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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.
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.