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See-Through Solar Is Tomorrow’s Threat to Oil

bloomberg.com

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Re: See-Through Solar Is Tomorrow’s Threat to Oil

#11

Post by experiment0 »

We are already struggling to make low cost solar panels that have a high efficiency using light absorbed from the visible spectrum (which accounts for most of the sun's spectral irradiation [1]).

Furthermore, you can't just have solar cells that absorb a wide range of the solar spectrum, there is an optimum band gap for these materials of around 1.34 eV [2].

This means that the most popular solar cells in development, namely CIGS and CdTe are already occupying the niche for maximum efficiency. The challenge now is finding new materials that are cheaper to make and show greater efficiencies whilst not relying on the use of rare earth/toxic elements.

(Hint: the real development in this area at the moment is hybrid perovskites [3])

Basically, this is irrelevant cruft.

[1] http://zebu.uoregon.edu/~imamura/122/images/solar_spectrum.p...

[2] http://en.wikipedia.org/wiki/Shockley%E2%80%93Queisser_limit

[3] http://www.nrel.gov/ncpv/images/efficiency_chart.jpg

(source: currently doing a PhD in a new photovoltaic materials)

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#13

Post by antr »

joss82 wrote: post #2

Oil is primarily used as fuel for transportation. How can I power my kilowatt car with these? How about flying a megawatt plane? This seems more like a milliwatt application. Probably nice and useful for phone, but not to replace oil. The title is misleading. What is the efficiency of this technology compared to the usual solar panels? We need terawatt-scale energy sources if we want to meet actual demand. How many s…

> Oil is primarily used as fuel for transportation.

The use of the word "oil" tends to include gas too (and in many cases coal) as the word the press many times doesn't use is hydrocarbons. Gas (be it natural gas, shale gas) is very much a source of electricity production, around one third of all gas is used for electricity... it's almost 100 in the case of coal.

> What is the efficiency of this technology compared to the usual solar panels?

It's mentioned in the video: traditional cells c. 30% vs 22%. A 1/3 loss in efficiency. But then, their use is more flexible.

> How many square kilometers of that glass do we need to install to meet that demand?

"Dividing the global yearly demand by 400 kW•h per square meter (198,721,800,000,000 / 400) and we arrive at 496,804,500,000 square meters or 496,805 square kilometers (191,817 square miles) as the area required to power the world with solar panels. This is roughly equal to the area of Spain. At first that sounds like a lot and it is. But we should put this in perspective." Source: http://landartgenerator.org/blagi/archives/127

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#14

Post by vilhelm_s »

explorigin wrote: post #6

Good solar cells are 40ish% efficient? I'm not a photonics engineer but I wonder how much of the total energy is in the visible range. Current solar cells are only cost-effective in limited scenarios, it's nice that these could go in more places but even if they reach cost parity with what we have today, the would be less power. We're going to need to see huge reductions in production cost or energy capture before th…

According to Wikipedia[1], "sunlight provides an irradiance of just over 1 kilowatt per square meter at sea level. Of this energy, 527 watts is infrared radiation, 445 watts is visible light, and 32 watts is ultraviolet radiation".

[1] https://en.wikipedia.org/wiki/Infrared#Natural_infrared

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#16

Post by TimothyFitz »

joshuaheard wrote: post #8

Only about half of oil production goes to energy and transportation. The other half goes to production of synthetic materials like plastic. Look around you, oil production is not going away any time soon.

The sources I could find say 4% is used for plastic and another 4% for the energy to make the plastic. Nowhere near 50%.

http://www.plasticoceans.net/the-facts/energy-consumption/

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#17

Post by higherpurpose »

joss82 wrote: post #2

Oil is primarily used as fuel for transportation. How can I power my kilowatt car with these? How about flying a megawatt plane? This seems more like a milliwatt application. Probably nice and useful for phone, but not to replace oil. The title is misleading. What is the efficiency of this technology compared to the usual solar panels? We need terawatt-scale energy sources if we want to meet actual demand. How many s…

> Oil is primarily used as fuel for transportation. How can I power my kilowatt car with these?

Easy. You build batteries using energy from solar panels, and then you charge them with energy from solar panels.

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#18

Post by jndetlefsen »

strommen wrote: post #9
ogrisel wrote: post #3

They don't speak about the angles (vertical windows vs horizontal roofs) and how much can this impact the energy efficiency in practice. Presumably it's good to have some vertical panels in a mix to produce energy in the late afternoon when the sun is low but I wonder if there is any quantified study available that would highlight whether or not this is worth the investment.

This isn't related to the clear solar panels from the article, but there's been significant research on this for traditional solar panels as well as solar concentrators. Bottom line is, the mix of panels makes sense for northern cities (e.g. Albany) but not middle (e.g. St. Louis) or southern (e.g. San Diego). There's a great writeup with links to the raw data at http://physics.ucsd.edu/do-the-math/2012/08/solar-data…

gives me a rough idea how big your world is.

Re: See-Through Solar Is Tomorrow’s Threat to Oil

#20

Post by higherpurpose »

experiment0 wrote: post #11

We are already struggling to make low cost solar panels that have a high efficiency using light absorbed from the visible spectrum (which accounts for most of the sun's spectral irradiation [1]). Furthermore, you can't just have solar cells that absorb a wide range of the solar spectrum, there is an optimum band gap for these materials of around 1.34 eV [2]. This means that the most popular solar cells in development…

As they say in the video, even if these are half as efficient as regular solar panels, you could still see them on other types of surfaces where current solar panels can't be used right now: think windows or smartphone screens.

We could also see them on large buildings or rich people's villas whose owners perhaps want to use energy from solar panels, but don't like the "look" of solar panels on those buildings. So then the choice becomes using this or using no other solar panels.

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