Actually, you don't really need to focus sunlight if it's sufficiently-unhindered (not much things stopping it, ILMT): see, "raw" solar wind's actually pretty powerful, it's just that most of the radiation's been redirected by the planet's magnetosphere first, then is filtered by the radiation belt, then the Ozone layer, and finally the atmosphere itself. So the "sunlight" you need to "focus" with your magnifying lens? Without these safety filters, you'll find our planet actually being like Mercury, being stripped by Solar Wind daily.
How does this relate to Solar Beam
? In theory, with sufficient charge, a Pokemon could replicate the "raw" solar wind, a power capable of turning oceans into dry wastelands. Even a few seconds of the pure stuff can be deadly, but considering how filtered sunlight is (as we know it), it makes sense how there's a need to charge up. Sunny Day is a move that thins out one of these filters, making the solar wind encounter less resistance, and thus less need to charge.
But the bigger question would be how to emit this beam, yes? At this realm, I can only speculate, but a quick look at Bulbapedia's anime entry into the how the move's implemented means it's not necessarily from the mouth:
Bulbasaur-line emits from the same place it absorbs: its bulb/flower
Sunflora emits it from the same place it absorbs: it's FACE
Meganium emits it at the apex of the place it absorbs: from the flowers on it's neck, then to it's mouth
Roselia emits it from its hands, which is also used to absorb
Sceptile absorbs from its tail, then emits from its mouth
At charge-up stage (lasting a full combat round 3-10 seconds), a combination of Hyperdrived-chlorophyll (chlorophyll stimulated by special hormones/enzymes to absorb light so efficiently it might as well be a radiation black hole), then my Mitochondria-overdrive hypothesis churning vast amounts of ATP to absorb said energy (hell, maybe the Mitochondria might have to be triggered by more hormones to produce a different energy-molecule than ATP to cater to such energy demands);
at firing-stage (lasting depending on how much energy was stored), the ATP is redirected to a bio-focal point, where they are broken down and the energy released in one huge solar "burst" (akin to a solar flare on the sun's surface), the energy redirected efficiently at the opponent by powerful, but brief magnetic forces created near the bio-focal point (like a flashlight redirecting light through mirrors).
This is just my educated guess. Take it with a gulp of salt, eh?
quick edit: there's also another way that various Pokemon use, by gathering the sunlight at an external focal point to form a glowing orb, where it is then redirected into a beam of energy at an opponent. My guess is they skip the Hyperdrive-Chlorophyll and Mitochondria-overdrive stages and quickly go through magnetic containment, which is then released at the opponent. But it's beyond my scope as to how this would be more efficient, considering the space around the orb isn't turned into a psuedo-black hole during the charge-up phase.
edited 9th Aug '13 5:44:42 PM by J.N.L.J.
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