Curious as to what others think about this idea. More techno than chemistry but I guess it fits here.
It
says more about trees and plants than it does about commercial solar arrays. The result itself is hardly surprising, since you're comparing the
performance of a fixed angular orientation to a distribution of orientations. The conditions themselves are variable, as the two arrays were in shade
for at least part of the experiment (see photo), and the experiments were carried out for long enough that the declination of the sun changed.
What it doesn't speak to is the economy of fixed collectors in absence of shade. This includes many rooftops and all dedicate solar plant facilities.
It also doesn't compare different leaf-branch arrangements, which would be rather interesting. There's no comparison of different branch length ratios
or bud angular orientations. It's typical that evolution finds optima. The question then becomes "which optimum?".IrC - 22-8-2011 at 09:00
I was impressed that people who think outside the box still exist in the latest generation. Leaves turning to track is a factor which should be
considered. In the 80's in Phoenix I used an Opamp and two CDS cells to run a servo motor with limit switches to make a roof mounted array track the
sun. Had to add a circuit to power down the servo below a minimum light level to stop it 'hunting' at night.gutter_ca - 22-8-2011 at 10:29
"How did this confused science project became international news?"
Maybe because like me, they had given up all hope on this younger generation of London burning entitlement demanding brainwashed lemmings. We saw hope
in this one and decided he should be pointed out, looked up to by his peers. The kid is 13 so if he has omissions in his work so what. Leave it alone
and stop picking and demonizing the poor kid like a pack of wild jackals. Which by the way is the way I see people today. Being almost 60 I remember a
brighter day. What is a blog. Is it not some person who decided to appoint themselves whiner and complainer in chief. So a kid has no chance today
unless he can make it past a peer review group without credentials of their own. No question marks I really do not care for answers. I am of the old
school who believe every possible positive thing should be done to reinforce a person in the hopes they will grow and get better over time.
The main problem with the internet is around 7 billion people with mikes who all loudly proclaim they have a good bead on things.
I should add, look at the quote above taken from that link. If you can see the improper use of English in it and therefore the illiteracy of the
person writing that page then there may be hope for you yet. Maybe they should not cast stones. The proper use of the word should be 'become' not
'became' due to the structure of the sentence. Very irritating to me when someone themselves flawed chooses to nit pick imperfection in others.
I see this abortion of proper language skills in every news report and nearly every web page I look at these days.
[Edited on 8-22-2011 by IrC]White Yeti - 3-9-2011 at 05:44
Very strange project.
The thing I found most ignorant is that he used a flat panel solar array that didn't even have a tracking system. As we all know, a solar array must
always be completely perpendicular to the sun's rays, or else, you are wasting solar energy. One exception can be made if you live at or near the
equator. Instead of finding a way to use more cells to generate less power, he should have rather developed a tracking device that is cheaper and
simpler than the ones that operate via computer control.
Also another suspicious subtlety is that if you look at the angle at which the flat panel is oriented towards the sun, it is angled noticeably lower
than the position at which it would be perpendicular to the sun's rays.
So his control gave him a false sense of accomplishment. Trees cannot track the sun throughout the day, that is why they need to grow in a spiral
pattern. But industrial solar farms can, and will, track the sun throughout the day.
As a side-note, can anyone explain why this tree does not adopt a spiral growth pattern like all the other trees?
Perhaps it chooses to be different....magnus454 - 3-9-2011 at 07:36
Besides using newer photovoltaic technologies (dyes, and other materials) the only thing I could think of would be to cool the solar panels down to a
lower temperature, since they get pretty hot in full sun, this might increase your output some, You could always use the worlds blackest paint
(NASA,Aerospace polyurethane) and paint it onto a giant iron/constantan (type j) thermocouple as a solar thermal power source.White Yeti - 3-9-2011 at 07:56
It's funny you should mention that magnus454. Many say that a solar cell works better at lower temperatures, but why is that? Usually, the electrical
resistance of a wire increases when temperature rises.
But semiconductors are different, they actually conduct electricity better at higher temperatures because more electrons get promoted to the
conduction band. So there must be a trade-off somewhere.
Any ideas?aliced25 - 3-9-2011 at 15:03
If they could be screen printed (complete with contacts) and laid on flat ground in sheets 100m wide and several km long, then they'd be a decent
alternative power source here (there is tens of thousands of square km of dried salt lakes & desert) that are predominantly flat and unused for
agriculture. That is where the research is going here at present, there are also dyes (like luminol - used in yellow highlighters) that downshift UV
to yellow-green light allowing it to be utilized by PV Cells.
