Sustainability
Energy, water and diesel
A data center turns electricity into heat on purpose. Our job is to waste as little as possible doing it, to burn as little diesel as we can while still being ready to burn a great deal, and to publish the numbers either way.
01 Efficiency
Power usage effectiveness
PUE is the energy a building uses divided by the energy its IT equipment uses. A PUE of 1.43 means that for every kilowatt-hour a customer’s servers draw, the building spends 0.43 more on cooling, power conversion and lights. Ours are annual figures, measured at the UPS output, which is the honest place to measure them and not the flattering one.
| Year | SEC1 | NWK1 |
|---|---|---|
| 2019 | 1.58 | — |
| 2020 | 1.55 | 1.44¹ |
| 2021 | 1.52 | 1.38 |
| 2022 | 1.50 | 1.36 |
| 2023 | 1.47 | 1.34 |
| 2024 | 1.45 | 1.32 |
| 2025 | 1.43 | 1.31 |
¹ June to December 2020, with Level 1 lightly loaded. SEC1 is an old building with water-cooled chillers and cooling towers; NWK1 is newer, air-cooled and gets more hours of free cooling. SEC1’s water usage effectiveness in 2025 was 1.21 liters per kilowatt-hour; NWK1 uses water only for humidification.
02 Diesel
Diesel
| 2025 | SEC1 | NWK1 |
|---|---|---|
| Generator run time, all sets | 212 set-hours | 196 set-hours |
| of which tests | 118 | 168 |
| of which utility events | 94 | 28 |
| Fuel burned | 21,400 gal | 14,900 gal |
SEC1’s utility events in 2025 were almost all on one afternoon, June 24. Since March 2026 every generator at both sites runs on hydrotreated renewable diesel, made from waste fats and oils. Our supplier’s certificates put its life-cycle carbon emissions about 70% below conventional diesel. It does not change what comes out of the exhaust stack much, which is why every set at SEC1 also now has catalytic reduction and a particulate filter; see the page for neighbors.
03 Electricity
Where the electricity comes from
Both sites buy electricity from the regional grid. In 2025 we matched 61% of our annual consumption with renewable energy certificates from wind and solar projects connected to the same grid, and 34% hour by hour. We would like the second number to be the one people quote. It is the harder one to improve.
04 Using less
The cheapest kilowatt-hour
We sell space and power, and we would still rather you used less of both. Storage that nobody reads is the easiest saving in most of our customers’ cabinets. An essay from Frothly’s archive program on the slow entropy of unused data (FR-E-2026-09, April 2026) found that in the stores of forty organizations it reviewed, 68% of files were never opened again after the day they were created. Our remote hands will happily decommission a shelf of disks for you, and the drives go to a certified shredder with a certificate for each serial number.
Frothly’s research is listed at frothly.org/research.