CyrusOne’s Liquid Cooling Strategy: How Billions in 2025 Investments are Powering the AI Data Center Boom

Industry Adoption: CyrusOne’s Pivot from Liquid-Cooling-Ready to AI-Dominance

Between 2021 and 2024, CyrusOne laid the strategic groundwork for the artificial intelligence (AI) era, methodically shifting from traditional cooling to a liquid-cooling-first mindset. This foundational period was defined by capability building and proving technological viability. The pivotal moment was the August 2023 launch of its Intelliscale™ platform, an AI-purpose-built data center design engineered to handle extreme power densities up to 300 kW per rack. This was not a theoretical exercise; it was a direct response to the thermal constraints of next-generation GPUs. During this time, the company championed water conservation, with 83% of its 2023 new builds using “water-free” closed-loop systems, and proved its efficiency gains by achieving a Power Usage Effectiveness (PUE) of 1.18 at a 54 MW Frankfurt campus developed with Airedale. The acquisition by KKR and GIP in 2022 provided the capital to make these initial investments, positioning liquid cooling as a commercially ready and sustainable solution.

The year 2025 marked a dramatic inflection point, shifting the strategy from readiness to aggressive, large-scale execution. The period began with CyrusOne securing a staggering $9.7 billion in debt capital, explicitly earmarked for AI-driven growth. This capital immediately fueled a series of ambitious projects that moved beyond standalone cooling systems. The June 2025 partnership with European energy giant E.ON to develop a 61 MW on-site power and cooling plant in Frankfurt is a landmark event, integrating power generation directly with baseload cooling via absorption chillers. This represents a new paradigm, solving the power and cooling nexus simultaneously to overcome grid constraints. Further, the announcement of massive new campuses, such as a proposed 600 MW site in Illinois featuring closed-loop cooling and a 100 MW AI-optimized center for the U.S. Navy, demonstrates a transition to deploying these advanced cooling technologies at an unprecedented scale. The variety of applications—from grid-independent integrated power plants in Europe to secure government AI facilities in the U.S.—signals that liquid cooling is no longer a niche option but a core, versatile component of critical digital infrastructure. This acceleration creates new opportunities in grid-edge solutions and specialized infrastructure but also introduces threats related to supply chain capacity and the execution risk of highly complex, multi-gigawatt projects.

Table: CyrusOne’s Strategic Investments in High-Density Cooling Infrastructure

Table: CyrusOne’s Key Partnerships for Next-Generation Data Center Cooling

Geographic Expansion: CyrusOne’s Global Footprint for Liquid Cooling

Between 2021 and 2024, CyrusOne’s geographic focus for advanced cooling was concentrated in Europe, particularly Germany. Projects like Frankfurt V (FRA5), FRA6, and the collaboration with Airedale on a 54 MW campus underscored a strategy to meet Europe’s stringent sustainability standards and high energy costs by deploying efficient, closed-loop liquid cooling. This period also saw a significant strategic entry into Asia through the joint venture with KEPCO to develop 900 MW in Japan, signaling intent to bring its high-density cooling expertise to another key technology market. The U.S. activity, while present, was more about preparing for future demand, such as the lease agreement in Northern Virginia.

From 2025 onwards, the geographic strategy dramatically expanded and intensified within the United States, solidifying it as the primary theater for hyperscale deployment. While European investment continues with the innovative E.ON partnership in Frankfurt, the scale of U.S. projects announced in 2025 is on another level. The planned 600 MW campus in Illinois and the 400 MW Thad Hill campus in Texas represent a massive domestic build-out. These regions are being targeted for their land availability and potential to support enormous power loads. Furthermore, the 100 MW project with the U.S. Navy in California demonstrates a new focus on specialized, secure deployments in critical domestic locations. This geographic shift indicates that while Europe was the proving ground for efficiency and sustainability, the U.S. is now the primary battleground for capturing the immense AI capacity demand. The risk shifts from navigating European regulations to overcoming power generation and transmission bottlenecks in key U.S. markets.

Technology Maturity: CyrusOne’s Journey from Pilot to Petascale Liquid Cooling

In the 2021-2024 period, CyrusOne’s liquid cooling technology was in a “commercial readiness” phase. The company was designing all new facilities to be “liquid-to-chip cooling ready” and promoting water-free cooling as a standard, commercially available offering. The launch of Intelliscale™ in 2023 was the culmination of this phase, productizing a modular solution capable of integrating various liquid cooling methods, from rear door heat exchangers to full immersion. However, these were largely platforms and capabilities waiting for mass-market demand. The partnerships with Airedale and KEPCO were about deploying and planning for these technologies, validating their efficiency (1.18 PUE) and scaling potential (900 MW plan), but large-scale customer deployments of 300 kW racks were still on the horizon.

