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New Solar Panel Design Traps More Light
GoSun wrote in with an article about new solar panels that opens, "Sunlight has never really caught fire as a power source, mostly because generating electricity with solar cells is more expensive and less efficient than some conventional sources.
But a new solar panel unveiled this month by the Georgia Tech Research Institute hopes to brighten the future of the energy source." The new panels are able to produce sixty times the current of traditional models.
If you can get low $/watts with low efficiency that would be OK. Tile your house with the stuff, use it as the external covering for buildings.
That is one of the major problems with PV showcases like the Australian solar race. they push efficiency more than $/watts which is my the winning cars cost hundreds of thousands of dollars.
Engineering is the art of compromise.
Recall that most solar cells on the market acquire 10-20% of the energy that falls on them. Electrically, power is current times voltage. So this is a bogus claim. There's no point to claiming that the solar cell gets "60 times the current" while ignoring voltage (which dropped by an unspecified amount), and ignoring that there's only a theoretical factor of 5 to 10 possible improvement in power over current solar cells.
It's power that matters, not current.
The best solar cells today get about 13 watts / square foot. The toatl power available on a sunny day with near perpendicular light is 130-140 watts. So efficiency is near 10%. The best a new design can do is about 10-11 fold increase, not 60.
I've heard that the energy cost of making the panels is greater than the amount of power they generate in their lifetime. Don't know if that's true though, but it takes energy to make the panels, and they do wear out / break.
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You're talking about two different types of measurements for solar cells.
The statement "60x the current" has almost no relation to the maximum theoretical conversion of sunlight efficiency. It completely leaves out the voltage problems inherrant in these 3d designs. The total output measured in watts or VA would be somehwat more comparable to your "20 percent efficient".
Learn some math before you post.
) Human Kind Vs Human Creation
) It'd be interesting to see how many humans would survive to serve us.
If we had so many wind turbines that we were collecting enough power to run the world, would that not have some effect on the global wind patterns?
No. There is simply more power in the Earth's wind than we could harvest. Or, if you please, the current annual input of power into the atmosphere is greater than the total energy cost of human civilization, by a few orders of magnitude.
Remember: every single watt of solar power that reaches the ground winds up in the atmosphere as heat, the foundation of wind.
Also solar power cools the Earth's surface. Solar farms are envisioned as acres and acres of panels in the desert. That would turn a very hot spot into a very cold spot, changing the currents there, and thus affecting overall temperature distribution (ie, the wind).
If, and ONLY if, the solar panels were not only almost perfectly efficient, but also sucked energy from heat in the atmosphere.
Same sort of thing goes for tidal energy. If you collect enough, you are going to affect life in the ocean.
Tides are powered by the moon's gravity, bub. Sure you'll have an effect, but the tides are already affecting the moon's rotation.
There just ain't no free ride.
Depends on what you means as "free." Sure, the soup kitchen needs someone to pay for the soup, but the bums getting a hot meal get to enjoy someone else's largesse. Most of the power sources available to humanity work like that, including photovoltalic solar, fission, and hydroelectric.
They'd offer it to the power distribution and oil companies - probably on terms that guarantee a revenue stream well past the expiration of any patents on the technology. Why handle the messy details of dealing with the Great Unwashed one-on-one, when others who could be your customers already have the billing systems and the customer bases in place? And with unlimited clean near-free electicity to play with, the oil companies would find ways to produce hydrocarbons from sea water and atmospheric carbon dioxide pretty damn fast - they've got the storage and distribution expertise, and from a storage and usage perspective you have to admit that fossil hyrdocarbons are pretty damn convenient (if not particularly good for the environment). Synthetic hydrocarbon fuels would be carbon-neutral - the waste products are the same as the raw materials, water and carbon dioxide.
Large buildings and cities have much more of an effect on local wind patterns than wind farms do. "Global wind patterns" on the other hand occur in the atmosphere above any of this. You know, the atmosphere that extends up a few dozen miles, or many thousands of times higher than a wind turbine? Your claim is like saying a thin film of bacteria at the bottom of a river will affect the water current. Global warming, on the other hand, affects a large portion of the atmosphere and will likely cause changes in the wind patterns.
Solar panels don't cool the Earth's surface. Actually, it's the opposite as their albedo is lower than that of desert sand so more of the sun's energy is trapped instead of being reflected back into space. However, even if the entire southwestern US was covered with solar panels this effect on Earth's total albedo would be far less than the effect from the loss of the Northern polar ice cap (white ice suface being replaced by dark water). Beaming solar energy from space would probably be slightly worse than covering the deserts with solar panels, as this adds energy to the system that would otherwise not hit the Earth (most electricity is converted to heat when used).
