ABB and BCG Make the Case for DC Power in AI Data Centers

800-volt DC power distribution busbars feeding high-density AI data center racks

TL;DR · 30-second read

The Short Version

  • The Swiss engineering group ABB and the consultancy Boston Consulting Group published a report saying the electricity inside data centers should increasingly flow the way it does in a battery, not the way it does in a wall socket.
  • Computers, solar panels and batteries all run on that kind of power already. Every time electricity is converted from one form to the other, a little is lost as heat, like a phone charger warming up.
  • Artificial intelligence machines use so much power that those small losses now add up to real money and real capacity.
  • ABB sells the equipment, so it has a stake in the argument.

ABB said on September 9 that it has published The Strategic Case for Hybrid AC/DC Power: Shaping the Transition to the Next Electrical Architecture, a report developed with Boston Consulting Group. The Zurich-headquartered electrification and automation group argues that direct current, or DC, is moving from the periphery to the center of industrial, commercial and digital infrastructure, and that choices made by executives and policymakers over the next two to three years will decide who shapes the transition and who simply inherits it.

The report singles out AI data centers as one of the most immediate drivers of DC adoption, finding that 800-volt DC distribution is emerging as the defining architecture for next-generation AI infrastructure. It frames the outcome not as a contest between DC and alternating current, or AC, but as a hybrid system: AC remains the backbone of transmission and regional distribution, while DC spreads inside facilities where the major sources and loads already run natively on it.

Executive Summary

The argument rests on a piece of electrical plumbing that most people never see. Grids deliver alternating current, in which the flow reverses direction many times a second, because that form is cheap to push over long distances and easy to step up and down in voltage with transformers. Almost everything now growing fastest, though, is natively direct current: solar photovoltaic panels, batteries, electric vehicles, industrial automation gear and the graphics processors inside AI servers. Each handoff between the two forms runs through a converter, and each converter throws off a percentage of the energy as heat.

ABB and BCG contend that stripping conversion steps out of the chain does three things at once: it raises efficiency, it increases the usable compute capacity behind an existing grid connection, and it simplifies the integration of on-site generation and storage. That middle point is the commercially interesting one. In markets where new grid capacity is the scarce input, an efficiency gain converts directly into more revenue-generating hardware behind the same meter.

The report also reframes the obstacle. Concerns about DC at scale, its safety and its economics reflect outdated assumptions rather than the capabilities of current equipment, ABB and BCG conclude. What actually slows deployment, they say, is fragmented standards and a shortage of engineers and technicians trained on DC systems. That is a claim about institutions and labor markets rather than about physics, and it points to a slower, less predictable fix.

Why AI Racks Are Rewriting the Electrical Diagram

Conventional data center power design has been remarkably stable for two decades. Utility alternating current arrives at a substation, passes through switchgear, an uninterruptible power supply and a power distribution unit, then reaches a server whose internal supply finally converts it to the low-voltage direct current the chips actually consume. Each stage was tolerable when a rack drew a few kilowatts. The report’s contention is that at AI power densities, conventional architectures are reaching practical limits, and the accumulated conversion overhead stops being a rounding error.

The 800-volt DC figure is the specific technical claim worth understanding. Raising the distribution voltage lets a given amount of power travel through thinner conductors, because power is voltage multiplied by current and it is current that dictates copper cross-section and resistive heating. Delivering high-density racks at low voltage means either enormous busbars or unacceptable losses. Pushing distribution to 800 volts DC and converting close to the load is the same trick the automotive industry adopted for fast-charging electric vehicles, applied to a data hall.

The practical consequence is that the change does not stop at the rack. It touches switchgear, protection, uninterruptible power supply topology, on-site storage and the interface with the substation. That is a supply-chain shift as much as an engineering one, and it favors vendors who already hold the protection and conversion portfolios.

