Greenpeace released a report yesterday titled "How Clean is Your Cloud?" that looked into the energy sources powering the major IT players' cloud operations. The report praised Facebook, Yahoo and Google for their leadership in using renewable energy to power their data centers, but chastised Amazon, Microsoft, and especially Apple for still relying heavily on coal power. But Apple refutes the numbers Greenpeace used in their calculations, namely the power demand of their Maiden, NC data center, the facility that will soon be home to the largest end-user-owned solar array and the largest non-utility fuel cell installations in the country.
Apple released a statement in response to Greenpeace's report saying that the data center would use about 20 MW of power opposed to the 100 MW power demand Greenpeace used in their calculations. Greenpeace ranks Apple as getting 15.3 percent of their energy from renewable sources and 55.1 percent from coal, but obviously a difference of 80 MW would change those numbers significantly. But Greenpeace is sticking by their numbers, saying:
"When Apple announced they were building a data centre in North Carolina, they announced a commitment to invest $1 Billion (USD) over 10 years. For a number of the facilities in the “How Clean is Your Cloud?” report, we made estimates of power demand using fairly conservative industry benchmarks for data centre investments: 1MW of power demand from servers for every $15 million, though the number is often closer to $8 million for many companies. Thus, a $1 billion investment should net Apple 66MW of computer power demand. Assuming a fairly standard energy efficiency factor for new data centres for non-computer energy demand of 50% gives you a 100MW data center... The size of the facility at 500,000 sq foot would also indicate a much larger power demand. Amazon's chief web engineer recently conservatively estimated that based just on the size of the facility, the iDatacenter would consume at least 78MW, and speculated that it is probably higher."
Greenpeace also states that they provided Apple with their estimates before publishing the report and although Apple said they didn't agree with the numbers, they didn't provide the correct ones. But even if they were left to come up with an estimate on their own, the math seems way off.
Rich Miller at Data Center Knowledge brings up two major flaws: (1) Greenpeace isn't accurately factoring in the renewable energy that Apple is, and will soon be, using and (2) estimating the power load of a data center is near to impossible. The 15.3 percent that the organization says Apple gets from renewable energy assumes that the company's Prineville, Oregon data center, which is under construction, will use coal power, but that data center is actually planned to be fully powered by renewable energy. Also, Greenpeace assumes that the Maiden, NC data center will only get 10 percent of its energy from the on-site renewable energy installations, while Apple reports that those installations will cover at least 60 percent of energy demand.
Miller says Greenpeace made a major mistake basing their numbers on the $1 billion investment in the data center, assuming that all of that money was going into the data center itself and not accounting for the chunk that would be spent on the renewable energy projects and that square footage is also a bad indicator since different companies fill that square footage with differing amounts of computing vs. non-computing equipment -- there's no standard to use for that calculation.
While Greenpeace is right to put pressure on these companies to be more transparent about their energy use and where they're getting that energy from, the organization is stepping into sticky territory by coming up with their own numbers for that purpose. It ultimately calls into question the reliability of the report as a whole and undermines the cause of pushing these companies to move to cleaner sources of energy.