The Quiet Copper Revolution: How HVDC Is Rewiring the Data Center

The modern data center is a monument to copper. From power distribution to networking, megawatts of electricity move across kitchens-worth of busways, cables, and switchgear made overwhelmingly from one expensive, heavy, and increasingly volatile commodity. Copper has long been the backbone of digital infrastructure, but the industry is approaching a turning point.

A growing number of hyperscalers and colocation providers are experimenting with, piloting, or fully deploying high-voltage direct current (HVDC) power distribution as an alternative to the century-old AC architecture inherited from the grid. Their motivation isn't just efficiency gains or sustainability optics. One of the most compelling and least discussed drivers is copper. Specifically, the opportunity to use much less of it.

Copper prices have been climbing for years, driven by global electrification, EV demand, supply constraints, and geopolitical risk. Data centers are uniquely exposed: a single 50-MW facility can require millions of dollars in copper just for power distribution and bus systems.

Higher amperage at low voltage (480/415V AC and below) forces designers to use thick conductors to keep heat, impedance, and losses in check. AC also demands separate phases, harmonics filtering, and redundant conductors throughout the architecture. All of that adds more copper.

The problem scales linearly and painfully. Every additional megawatt requires more cable trays, more windings in transformers, more copper in breakers and switchgear, and more conductors feeding server rows.

By distributing power at 800V to 1,500V DC inside a data center currents drop dramatically.

Lower current means thinner conductors can move the same amount of power with less heat and lower losses. And because DC doesn’t require phases, neutral conductors, or many of the AC-side conditioning components, entire layers of copper-heavy equipment simply disappear from the electrical one-line.

Data center engineers are already seeing:

• 30–50% reduction in copper cabling mass

• 40–70% reduction in busway copper content

• Elimination of AC transformers and multiple stages of power conversion

• Lower mechanical load from cable trays, improving structural design flexibility

Some hyperscale pilots have reported even steeper reductions, particularly when combined with battery-in-rack systems that remove centralized UPS blocks, another copper-intensive subsystem.

One additional copper driver in AC systems, almost never discussed outside of engineering circles, is the skin effect. At 60 Hz, alternating current does not flow uniformly throughout the cross-section of a conductor. Instead, the current is forced toward the outer surface (“skin”) of the conductor. In copper at 60 Hz, the skin depth is approximately:

δ ≈ 8.5 mm (≈ 0.335")

This means that most of the effective conduction is limited to the outer ~1/3" of thickness. Any copper inside that depth contributes little to current-carrying capability but still adds weight and cost. Because thick solid bars waste interior copper, AC busways and switchgear must rely on wide, thin conductors, or multiple laminated bars stacked to build ampacity.

Both approaches drastically increase the amount of copper needed for a given current rating. The geometry is driven by physics, not preference: to maintain low impedance and acceptable thermal behavior under AC, you must expose more conductor surface area.

As currents rise, for example, in 415V or 480V AC feeder systems, the only way to stay within thermal limits is to add more laminated bars. This is why large AC bus ducts and switchboards often contain inches-thick stacks of copper.

HVDC completely eliminates the skin-effect. Direct current has no frequency, therefore no skin effect. The entire conductor cross-section is fully utilized, meaning:

• A smaller volume of copper carries the same current

• Fewer laminations are required

• Bars can be thicker without penalty

• Overall system impedance falls

• Heat generation is reduced

Combined with the higher voltage of HVDC (800–1500 V), which reduces current even further, this results in an almost linear reduction in copper mass. It is one of the quiet but powerful engineering advantages of the HVDC architecture.

When a facility switches to HVDC, the design shifts in several ways that each reduce copper:

1. Fewer Conversions

Traditional AC architectures step power down multiple times (medium-voltage → low-voltage → UPS → PDU → server PSU), with copper-rich equipment at each stage.

HVDC collapses this chain, often delivering DC straight from MV rectifiers to rack-level distribution.

2. No Neutral Conductor

AC needs three phases and a neutral. DC doesn’t. Eliminating the neutral conductor alone can cut total conductor mass by 25%.

3. No Harmonics Infrastructure

Harmonic filters, compensators, and certain transformers, all copper-heavy, aren’t needed in the same way in a DC system.

4. Shorter Cable Runs

Because HVDC can be distributed with smaller conductors, designers can route power more directly, reducing the total length of cabling needed.

Copper savings are real, but the transition isn’t trivial. The hurdles include:

• New switchgear ecosystems – Traditional AC breakers and protection systems don’t behave the same way with DC arcs

• Standardization gaps – Efforts like ETSI EN 300 132-3 (−48V DC) are mature, but high-voltage DC standards are still emerging

• Vendor lock-in – Fewer suppliers exist for HVDC rectifiers and distribution modules, though this is improving rapidly

• Workforce expertise – Electricians, facility managers, and commissioning teams need training to work safely with high-voltage DC

Still, the economic incentives are growing harder to ignore. When copper prices spike, HVDC ROI accelerates.

In addition, HVDC reduces power conversion steps, and therefore losses, typically improving power distribution efficiency by 2–8%. At hyperscale, this is worth millions of kilowatt-hours annually. And because cooling loads often follow electrical losses, the efficiency gains ripple into HVAC systems as well.

When Facebook announced its 48V DC server architecture years ago, many analysts saw it as a niche experiment. Today, with hyperscalers battling power scarcity, supply chain challenges, and material inflation, HVDC is edging toward mainstream acceptance.

Copper may be the hidden catalyst: the material that built the digital world may also be the reason data centers finally outgrow AC.

The next generation of facilities, AI supercomputing campuses, edge-scale microdata clusters, and greenfield hyperscale sites, are increasingly being specified with HVDC in mind. Not because it’s futuristic, but because it’s economically unavoidable.

The future data center will still be built on copper. Just far less of it.

Contact us to learn how Ennovria can help you reduce copper usage and future-proof your data center.