The Real Prize Is the Grid Connection

Read commercially, the strongest line in the release is not about efficiency in the abstract. It is that DC distribution lets operators maximize compute capacity within constrained grid connections. In the markets where AI capacity is being built hardest, the binding constraint is rarely capital or land. It is the megawatts a utility will actually deliver, and when they will deliver them.

Under that constraint, the economics change character. An efficiency improvement in a power-abundant market is a cost saving measured against the electricity bill. The same improvement behind a fixed, fully subscribed grid connection is a capacity unlock, measured against the revenue of the additional accelerators it lets you energize. Those two framings can differ by an order of magnitude in value, which explains why an argument about conversion losses is landing now rather than a decade ago.

It also explains the report’s two-to-three-year window. Electrical architecture is set early in a data center’s design and is expensive to revisit. Operators committing to buildings that will be energized late this decade are choosing their topology now, which is precisely when a vendor wants the conversation to happen.

Standards and Skills Are the Stated Bottleneck

ABB and BCG place the constraint on adoption in two unglamorous places: fragmented standards and a shortage of DC-specific skills. Both are credible. Direct current has no natural zero crossing, the instant of zero flow that lets a conventional breaker extinguish an arc, which is why DC protection historically demanded different hardware and different design practice. ABB says it launched the industry’s first solid state circuit breaker in 2022, and holds more than 700 DC-related patents.

That patent position is also why the call for harmonized standards deserves to be read with clear eyes. Common standards genuinely enlarge a market and reduce buyer risk, and buyers should want them. They also tend to reward whoever arrives with the deepest existing portfolio in the standardized technology. Nothing about that is improper, and ABB is not alone in it, but a customer evaluating this report should treat it as a well-argued position paper from an interested party rather than as neutral market research.

The skills point may be the more stubborn of the two. Standards can be negotiated on a schedule. A workforce of electricians, commissioning engineers and facility staff fluent in high-voltage DC protection is built over years, and its scarcity would constrain even operators fully convinced by the argument.

What Is Substantiated and What Is Asserted

The quantified evidence in the announcement is drawn from marine propulsion, where ABB says a DC-based onboard vessel power system achieved fuel savings of up to 27 percent. That is a real, specific result, and it is not a data center result. Ships run isolated power systems with variable-speed loads and their own economics; the number establishes that ABB has long-running DC field experience, not that a data hall should expect a comparable gain.

For the data center case itself, the announcement offers direction rather than magnitude. It says 800-volt DC is emerging as the defining architecture and that efficiency and usable capacity improve, without published percentages, capital-cost comparisons or named deployments in the summary. The conclusion that scale, safety and economic objections are now outdated is likewise stated as a finding, with the supporting analysis sitting in the full report published on ABB’s site.

None of that undercuts the thesis, which aligns with where high-density computing and on-site storage are visibly heading. It does mean the announcement is best treated as a framing document. The buyer’s question is not whether DC distribution helps, but by how much, at what installed cost premium, and with which protection and service ecosystem behind it.

Background

The choice between alternating and direct current was settled commercially in the late nineteenth century, when transformers made it cheap to step alternating voltage up for long-distance transmission and back down for use. Direct current never disappeared, though. It survived in specialist niches such as long submarine transmission links, traction systems and shipboard power, and it returned quietly through the back door as solar panels, batteries and electronics proliferated, each of them a direct current device tethered to an alternating current grid through a converter.

ABB sits on both sides of that history as one of the largest electrification and automation suppliers globally, selling switchgear, drives, protection and power distribution equipment into utilities, industry and data centers. The AI buildout has made its data center segment strategically prominent, because the constraint on new compute has shifted from chips and capital toward electrical delivery. This report, produced with Boston Consulting Group, is the company’s argument that the resulting architecture will look meaningfully different from the one the industry has built for the past twenty years.

Sources

Source: New ABB and BCG report highlights growing role of direct current technologies in future power systems — ABB’s September 9, 2026 announcement of a report developed with Boston Consulting Group on the shift toward hybrid AC/DC electrical architectures, including 800 VDC distribution for AI data centers. The full report is published at abb.com.