Originally Posted by ascii
How much more will it cost to maintain all those solar cells and biogas than just buy some mass produced energy from the local power company? One of these days all these little extra expenses are going to add up and Apple will find themselves unable to compete.
After initial purchase cost, maintenance on solar is near zero. Maintenance on a biogas generator is quite small. These things will reduce Apple's costs over the long term rather than increase it.
In my mind, this is a FAR better use of their cash than a dividend because the savings for the solar system will increase year over year. Most solar systems have a life of around 25 years. Want to guess what Apple's fuel or electricity costs would be in 25 years?
Solar involves a very high initial purchase cost and then near-zero operating costs. For a company which is cash-rich and doesn't have greater needs for the cash, it's a fantastic solution - even aside from the PR benefit.
I only wish that they had put the panels on the roof rather than clearing another 100 acres of forest.
Originally Posted by shadow415
FYI: The claim that the renewables "will provide 9.8 percent of the energy" comes from Greenpeace and is highly suspect. Their calculations assume that every device in the data center will be running at 100% its rated utilization for 100% of the time and there is zero overhead for redundancy.
It's sort of like calculating the annual power usage for your 1.1kW (1100W) toaster like this:
1.1kW * 24h * 365d = 9636 kWh per year
Which ignores the fact that even if you did you your toaster 24h a day, the element is not on that whole time. Thus, actual power consumed is much less.
Having been involved in the design and construction of large data centers, actual usage is nowhere near the maximum design rating of 200W psf.
Absolutely. Be very suspicious of what you hear from Greenpeace. With some experience in data centers, it is likely that the solar cells will provide a pretty large percentage of total energy usage. There's not enough public information to know for sure, but based on typical figures for a well designed system, it's large.
A good facility designed to reduce energy usage will use less than 30 kW per square foot (daily average). That would put the total energy usage at roughly 15 MW for this data center, with the peak usage occurring during daylight hours. Now, the solar system has a peak output of 20 MW, but taking into account nights, cloudy days, etc, they probably average only about 30% of that - or 6 MW. So the solar system can probably provide closer to 40% of the total power usage, not 9.8%. And if Apple is using state of the art methods to reduce energy usage, the power usage could be even lower, so solar might providing even more of the total.