Invisible schrieb:

>> Of course they are waterproof, they are also lots-of-snow and 
>> big-lumps-of-ice proof.  Otherwise people wouldn't put them on their 
>> roof. FWIW there are different ratings depending on how much snow-load 
>> you want to support.
> 
> Wait - I thought that was still science fiction? You mean people 
> somewhere *actually do this* now??

Definitely so. Seen this a /lot/ in south-eastern Germany, too. And the 
house I grew up in (and which my parents sold some months ago) has just 
been equipped with solar panels, too (not sure whether the photovoltaic 
or water-heating type) - even despite it being on a hillside facing 
north, in a particularly rainy valley of a particularly rainy area of 
western Germany.

It's really gearing up these days in Germany. I guess the development of 
oil prices in the last 1-2 years are taking effect: People started 
getting aware in a very practical way that we'll not be able to live on 
fossil fuels forever.

It's still not competitive with grid power /yet/, but the government 
does a lot here to support such investments, so for the end user it does 
pay off. All the more if you figure in future oil price rises, which 
people in Germany have started to do. It's now actually considered a 
financial investment over here, not just an ecological one.

And I just read that for instance in Hawaii, solar power is now already 
cheaper than ordinary grid power.

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Invisible schrieb:
> One thing a lot of people don't seem to realise is that the brain does 
> *other stuff* besides thinking...

Sure - but given that evolution added(!) some 200% more brain mass to 
Homo Sapiens over his ancestors and relatives, apparently /for/ thinking 
(and speaking, which appears to be a closely related task), I guess it 
is reasonable to assume that the /majority/ of our brain's capacity is 
devoted on it.

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Invisible schrieb:

> Hmm. What's the TDP of a typical CPU? About 150W? Oh dear...

For a laptop CPU, you're going for a good deal less.

Also note that's the /maximum/ rating.

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clipka wrote:
> And I just read that for instance in Hawaii, solar power is now already 
> cheaper than ordinary grid power.

The big kicker is installation/material cost.  Last I checked, at normal 
usage, with both electric and water heating done or supplemented by 
solar, it'd take like 20 years to recoup the price...but it *would* be 
regained.

--
Tim Cook
http://empyrean.freesitespace.net

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On 21-9-2009 15:16, clipka wrote:
> Invisible schrieb:
> 
>> (I love the way turning my PC on requires 50% more power than playing 
>> a 3D-intensive computer game...)
> 
> Yeah, the turn-on is always the hardest part :-P

All those electron that have to get up to speed. When they are moving it 
costs less to keep them at speed. Or maybe not.

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On 21-9-2009 15:10, Verm wrote:
> clipka wrote:
>> Invisible schrieb:
> 
>> With a laptop about as large as an A4 sheet of paper - about 100 
>> square inch - that would give you... 7 Watts. Not /quite/ the order of 
>> magnitude you'd probably need...
> 
> That's nearly enough to power a low-power laptop.
> The OLPC (one laptop per child) scheme says their laptops are limited to 
> use 15 Watts
> http://laptop.org/en/laptop/hardware/specs.shtml

That is what they are limited to. IIRC the goal was about 2W as you can 
generate that as a human being of child like proportions. Might be in 
this video 
http://www.ted.com/talks/nicholas_negroponte_on_one_laptop_per_child_two_years_on.html



> So 7 watts is nearly there - you could fit a fold-out panel on the back 
> of the laptop or do something cunning with mirrors / fresnel lenses to 
> focus more sun on the panel.
> 
> I believe my mini ITX server uses 10 - 20 W depending on load and it's a 
> 1 Ghz machine with a fullsize hard drive but no display and it's not the 
> most efficient design out there.
> 
> On the other hand "my" blade centre with 12 quad core servers in it uses 
> 1700 W which is more than 3x my house's average consumption.

There is that story about, I think, Shell that they build a new building 
with a giant heater for the winter, just when everything was nearly 
finished they brought in a supercomputer that needed a giant cooling 
system. A bit more communication would have saved a lot of money.

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Invisible wrote:
> If you built a laptop where the entire lid was a solar panel, would it 
> generate anywhere near enough power to run the laptop?
> 
> Would it even generate enough power to recharge the battery in a 
> reasonable amount of time?
> 
> (For reasons unknown, Dell sent me a free gift today: A solar charger. 
> Who knows, it may even be useful...)

Nope. I looked into it, even the EeePC line takes enough power to 
operate that you would need one of those folding panel things they now 
make, which unfolds to about 6'x4', if I remember right. Or, more 
specifically, you could probably manage it with like 5'x3', or 
something, but they don't make ones that size. One the size of the back 
of a laptop would only net you probably 30-40% (guessing) of the power 
needed, and that is without peripherals of any kind.

Recharging is a little less of an issue, but its going to take time to 
do it, and probably longer than a wall plug.

-- 
void main () {

     if version = "Vista" {
       call slow_by_half();
       call DRM_everything();
     }
     call functional_code();
   }
   else
     call crash_windows();
}

<A HREF='http://www.daz3d.com/index.php?refid=16130551'>Get 3D Models, 
3D Content, and 3D Software at DAZ3D!</A>

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andrel wrote:
> There is that story about, I think, Shell that they build a new building 
> with a giant heater for the winter, just when everything was nearly 
> finished they brought in a supercomputer that needed a giant cooling 
> system. A bit more communication would have saved a lot of money.

On the other hand at my site they did think about that, so they 
integrated the cooling of the machine rooms with the heating of the rest 
of the site....
10 years (or so) later our machines are a lot more efficient and create 
less heat so they no longer provide enough to warm the site, so a new 
gass powered heating system was needed.

I believe the "new" UK ATC centre on the south coast has the same 
problem - but they've not yet installed any more heating. (they switched 
from huge CRT displays to beautiful flatscreens that don't get as toasty)

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> I believe the "new" UK ATC centre on the south coast has the same 
> problem - but they've not yet installed any more heating. (they switched 
> from huge CRT displays to beautiful flatscreens that don't get as toasty)

Same happened at University - building had been planned to be full or CRT 
heaters, only everything got replaced by LCDs so we all froze.  At least 
that's what they claimed...

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Invisible wrote:
> 
> In fact, my old laptop idles at 20W, which is *still* too much. At best,
> the solar panel would double the battery life. (If it weren't for the
> minor detail that the battery is cluser-****ed anyway...)
> 

My old laptop runs ~35W on full power, according to ACPI. You just
happen to have a cheap-series powerhog ;).

-Aero

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