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New Record For Solar Cell Power Efficiency
mdsolar writes "Renewable Energy Access is reporting that a consortium led by researchers at the University of Delaware has achieved 42.8% efficiency with a silicon solar cell. The method uses lower concentration (factor of 20 magnification) than the previous record holder (40.7% efficiency) so that it may have a broader range of applications, since tolerances for pointing the device will be larger. They are now partnering with DuPont to build engineering and manufacturing prototypes. They expect to be in production in 2010. On a roof, such cells would require less than half the surface area to produce the same amount of power as today's standard solar panels, which have an efficiency of about 17%."
OK, but how much of a typical house's power would that supply? (I realize this depends on location and time of year.)
Or how many panels would it take to give you a daily, full recharge of a plug-in hybrid in, say, Los Angeles? (Imagine that that would do for LA's smog.)
that renewable sources of energy are a good thing.
why?
because my HOA (home owners association) does not permit them. As such it would take State or local laws to override the HOA; because in many States the HOA rules have strong legal backing at the State level.
This is akin to the problems satellite TV faced in many locales. There were numerous ordinaces, both at the HOA and local level which blocked satellite dishes. Even the small ones we are accustomed to today were blocked. It took a Federal Law to end that restriction. Unfortunately its going to take another such law to allow many of us to use renewable energy. Hell, I cannot even get rain barrels approved even though they would not be visible from the street.
* Winners compare their achievements to their goals, losers compare theirs to that of others.
The real problem with solar power is not getting more watts per square inch; it's getting more watts per dollar. From what I hear, high grade silicon is prohibitively expensive. It takes more than 3 years to pay back your monetary investment. This information is probably based upon old panels though.
These new panels may produce twice the energy, but is there any chance that they cost less than twice the dollars? What is the limiting factor in solar panel costs?
I've heard that some people are working on polymer solar panels, this would seem to deal with the dependence on expensive silicon...
One thing I have always wondered though: given the fairly large surface area of the turbine blades, would it be possible to add a photosensitive material and pull a bit of power from the sun too? Probably not terribly practical at the moment, but I seem to recall reading, probably on
Lose: misplace or fail || Loose: not bound together
What matters to me: Do those new cells finally "produce" more energy during their life than they required during manufactoring?
These are *VERY* wise words!
Instead of making more money, people could work less. Instead of buying all sorts of shit, people could do much cleaner things such as talking, writing, riding a bike, going to a brothel, taking a walk, singing, playing a part on a play, painting, fighting (if not pushed too far it is not necessarily bad for some people...).
It is way too simplistic to say that there is a law of nature that says we will end up using every resource available. We are supposed to be rational beings even if we often do stupid things. One of the things of being rational (or partly rational) is that we can choose what we do. We don't simply answer any call of the wild (even if there is such a thing).
We are changing from a production society to a consumer one. We are becoming a bunch of morons that just sit and receive stuff. Not very different from the Eloi in H. G. Wells' The Time Machine. I don't think just consuming is satisfying enough. It is much easier (and faster) just to watch a movie than it is to tell a story and we end up watching 10 movies. Maybe a little boredom is good for creativity. It certainly is much cleaner than riding a car 100 km to do anything "new".
I razzed New Mexico Governor Bill Richardson on my blog yesterday saying he is trying to keep the southerneastern US off solar so he can build a huge New Mexican Solar Power Monopoly to supply them: http://mdsolar.blogspot.com/2007/07/new-mexicans-c onspire.html(tinfoil hat warning). One of the projects linked there aims to do just this, havesting the heat generated at the panels for building heating. Engulf and Devour, that's his motto.s -selling-solar.html
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Register your home for solar power; fixed competitive rates for up to 25 years: http://mdsolar.blogspot.com/2007/01/slashdot-user
We don't even need a true power on off switch that has to be flipped manually. What we need is a remote power switch that cuts main power, and a small, rechargeable battery cell that can respond to the remote and re-activate main power. A tiny battery and a capacitor to have enough juice to throw a 2.5 volt magnetic switch would add about $1 in manufacturing costs to home theater devices, but save dozens per year in electric fees per home for "trickle" devices. All network devices should support Wake on LAN, but unfortunately, most don't (or do, but people don't know what that means or how to use it).
