[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