Re: OT: "The Amazing Randi", of all people, has swallowed the GW dogma:

In article <agt674tku5dgiv5qaguoor1057d43650eb@xxxxxxx>, John Larkin wrote:

Why do plants have so many leaves? And why do they use such a tiny
fraction of available solar energy?

Low utilization is probably for a reason similar to that for solar
cells. There is a peak utilization wavelength, where photons have
slightly more energy than some bandgap.
Wavelengths much longer than that don't get utilized at all, due to
photons having insufficient energy to push an electron from a lower energy
level to a higher energy level. When the wavelength is shorter, photon
energy in excess of that used to push an electron from lower energy level
to higher energy level becomes heat. So a blue photon only gives a plant
as much chemical energy as a red one, even though a blue photon has more
energy than a red one.

Plants have their primary utilization peak around 660 nm (red peak of
chlorophyll A). Accessory pigments and blue chlorophyll absorptions
absorb wavelengths of a variety of shorter wavelengths and transfer the
energy to the main chlorophyll A process. But most plants don't utilize
green light well, because the chlorophylls and the main accessory
pigments mainly utilize red and blue.

So wavelengths longer than about 700 nm (almost half of average
daylight) don't get utilized, green wavelengths are not utilized well, and
blue wavelengths are utilized but with some significant loss. UV is
utilized less than blue is, and with even greater loss.

- Don Klipstein (don@xxxxxxxxx)
.

Relevant Pages

  • Re: OT: "The Amazing Randi", of all people, has swallowed the GW dogma:
    ... Low utilization is probably for a reason similar to that for solar ... slightly more energy than some bandgap. ... Wavelengths much longer than that don't get utilized at all, ... current CO2 levels; future, higher CO2 levels, and higher ...
    (sci.electronics.design)
  • Re: OT: "The Amazing Randi", of all people, has swallowed the GW dogma:
    ... Low utilization is probably for a reason similar to that for solar ... slightly more energy than some bandgap. ... Wavelengths much longer than that don't get utilized at all, ... photon ...
    (sci.electronics.design)
  • Re: Photon Energy...Huh?
    ... > energy without aquiring mass?? ... The energy of a photon is hv, ... Or perhaps 1000 wavelengths? ... think the solution has to lie in the concept of dual spacetimes where a ...
    (sci.physics)
  • Re: Limitation of wavelength
    ... >I'm not asking if there is waves beyond gamma rays, but more like, how small ... >can wavelengths get? ... If a photon has no size, ... practical limit that the energy of the photon cannot exceed the total ...
    (sci.physics)
  • Re: OT: "The Amazing Randi", of all people, has swallowed the GW dogma:
    ... Low utilization is probably for a reason similar to that for solar ... slightly more energy than some bandgap. ... Wavelengths much longer than that don't get utilized at all, ... photon ...
    (sci.electronics.design)