Collecting tidal energy only affects the immediate surroundings of the facility. Certainly you should make sure to build this stuff where it doesn't cause harm. But it cannot change the effects of the tides anywhere else, as the tides are driven by gravity and Earth's rotation. These are things that can not be significantly affected by anything we do, unlike the atmosphere which we are affecting by continuing to emit huge quantities of CO2.
You should quit believing in the moronic strawmen concocted by people who oppose environmentally friendly technology. All of these are perfectly viable and a LOT better than coal.
Man, I wish we'd spent that Iraq War $TRILLION on solar research instead.
If we just got all its 212 possible oil barrels, that would have been $4.72 a barrel (enough to get 50M Americans to vote for it), but we probably won't get any of it now - unless we buy it from Iran.
That 750Pj could come from the Sun (at 1KW:m^2) into 4000K square miles (0.1% of the US total area) in 2.5 years. At 25% efficiency, that would be 10 years. We're already halfway through that alternate decade, we've only wasted huge amounts of energy (and life and limb), and are giving Iran the oil (to sell to us at $100 a barrel).
Investing $250M per square mile in American solar production would have actually secured America, especially from the oil terrorists, at home and abroad.
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make install -not war
The power convesion ratio is not really that important in itself. The only really important measure is $/watt.
Right, and the only thing that matters with hard drives is $/GB ratio? People don't size systems based purely on $ figures; required output weighs into the equation heavily, since systems usually pay themselves back pretty fast. It doesn't matter when you have a whole hillside or roof, but otherwise, size is important, and the more efficient a panel, (duh), the smaller. That matters for space availability and wind loads.
For example, it's not practical to put solar panels on the roof of a UPS truck; you could cover the entire roof, and even on a sunny day, you probably still wouldn't be able to supply enough energy to keep it going on a day's worth of deliveries. Increasing the efficiency matters here. Likewise for say, putting a solar panel on the back of a cell phone.
The other arena this helps in? Wind loads. If you have a residential system with several panels on a tracking frame, if the panels can be half the size, that means a cheaper frame and tracking system, and less of an eyesore in your back yard. Or, alternatively, twice as much power from the same frame.
What really matters is retail availability. I've been reading about advances in solar panel technology for years, and it's dripping into the consumer market like molasses. Why? Well, for one thing, oil companies are snapping up solar intellectual property and companies like crazy...
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Which is good to know, but you haven't answered his question. The question was about wind _patterns_, not whether we'll still have wind at all. Yes, the energy will still reach the ground, hot air will still be less dense than cold air, etc, but just like electric current, wind takes the path of minimum resistance so to speak.
Why are the patterns important? Because, for example, it only takes one relatively persistent current changing direction or moving somewhere else, to stop the carrying of dust to the amazon forest and triger an ecological catastrophe comparable only to the biblical flood.
Additionally, although unrelated to the original question, but related to the later "there just ain't no free ride", the wind farms have other problems. E.g., build enough of them, and you're whacking birds left and right. E.g., they tend to vibrate, which some animals and insects in the ground tend to not like much. E.g., they do cast a shadow, just like any other 3D object, so an area filled with those is pretty much an area where you can forget about growing anything, trees included.
Basically the problems are complex enough. Will we have a problem? Maybe, maybe not. I don't know. But just reducing it to, basically, "we'll still have wind" isn't answering it.
Here the straw man gets even more blatant. His question was about how it will affect _life_ in the ocean, _not_ who'll keep powering them, and _not_ how will they influence the _moon_.
Yes, they're powered by the moon, no doubt about that. How will it influence fish, algae, plankton, etc, in the coastal areas though? Because that's where those will be built. Will the shadow from a million generators kill enough photosynthesis there to choke the fish? Will the energy extracted from the water (remember, energy is never lost, it ultimately ends up heat) be enough to nuke one of the permanent currents? E.g., one permanent bogeyman about global warming is the possibility of stopping the gulf stream. Can we achieve the same by extracting enough energy at the source, where the tides are bigger and more fit to drive some generators in the water?
Notice that you can't really answer it as "there'll still be plenty of uncovered ocean", because the coastal ecosystems are often different enough. So they're not a substitute for each other.
Which is at best hand-waving. The implied question isn't whether there's a hidden cost at all, but whether it's a price we're willing to pay.
To give you an example of what's wrong with that hand-waving answer, let
A polar bear is a cartesian bear after a coordinate transform.