Datacenters and Solar Panels
By dd on Dec 18, 2009
This week i/o Data Center announced plans to cover their 11-acre Phoenix data center with solar panels. While I applaud their investment in clean energy, the details of the installation point to the current challenges that both data centers and solar energy face.
Our green energy guru, Mark Monroe, pointed out the following energy disconnect:
- When fully loaded, the 11-acre datacenter will use 120MW of power, or 1.05M MWh per year. If powered with coal-produced electricity, you're talking about a mile-long train of coal each week.
- When complete, the solar panels will generate 4.5MW peak. Using NREL's PVwatts site, we find that the annual output is projected to be 7.8K MWh per year.
- Result: the solar panels will cover 0.78% of the data center's power needs. So, basically, the coal train will be 40 feet shorter.
We're run some numbers some numbers on other data center projects, including making solar-powered Blackboxes and they all come out with similar results.
So is there a point to this, other than to be depressing? Believe it or not, there's some good things happening here.
First, large data centers have higher energy density than just about any kind of building. Homes, warehouses and office buildings are much lower, and even today's solar panels are aren't such a mismatch. So the extremeness of this case is a result of the contents of the building, not a statement about solar and buildings in general.
Second, the trend towards these mega, high density data centers is a good one. These new designs are generally much more efficient in power distribution and cooling, and larger projects have more budget to focus on efficiency. For example, look at the interesting things that they are doing to shift power demands between day and night. In other words, spreading the same computers over lots of small data centers would be less efficient. Do we have work to do on both the computers and the power and cooling? Yes, we have a long way to go. But don't let the consolidation upset you - its almost always the right thing. (And before someone sends me an email challenging the mental capacity of someone who'd put a datacenter in Phoenix, take a look at this chart from the Green Grid).
Finally, its great to see that they believe that a project of this scale will make economic sense over its lifetime. That's promising for other projects in two ways: 1) they are also likely to make sense, and 2) projects of this scale will help drive down costs of solar, and will make future projects even more financially sensible.