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Can the Sun Realistically Power Datacenters?
1sockchuck writes: A massive solar array in central New Jersey provides the daytime power for a server farm delivering online financial services for McGraw Hill. The 50-acre field of photovoltaic solar panels symbolizes a new phase in the use of renewable energy in data centers. Massive arrays can now provide tens of megawatts of solar power for companies (including Apple) that can afford the land and the expense. But some data center thought leaders argue that these huge fields are more about marketing than genuinely finding the best approach to a greener cloud.
Efficiency can be easy - we just need to build a Dyson sphere.
> The fact that some arrays were done in a way that's incompatible with farming doesn't mean that it can't be done.
The light either hits the corn leaves, or it hits the solar panel. The same photon won't hit both. You don't get to use that same bit of sunlight repeatedly. Each photon is either absorbed by the solar panel, or it's absorbed by the crop. You _could_ mix 25 acres of solar with 25 acres of farming, to have 50 acres of both mixed together. The productivity of mixing them together would be precisely the same as having 25 acres of farmland on one side of the street, and 25 acres of solar on the other side of the street. Mixing them, with ten feet of farm, ten feet of solar, ten feet of farm, ten feet of solar would be silly, though, because it's awfully hard to harvest the corn with solar panels in the way.
No, you have proven you didn't understand solar insolation vs daylight hours, even though I clearly gave you a link that explained it at high school level.
And, you fail to also read well documented fact that German solar capacity factor is less than 10% overall, equivalent of about 2.4 full sun hours.
http://euanmearns.com/german-p...
Your ignorance is intentional.
Read the post again - it's insOlation, which is correct, not insUlation, which was your assumption.
Solar PV capacity planning, at least in domestic situations, is based on the amount of energy captured/generated by a panel at its PEAK capacity, and is generally calculated at 5 hours/day in temperate zones, less in frigid, more in tropical, with modifiers for local conditions and climate. Panel output throughout, for example, a clear sunny day in the mid latitudes corresponds closely to a steep-ish bell curve (more like a sine wave, though). Low output at either end of the day because the incidence of the sun's rays to the panel are more oblique.
Panels are getting better at "catching" oblique insolation, but obviously they're much better between the hours of 9-10am and 2-3pm. There is a significant amount of energy captured outside these times, but it's not really useful when calculating the number of panels needed. It's better to state that you'll capture a minimum of x on sunny days, rather than a maximum.
They sentenced me to twenty years of boredom
Sigh.
The best solar PV plants in Germany have a capacity factor of about 13%.
http://en.wikipedia.org/wiki/S...
These are the plants in the best locations. That comes to an average solar insolation of 3.12 full sun hours/day. If you had 5 hours you should have closer to 20% capacity factor. I'll let you think about why they don't see 20%, and why the average capacity factor overall is 9.5%, and try to reconcile it yourself. When you get stumped, I'll gladly explain.
primordial, a.: existing at (or from) the very beginning; first in time, earliest. Ergo, hydrogen, helium, and lithium. Everything else came later.
Ezekiel 23:20