiency

#86

Post by moocowduckquack »

ars wrote: post #46
bsullivan01 wrote: post #37

Earlier quoted context omitted.

Interesting. Considering that solar is essentially "free" after you buy the equipment, something like Moore's Law can be applied to the price of solar panels or their longevity. We got plenty of space in our roofs :-)

Less space means less installation costs, and it means less raw materials. Silicon is OK, but some of the other stuff doesn't exist on earth in sufficient quantity to use solar energy in quantity.

I doubt we are going to run out of either phosphorous or boron.

Re: World record solar cell with 44.7% efficiency

#87

Post by scythe »

twelvechairs wrote: post #71
scythe wrote: post #55

Earlier quoted context omitted.

The cost of solar today is dominated not by panels, but by conversion and installation. Typical solar panels these days are about $0.80/watt, but installation hovers around $3/watt. The former is competitive with fossil fuels; the latter is not. So the efficiency gain is actually very good, because current panels are on average 14% (iirc) efficient. If that can be raised to 42% the installation drops to $1, for examp…

where are these figures from? seems incredible for installation to be substantially more than the panels in my rxperience. unless 'installation' is including the price of other fixed components (batteries and inverter). Also 1/3 size does not mean 1/3 installation costs. lots of the underlying figures don't change (truck call out, overhead, installation of other elements, cost of permits, electrical wiring, etc).

It's a rather common thread, I'm having a bit of trouble finding an authoritative source but let's look around:

http://michaelbluejay.com/electricity/solar.html

>Incidentally, naked solar panels currently (2013) go for about $1 per watt ($1000 per kWp), installation costs are about $4 per watt, for a total installed cost of about $5 per watt, without batteries.

http://newscenter.lbl.gov/news-releases/2012/11/27/the-insta...

>average non-module costs for residential and commercial systems declined by roughly 30 percent from 1998 to 2011, but have not declined as rapidly as module prices in recent years. As a result, non-module costs now represent a sizable fraction of the installed price of PV systems

>the median installed price of PV systems installed in 2011 was $6.10 per watt

http://en.wikipedia.org/wiki/Solar_panel#Price

>in 2012 it was estimated that the quantity cost per watt was about $0.60

http://www.wholesalesolar.com/bulk-solar-panels-by-the-palle...

>Price per watt: $0.84

So if anything, I might be lowballing it. I was thinking in terms of tripling wattage for the same amount of effort, (which makes sense for commercial PV) rather than thirding effort for the same wattage (which makes more sense at home), so your secondary point is valid. If at-home PV takes off, it might be a good time to be an electrician.

Re: World record solar cell with 44.7% efficiency

#88

Post by scythe »

kyberias wrote: post #67
nazgulnarsil wrote: post #31

Earlier quoted context omitted.

ERROR BARS DO NOT WORK THAT WAY

Care to elaborate?

The +/- 3.1% is relative to the efficiency. The way to read it is: 0.447 +/- 3.1%, where now it's more obvious that it translates to more like 0.447 +/- 0.014.

Re: World record solar cell with 44.7% efficiency

#89

Post by mchannon »

kelvin0 wrote: post #83
dredmorbius wrote: post #73

For those wondering about the significance of this announcement: As several people have noted, what matters for solar PV isn't efficiency but cost per Watt . The maximum available energy is 1W/meter^2 at ground. Single-layer PV efficiency is on the order of about 40%. Mutliple-layer cells can reach a maximum of around 80%. Even with existing efficiencies, the land space necessary to dedicate to solar power for all el…

I wonder if electrolysis and storage of Hydrogen would be a viable 'storage' method? Of course, the problem then might be the hazards associated with containing such a 'bomb'.

In practice it's pretty bad; Hydrogen, even compressed, takes up a large amount of volume. A 10 gallon tank stores about 1.5 gge of compressed H2.

The energy to compress H2 is again as much as it takes to create H2, and you don't get that energy back when you burn it (combustion perhaps 30% efficient).

An electric battery returns a far higher percentage of the power in, and is far simpler and safer.

H2's dangers are mitigated by its limited energy density. Most of the people on the Hindenburg survived.

Re: World record solar cell with 44.7% efficiency

#90

Post by Roboprog »

forgottenpaswrd wrote: post #78
dredmorbius wrote: post #73

For those wondering about the significance of this announcement: As several people have noted, what matters for solar PV isn't efficiency but cost per Watt . The maximum available energy is 1W/meter^2 at ground. Single-layer PV efficiency is on the order of about 40%. Mutliple-layer cells can reach a maximum of around 80%. Even with existing efficiencies, the land space necessary to dedicate to solar power for all el…

"The maximum available energy is 1W/meter^2 at ground" Where are you from, Britain? http://en.wikipedia.org/wiki/Sunlight ""sunshine duration" to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per meter" "The total amount of energy received at ground level from the sun at the zenith is 1004 watts per square meter" This depends on altitude of course, the max…

I assumed he meant "1 kW" and missed the k.
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