Solar Tree Bears Fruit 106
Hugh Pickens writes "A prototype solar tree that recently went on display on a busy street in Vienna, Austria has passed a key test by providing light during the night-time even when the sun had been blocked by clouds for four days in a row. The branches of the solar tree were decorated with 10 solar lamps, each one powered by 36 solar cells. The tree included rechargeable batteries and electronic systems to measure the amount of light in the atmosphere and trigger the solar lamps to go on. 'Not just trees but other objects could be decorated with solar cells and so keep streets well lit at night time,' said Christina Werner from Cultural Project Management. Google uses a similar concept to light their parking lots with 3,000 solar panels that provide up to 10 percent of the Googleplex's power demand. We discussed Google's solar initiative last year."
The question is... (Score:3, Insightful)
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Well, looking at the photo, it's certainly prettier to look at than most street lamps. Just a bit of a futuristic, more organic look. I like it. And it certainly gets more publicity than bolting some panels on top of an existing lamp. Besides, this is a prototype, so maybe you'll get your wish and the actual approach taken by city councils will be to adapt existing lights.
We should never give up our appreciation for elegance.
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thats a really good point heh.
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Thanks and good of you to say so. Sadly
Re:The question is... (Score:5, Interesting)
How much non-renewable energy does it take to produce each solar tree
If that were the only energy concern, then you'd have a point. It probably does take more energy in the beginning to produce it. However, the better (and more relevant) measure is total energy consumpption over its lifespan. That is, compare the manufacturing energy + energy use from grid + maintenance (replacement bulbs, etc.) over its projected lifepan to a standard lighting system. If it turns out that the overall energy used is less than that of a standard one, you come out ahead. You could also do cost analysis, but any pilot system has a much higher cost than production systems.
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Since early October, only in Austria. Here is a link that tells you all about it. [renewablee...access.com]
In other news: RTFA.
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Re:The question is... (Score:5, Insightful)
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The "daylight measuring electronics" are bone simple, it's just a simple comparator chip (costing pennies) that compares a reference voltage (taken from the bat
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Re:The real question is... (Score:1, Funny)
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I presume you meant to try to revive the tired old myth that solar cells take more energy to manufacture than they produce over their lifetime?
Simple argumentum ad absurdum:
We (the continental US, but this applies to most places on Earth) receive 5.5 useful sunlight hours per day, on average.
Modern solar panels have an effective lifespan of at least 20 years.
That gives 40k hours over which a given panel can repay its initial cost
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We (the continental US, but this applies to most places on Earth) receive 5.5 useful sunlight hours per day, on average.
On average, maybe, but it doesn't make NY or Washington get as much sun as Texas. You'll get a better ROI the farther south you live and the less cloudy the atmosphere is.
Modern solar panels have an effective lifespan of at least 20 years.
Is that taking into account hail storms and other forms of damage that happen in non-ideal conditions? I've seen hail leave dents in cars, I'd imagine that would be pretty devastating to a solar panel array. I'd imagine they'd also be pretty useless when they're covered with snow during the winter.
The cheapest commercially-manufactured home solar panels currently cost $3 per Watt.
Is that just the panel cost? If so, tha
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The argument I made applies to the myth that solar cells take more energy to create than they will ever produce. While you make a few good points, they don't really apply to supporting or refuting my argument.
On average, maybe, but it doesn't make NY or Washington get as much sun as Texas.
True... but you could also look at the flipside of that - In a Southern state, you'd do considerably better than the average.
Is that taking into account hail storms and other forms
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Didn't anyone see that indestructible monitor a few days ago with the crystal screen? Okay, it's not actually indestructible but it's a tr
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Good, REALIABLE, long-lasting solar cells run more like $6/watt, I think.
Ferretman
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First, see my other response in this thread. [slashdot.org]
Second, do you have a refridgerator? AC or heat for a significant part of the year? A home file server or even just an always-on DVR? Anyone home during even a portion of normal daylight hours, such as a child after school, or yourself on weekends?
I originally posted on this topic to refute an all-too-
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Or, say, your own employer during the hours you work - Thus we have net (or "reverse") metering [wikipedia.org] to let you do exactly what you suggest.
So if storage isn't really an issue, then solar power doesn't buy me a thing.
You don't own a refrigerator? That alone quite likely accounts for a third to half of your electric bill, p
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We (the continental US, but this applies to most places on Earth) receive 5.5 useful sunlight hours per day, on average.
I heard on a radio show (naked scientists podcast) a calculation involving installing solar panels in Saharan Africa and how that could provide enough energy to power Europe. it was a bit of a naive calculation (what happens at night etc), but it made a good point. I wonder if there is a business model somewhere where temperate countries could buy electricity from sunny countries.
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Side note: You could use only renewable energy to make the device but then it would cost more and therefore decrease its benefit. There is a break even point were renewable energy is cheaper than fossil or nuclear energy, but we ar
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I think that every power source uses a lot of energy, renewable or not.
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its look is like an anemone quite alien an almost Martian chronicles feel to it. googles bus shelter designs are not as interesting to look at.
cost to make them may be quite high, however with 10% of European electricity production going into street lighting in europe the potential reduction in carbon emissions is significant.
