Data Centre Futures: Energy - Reimagining the role of data centres in the energy system (Issue 02)

Overview

This document is the second issue of the Arup Foresight series (Issue 02, 2025), available as a free PDF. The issue covers growth in data centre electricity demand, grid connection queues, plateauing PUE and new supply options such as SMRs (small modular reactors). It contrasts annual-matching '100% renewable' claims with 24/7 location-based carbon accounting. The document aims to redefine the sector's place in the energy system not merely as a consumer but as a stakeholder in the grid.

Key figures give context: data centres use about 1.5% of global electricity (about 415 TWh). Some grid connection queues for new data centres are up to 10 years long. Hyperscale PUE improvements have plateaued; the chart of weighted-average PUE by IT capacity band uses Uptime Institute 2024 data. The figures show demand growing while efficiency gains slow and grid access becomes a constraint in its own right.

The 'early signs' section gives US examples: four SMRs providing 320 MW initially, rising to 960 MW, in Washington, and a 300 MW SMR project explored in Virginia. Arup's retrofit of the EMC2 Cork campus is expected to save 13 GWh and 7,000 tCO2 per year; another campus targets an annualised PUE of 1.2. An Arup expert piece proposes treating hyperscale campuses as anchor grid tenants that provide flexibility and waste heat. The recommendations are split into immediate efficiency and grid-responsiveness steps and longer-term structural reforms. Arup recommends location-based carbon audits and 24/7 clean-power commitments rather than certificate-matched renewable claims.

Key points

1. Data centres use about 1.5% of global electricity (~415 TWh).
2. Some grid connection queues for new data centres are up to 10 years long.
3. Hyperscale PUE improvements have plateaued; the chart uses Uptime Institute 2024 data.
4. US examples: four SMRs giving 320 MW rising to 960 MW (Washington); a 300 MW SMR project explored in Virginia.
5. Arup's EMC2 Cork retrofit expected to save 13 GWh and 7,000 tCO2 per year; another campus targets annualised PUE 1.2.
6. Recommends location-based carbon audits and 24/7 clean-power commitments over certificate-matched renewable claims.
7. Hyperscale campuses could be treated as anchor grid tenants providing flexibility and waste heat.

Using it in design

• Report both market-based and location-based carbon (hourly grid intensity) for a design.
• Let users model grid-connection date and on-site generation as site constraints.
• Display PUE against capacity-band benchmarks rather than a single industry average.
• Treat connection-queue duration as a schedule risk in the project plan.

Who should read it

Investors, consultants and design teams working on energy strategy, site selection and carbon reporting.

Related standards

• ISO/IEC 30134-2 (PUE)
• GHG Protocol Scope 2 Guidance

Publication details

Authors

Arup

Publisher

Arup (Arup Foresight)

Year

2025

Document number

Issue 02

Document language

English

Source type

Expert / community

Access

Free to read

Licence

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

Citation