[easygenes]

That article cites a 100,000 sq. ft. data-center as the source for that $8 million savings estimate, along with roughly a 30% power savings figure. No mention on the period, so presumably it would be a TCO for the servers going into the initial buildout.

100,000 sq. ft. is roughly enough space for about 250,000 1U servers. Say conservatively the servers are in the ballpark of $2,000 each. That's $500 million just in server hardware costs. If the total electric cost is around 3*$8 = ~$24 million over their lifetime, then we're talking about <5% of just the server expenses. Never mind the facility and staff costs (and, as you've said, connectivity).

So maybe not a rounding error, but way down the priorities list.

[klelatti]

These are AC costs not total costs and the $8m is probably an annual figure - although it's not clear.

[easygenes]

Yeah, unfortunately it's a bit vague on the period. It is not unreasonable to assume an annual figure, in which case you're looking at something closer to 20% of the server costs for A/C power (assuming an average life of about 4 years).

Problem is, that sounds high... the coefficient of performance for chillers is around 4 to 7 [1]. That puts ~15-30% of the total energy demand from chillers, though often datacenters do budget a factor up to about 60% of equipment power demand for cooling power demand. Sum energy related expenses for datacenters tends to be around 10-15% of the total costs [2]. So it would be odd to have such high cooling costs. A TCO over 4 years seems more in line with typical figures.

  1: https://www.energy.gov.au/sites/default/files/hvac-factsheet-chiller-efficiency.pdf
  2: https://www.missioncriticalmagazine.com/ext/resources/MC/Home/Files/PDFs/(TUI3011B)SimpleModelDetermingTrueTCO.pdf