Retro fitting just the LED lamps to existing street lighting could be power saving in itself. The solar panels
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Or you could just stop cutting down every tree in sight...
Solar Electric Baobab Tree (Score:4, Insightful)
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On top of that, we get plenty of rain in these regions (Austria/Western Europe), so there's no need for irrigation. In places where they do need irrigation, there's not much rain to collect, methinks
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Re:Solar Electric Baobab Tree (Score:4, Insightful)
Firstly, the water that reaches the soil when it's raining mostly flows over the surface and into drains. If it were stored and released slowly, it would be more effective at watering the plants since it would have time to penetrate the surface. Also, being released at night it would not be subject to evapouration caused by sunlight.
I also imagine that these solar trees will function in all countries, not just Austria, or those in Western Europe.
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Region encoding can solve that problem.
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Well, here in northern Europe (southern Finland, to be exact), the days during the winter are short, the sun travels very low and the sky is usually very cloudy. Go to Lapland (in the northernmost area of Finland) and you won't be seeing the sun almost at all during the winter.
Solar power is great, but there are places where it just doesn't work.
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An interesting idea, but plants are already able to handle varying moisture conditions, while too-constant moisture promotes growth of damaging fungi. Rather than greener, you might end up with moldier.
Big parkingplex? (Score:2)
How big are their parking lots?
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s/Austia/Austria/g (Score:2, Informative)
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Looks promising (Score:3, Interesting)
As a citizen of Austria, I find it quite astonishing that this thing was able to provide light for a couple of days, although I have to admit that compared to now October still had plenty of daylight. I don't know whether or not they have been removed from the streets, but it would be pretty interesting to see for how long they can go in December/January, when it's quite dark throughout the entire month.
Apart from the energy savings, though, I wouldn't necessarily want to see them implemented throughout the city. Most of the 1st district's lighting is quite dim, giving the whole city with its many historic buildings a bit of a romantic flair, which - in my opinion - would be lost with all those bright lights everywhere.
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Funny... I live in Vienna, but havent't seen it... (Score:1)
Very inefficient compared to grid-tied panels (Score:4, Informative)
At night, the worst power plants are throttled back or shut down and the most efficient plants are handling the load.
When no further fossil fuels are used to make daytime power, then storing electricity from daylight becomes interesting and, even then, batteries are a loser.
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Earth Hour [wikipedia.org] was even more useless than this, but most people are stupid and need to be treated like little children with silly gimmicks to get them to pay attention: turn the god damn light off when you're not usin
Solar Tree? (Score:1)
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Well except the ones in chernobyl.. and those are killer zombie mutant trees anyway.
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Regular street lights produce way too much light, however. This causes people's eyes to adapt to brighter night-time light, which makes them blinder in places the street lights don't cover as well.
Furthermore, while the design looks attractive, it is not clear from the photograph that the light produced is fully shielded to prevent horizontal propagation and consequent energy waste and light pollution. If cities are looking to
Angle the panels... (Score:1)
Lighting Parking Lots??? (Score:2, Insightful)
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That depends. In many cases, break-ins are actually aided by ambient lighting, because people skulking around with flashlights are a lot more likely to be noticed, and unless you're skilled at ninjitsu, you're going to need some light. Motion-activated lighting is generally superior for crime prevention as it attracts attention. Yes, ambient lighting helps prevent people from tripping over things, but there's good evid
Taiyohh! (Score:1)
Can I get an angle, please? (Score:2)
Commercially available solar street lights (Score:2)
There are commercially available solar street lights [solarlighting.com] in the US. 5-day battery backup, resistant to 150MPH winds. "During the 2004 hurricane season in Florida, SLV models withstood ground zero wind conditions from category 5 hurricanes and typhoons." Just what's needed to provide light during emergencies.
The "Solar Tree" is more of an art project.
STOP THIS (Score:2)
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Looks promising, but snow? Pigeons? (Score:1)
These solar-powered city lights look practical only for cities where it doesn't snow. Those flat panels set parallel to the ground will collect piles of snow in the winter, possibly for weeks on end. After the batteries drain, the street below simply is not lit, which is a safety hazard. And for you suburban dwellers who assume street lighting's purpose is to show drivers where the curbs are: its primary purpose in cities is to cut down on street crime. Unlit city streets are a safety hazard not as a matter
won't someone think of the astronomers (Score:2)
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Not really. Artificial light affects limiting magnitude far from cities, and for many people, traveling to a place where the sky is really dark is practically impossible.
Take a look at these color-coded maps of artificial sky brightness [inquinamentoluminoso.it], or read up on the Bortle dark-sky scale [wikipedia.org].
falklands so bright? (Score:2)
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Good question. See the FAQ. [inquinamentoluminoso.it]:
Satellite data also record the offshore lights where oil and gas production is active (visible e.g. in the North Sea, Chinese Sea and Arabic Gulf), other natural gas flares (visible e.g. in Nigeria) and the fishing fleets (visible e.g. near the coast of Argentina, in Japan Sea and near Malacca). Note that their upward emission functions likely differ from the average emission function of the urban night-time lighting that we use so that the predictions of their effects have some uncertainty.
Theft (Score:1)
Laws (Score:1)
Less lights please (Score:2)
Hot stuff (Score:1)
>:(