By 2025, the technology matured from a “ready” solution to a cornerstone of major commercial projects. It is no longer just an offering but an enabling technology for multi-billion-dollar investments. The E.ON partnership in Frankfurt showcases this maturity by integrating cooling technology (absorption chillers) directly with a dedicated power plant, moving beyond the data hall and into utility-scale energy systems. This is a system-level solution, not just a rack-level one. Similarly, the Ameresco/U.S. Navy project specifies an “AI-optimized” data center, confirming that advanced cooling is now a prerequisite for high-value contracts. The technology has transitioned from being a feature on a spec sheet to a critical dependency for securing power, unlocking grid-constrained sites, and winning large-scale AI customer agreements. The focus has shifted from proving efficiency to enabling gigawatt-scale deployment.

Table: SWOT Analysis of CyrusOne’s Liquid Cooling Strategy (2021-2025)

2025 Forward Look: Decoding CyrusOne’s Next Moves in Liquid Cooling

The data from 2025 paints a clear picture of what lies ahead: CyrusOne is using its advanced cooling strategy as a lever to solve the single biggest obstacle to AI growth—power availability. The E.ON partnership is the most critical signal to watch; if this 61 MW integrated power and cooling model proves successful, expect CyrusOne to replicate it aggressively in other power-constrained markets across Europe and North America. This moves the company beyond a real estate and colocation provider into a quasi-utility infrastructure partner for its largest clients. The next signal to monitor will be the first major customer deployment on the Intelliscale™ platform, specifically which liquid cooling variant (e.g., direct-to-chip, immersion) is chosen and at what scale. This will set a de facto standard for hyperscale AI deployments. Finally, the progress of the massive 600 MW Illinois and 400 MW Texas campuses should be tracked closely. Their development will test CyrusOne’s ability to manage a complex supply chain and execute at a speed and scale few can match, solidifying its position as a dominant force in the AI infrastructure landscape. The strategy is no longer just about cooling chips; it’s about powering and enabling entire ecosystems.

Frequently Asked Questions

Why is CyrusOne investing so heavily in liquid cooling?
CyrusOne is investing heavily in liquid cooling because traditional air-cooling methods are insufficient for the extreme heat generated by next-generation AI hardware. The company’s Intelliscale™ platform is designed for power densities up to 300 kW per rack, a requirement driven by the thermal constraints of advanced GPUs. This investment allows them to support the high-density workloads of the AI boom efficiently and sustainably.

How is CyrusOne funding its massive 2025 expansion into AI data centers?
The expansion is primarily funded by a staggering $9.7 billion in debt capital secured in January 2025, which was explicitly earmarked for AI-driven growth. This was made possible by the company’s 2022 acquisition by private equity firms KKR and Global Infrastructure Partners, which provided the initial capital to position the company for such large-scale investments.

What makes CyrusOne’s partnership with E.ON in Frankfurt unique?
The E.ON partnership is unique because it moves beyond typical data center cooling and tackles the power problem simultaneously. They are jointly developing a 61 MW on-site combined power and cooling plant. This integrated system uses absorption chillers to provide baseload cooling, representing a new paradigm that overcomes local grid constraints and creates a more resilient, self-sufficient infrastructure for AI customers.

How has CyrusOne’s strategy evolved from 2021 to 2025?
Between 2021 and 2024, the strategy was focused on ‘readiness’—building capabilities, proving technological viability with platforms like Intelliscale™, and establishing a ‘liquid-cooling-first’ mindset. In 2025, the strategy shifted dramatically to ‘aggressive, large-scale execution,’ leveraging billions in new capital to deploy these advanced cooling technologies in massive new campuses and integrated power projects, moving from a proven concept to market dominance.

Is CyrusOne only focused on liquid cooling, or does it use other methods?
While CyrusOne has a ‘liquid-cooling-first’ mindset for high-density AI, it employs a variety of advanced cooling strategies tailored to specific needs. For example, the planned 600 MW campus in Illinois is designed with ‘closed-loop air cooling’ to ensure water efficiency at a massive scale. The company’s strategy is about using the most efficient technology for the job, which includes a range of solutions from free-air cooling and rainwater reuse to direct-to-chip liquid cooling.