Immersion Comparison
How does immersion cooling compare to air cooling and water cooling?
E3 NV has experience with air-cooled data centers, air-cooled modular data centers, several direct-chip-technologies, single-phase immersion, and most recently two-phase immersion. The info below is based on our real-world experience and the experiences of our customers.
Air Cooling
Pros:
Extremely well understood and quantified
No additional cost
Current OEM systems are designed for air cooling
Equipment is easy to service
No plumbing
Good scaling from small to large
Cons:
Extremely Noisy
Requires more frequent maintenance
Low density – higher cost for servers (per core)
Inefficient – Fans waste 25% of IT power on DL380’s
Large footprint
More networking equipment
Single-Phase Immersion
Pros:
Already well understood
Simple control systems
Up to 75% reduction in cooling power
Engineered fluids are less expensive than two-phase
Very high material compatibility
Lenovo offer OEM warranty for servers
Cons:
Equipment is covered in fluid when removed
Not as efficient as two-phase
Plumbing can get complex quickly
Does not scale well to multi-megawatt sizes
Requires larger, more expensive cooling coils
Two-Phase Immersion
Pros:
High build quality by necessity
Up to 98% reduction in cooling power
Long life fluid (20 years)
High cooling capacity (4kw per liter)
Equipment is dry and clean when removed
Fairly simple plumbing
Excellent scaling
Cons:
Not ideal at small scales
Control costs are the same for 250kW and 10kW
Controls are complex and expensive
Cannot use HDDs
Tanks must be stainless
Fluids leak easily so quality control must be tightly adhered to
Direct to Chip Water Cooling
Pros:
Well understood
Up to 60% reduction in cooling cost
Almost all servers can be modified
Easy road to higher density
Cons:
Still have fans
Large footprint for plumbing and chillers
Awful scaling – Infrastructure size grows faster with higher densities
Greatly increased maintenance costs
High additional cost