Photovoltaics do take energy to make and use toxic elements that can cause nasty pollution unless they’re contained. We knew that. But what I didn’t really bother to think about is that those same rare elements that are toxic are also, well, rare. We’re using them like they’re not rare. So . . . doh! . . . they’ll run out soon. Meaning soon. Times like “five years” and “2017” come out of the number-crunchers.
From New Scientist [1], reporting on Gordon, Bertram, and Graedel’s recent paper (abstract [2], pdf [3]).
It’s not just the world’s platinum that is being used up at an alarming rate. The same goes for many other rare metals such as indium, which is being consumed in unprecedented quantities for making LCDs for flat-screen TVs, and the tantalum needed to make compact electronic devices like cellphones. . . . Even reserves of such commonplace elements as zinc, copper, nickel . . . will run out in the not-too-distant future. . . . [T]he metal gallium, which along with indium is used to make indium gallium arsenide . . . is the semiconducting material at the heart of a new generation of solar cells . . . . Reserves of both metals are disputed, but . . . René Kleijn, a chemist at Leiden University in the Netherlands, . . . estimates gallium and indium will probably contribute to less than 1 per cent of all future solar cells – a limitation imposed purely by a lack of raw material.
Iridium is the material that blankets the planet in a thin layer, left over from the asteroid strike that bothered the dinosaurs. Some of the other elements are found in sand in nano-quantities. However, grinding up the whole planet to make solar panels doesn’t seem like a much better idea than turning it inside out to burn it.
Time to get extremely serious about organic (in the sense of carbon-based) photovoltaics [4]. It’s complicated, though. To begin with, organic molecules break down easily. And then, as Terry Pratchett might say, it’s quantum [5]. However, plants do it. Bacteria do it. You’re not going to tell me we’re stupider than plants, are you? (Don’t answer that.)
Technorati Tags: solar power, photovoltaic, PV, gallium, resources, shortage, Graedel
5 Comments To "Photovoltaics: (some more) depressing news"
#1 Comment By Uncle B On 09 Jul, 2008 @ 08:21
Humans are funny animals, we use digital in an analogue world, we use chemicals in a biologic world. We are evolving, and given enough time, we will go back to the future, where individual farming plots for survival will be highly organized in communal endeavors for survival. We are getting over the mechanical age, we will gain much from the information age, we are on the edge of the end of wars among mankind. We can control our population. We can educate the willing. We can destroy the dangerous detractors among us on an individual basis.We are at the threshold of a new era for mankind.
#2 Comment By mark On 06 Aug, 2008 @ 05:54
Let’s not forget that the internal combustion engine has required billions of dollars in R&D over the years. I suspect that the carburetor alone has needed more research that ALL the research spent so far on solar energy.
If the world had decided to forgo that engine because of the downside of all the unknowns that existed back in the 1890s, imagine where we would be today.
We’ve probably spent 1/100,000 on the R&D for a replacement to that energy model. Let’s not dwell so much on solutions we don’t have and instead work towards them.
#3 Comment By scott On 06 Aug, 2008 @ 09:35
Oh no!!! doom and gloom, doom and gloom, whatever will we do??? Oh that’s right we’ll develop some other method and go on about our lives. step outside, the sky isn’t falling chicken little.
#4 Comment By Leo On 18 Nov, 2008 @ 01:01
Perhaps, in future, landfills will prove to be goldmines, for they contain some of the rare elements we discarded in the past.
#5 Comment By spriggig On 28 Dec, 2008 @ 19:30
Solar energy was never THE answer to begin with. It’s AN answer, one of many–and not a particularly good one.
A better answer is geothermal energy, the 100% clean, base load, virtually inexhaustible energy source that sits no more than six miles beneath our feet. Look into it and start singing the praises of the REAL future energy source we’ll all depend on soon.