How Modernizing Aging Data Center Infrastructure Improves Sustainability

Overview

Under greenhouse gases the paper counts SF6 from MV switchgear and HFC refrigerants. It describes three routes: digitalising and connecting existing equipment, swapping modular components, and replacing whole systems, each with a worked example (sensor-equipped switchgear, an MV switchgear breaker retrofit, a UPS replacement with an efficient mode), plus a cooling replacement case. Seven decision factors guide the choice: sustainability priorities, budget, maintainability, technology, location, performance gaps and disruption.

Lifetimes are concrete: LV switchgear 15 to 25 years and MV switchgear 30 to 40 years, with frames, barriers, busbars and transformers lasting up to 40 years while breakers, contactors, fuses and relays fail sooner. Retrofitting a typical 12-cubicle MV installation instead of replacing it avoids 37.2 tonnes CO2, 357 m3 of water and 10.6 tonnes of material (68% of line-up weight); un-recycled SF6 from obsolete breakers would equal 183.3 tCO2 (Figure 6 shows 185.3 tCO2eq). UPS life expectancy is generally 10-15 years, and a UPS running at 25% or lower is a candidate for replacement by a smaller unit.

On UPS efficiency, eConversion mode at 99% against double conversion at 97% cuts energy losses by a factor of 3 (Table 2); for a 1MW UPS against 95% double conversion this is 3.1 GWh saved over 10 years at 90% load and 1.6 kilotonnes CO2 at 0.453 kg/kWh. A diesel generator produces 714 kg CO2/MWh, so a 2-hour loss of primary power yields 1428 kg CO2 per MWh.

For cooling and water, a 1MW data centre in Sydney with a chiller/tower baseline and no economizer emits 7.3 kilotonnes CO2 per year versus 4.4 kilotonnes for air-cooled economizer approaches (40% lower, 29 kilotonnes over 10 years). A 1MW facility with water-cooled chillers and cooling towers uses about 25 million litres of water per year (Uptime Institute). A PUE of 2.0 means one watt of infrastructure power per watt of IT, and modern data centres can achieve PUEs below 1.5.

Key points

1. PUE 2.0 means one watt of infrastructure per watt of IT; modern data centres can reach below 1.5.
2. A diesel generator produces 714 kg CO2/MWh; a 2-hour loss of primary power yields 1428 kg CO2 per MWh.
3. LV switchgear lasts 15-25 years and MV 30-40; frames, barriers, busbars and transformers up to 40 years, breakers, contactors, fuses and relays less.
4. Retrofitting a 12-cubicle MV installation avoids 37.2 t CO2, 357 m3 water and 10.6 t material (68%); un-recycled SF6 would equal 183.3 tCO2 (Figure 6: 185.3).
5. UPS life is 10-15 years; a UPS at 25% load or lower is a candidate for a smaller unit.
6. eConversion (99%) versus double conversion (97%) cuts losses by a factor of 3; for a 1MW UPS, 3.1 GWh over 10 years and 1.6 kt CO2.
7. Sydney 1MW: chiller/tower with no economizer emits 7.3 kt CO2 per year versus 4.4 kt with air-cooled economizers (40% lower; 29 kt over 10 years).
8. A 1MW facility with water-cooled chillers and towers uses about 25 million litres of water per year.

Using it in design

• Add expected-life defaults to the asset catalogue (LV switchgear 15-25, MV switchgear 30-40, UPS 10-15 years), insulation medium for MV gear (SF6 or SF6-free), refrigerant with GWP for cooling units, and links to PEP/EPD documents.
• In brownfield mode flag UPS loaded at 25% or less as right-sizing candidates, SF6 switchgear for end-of-life planning (IEC 62271-4 handling) and high-GWP refrigerants (R134a, R410a).
• In the carbon calculator use 714 kg CO2/MWh for generator runtime and the site grid factor for Scope 2, and compare double conversion with eco/eConversion UPS modes in annual kWh and tCO2.
• In the water calculator compare about 25 million L/yr per MW for chiller and tower plants with dry or air-cooled economizers.

Who should read it

Designers planning brownfield modernisation and decision makers weighing sustainability and capital spend.

Related standards

• IEC 62271-4
• IEC 62040-3

Publication details

Authors

Wendy Torell; Sanaz Haji Hosseinzadeh

Publisher

Schneider Electric

Year

2022

Document number

WP 45

Document language

English

Source type

Manufacturer

Access

Free to read

Licence

Copyright retained; citation only — the publisher’s terms apply to the original document

Citation