Unfortunately, a lot of devices are always on, like DVRs, game stations with online access, and more. They do a lot of work at night updating databases, downloading new content, etc, and simply have to remain on. The fact that an XBox 360 doesn't spin down the graphic system power and down clock it's CPUs is a design issue we can change. An Apple TV box uses less than 20 watts when "asleep" and that included downloading content over wireless. Why can't the XBox and PS3 do that? They could even drop into an even lower power state when idle, spin down the HDD, and only "wake up" every 90 minutes or so to check for content without spinning the drive up again unless it needs to.
Unfortunately, there are even more devices we can't really do anything about that are the real sappers in the house. The cable modem, wireless router/firewall, VoIP modem, second access point to cover downstairs, possibly an extra switch to add more than 4 wired devices (I have 7), and base station and answering machine for wireless phones. That's just the network. Now add the garage door opener, automatic sprinkler system, home alarm and smoke detectors (most run on house power and rechargeable batteries now), safety lights in your halls and bathrooms (night lights), and several clocks.
I work for a computer systems manufacturer. We've got a meter (magnetic ring type thing) at the office that encircles a power line and displays the power being used by the device. We have it so we can document in our white papers the power consumption of our devices. I brought it home and played with it a few months ago when having a forum argument with another individual on this. My 27" tube TV used about 2 watts when sleeping. My 37" LCD used less than 1. My PS2 used no power (but the transformer was using 2 watts). My cable box used 12 watts when asleep, DVR used between 20 and 50 depending on what it was doing when asleep. What surprised me was the coffee pot was using 3 watts when off (it has a tiny built in clock). The 2 alarm clocks we have each use 5 watts. Adding up all my idle devices I was just over 220Watts in use! 10% of that was in scent plug-ins around the house and night lights, about 20% was in our cable boxes alone. 25% was in devices I can't turn off, like the garage opener, stove clock, built in microwave, etc. Another 20% was in my home theater equipment (amp, dvd, vcr, and TVs). There were some other random devices around as well, not including my network setup...
After finding this out, I installed a "step on" power extension (like people use under the Christmas tree) in line between the wall and home theater, so I can press one switch at night to turn off all the device in the HT setup (except the DVR which has to stay pugged in all the time per the cable company or they'll void the warranty on the device). I threw out all the scent plug-ins in favor of passively diffused oils and popuri. I changed the few night lights we had out for LCD versions. I now have a programmable timer power strip in the computer room that I have 2 laptops, a small TV, a printer and a network switch hooked up to. Each night at 11:00PM the adapter cuts power to the laptops (which hibernate automatically after 15 minutes when on battery), my printers, the switch they're connected to, and the TV and cable box in there. My HTPC now uses sleep mode with Wake on Lan to save power and automatically shuts down and powers
There is no contest in life for which the unprepared have the advantage.
And while you've raised the issue, shall we discuss political meddling in the opposite direction (cough EPA report cough)? Why are long term trends not taken into account in these reports, for example. They look at century time scales, but not longer, because (despite what you say) predictions are very hard to do for longer timescales, especially given the uncertainty in what humans will be doing in terms of atmospheric emissions and land use changes. Remember, climate physics is not the only input into climate prediction; you need projections of human activity as well. (See here.) Winter is coming, and in 10.000 years we'll be in an ice age. The start of the downward trend in average temperatures is imminent (which means anywhere between now and 1.000 years)... It is far from established when the next ice age cycle is going to start, and there are some who claim that due to patterns in orbital dynamics, the current interglacial could be exceptionally long (as long as 50,000 years). (See here.) Perhaps that is why the IPCC report does not look any further than the year 2100 Perhaps it is, as I said, hard to project much more than a century or two in advance. the scary hockeystick curve will flatten out after that year, and if you look even further it will drop The current rate of warming far exceeds the natural rate of cooling during glaciation. That rate of warming will eventually level off, but it's not going to be outweighed by glaciation any time in the next few centuries.
It is true that eventually we will enter a new ice age, regardless of global warming, but no one is "ignoring" this fact. It's just farther off into the future; right now, the warming is what we have to deal with. If warming is a problem, you can't just ignore it because someday it will be cooler. Our distant descendants (if any) may even be grateful for the extra CO2 we have released, since it might make the next ice age a little less severe. If that turns out to be the case, it's better to release the CO2 then, rather than now, when we don't need it. As we have seen already, it's far easier to raise the temperature quickly than it is to cool it, having to do with the ease in emitting CO2 as a byproduct of civilization and with the long residence time of CO2 in the atmosphere.