Swiss electrical equipment manufacturer ABB has bought a controlling stake in the US-based maker of data center electrical systems Validus for an undisclosed sum.

Validus specializes in direct-current (DC) power systems, which are considered to be more energy efficient than the traditional alternate-current (AC) systems but have not enjoyed widespread use in the data center industry because power supplies on most IT equipment take AC power.

A statement from the head of ABB’s Low Voltage Products division Tarak Mehta indicated optimism about the future of DC power technology in data centers. "DC systems provide data centers with a game-changing advantage in both operational and capital cost savings and we believe they will be widely adopted in this energy-intensive industry," he said.

Pushing DC power straight to the servers is more energy efficient because it requires fewer conversions to take place between the utility substation and the power supply.

In a traditional set-up, high-voltage AC power is fed into the UPS system, where it is converted to DC to charge the batteries. It is then converted back to AC before being fed to the servers’ power supplies. Every conversion step results in electrical losses, driving down energy efficiency of the system.

The ABB Group is a global conglomerate, specializing in power and automation technologies. The Zurich-based company employs about 124,000 people and has presence in about 100 countries.

Validus, based in Brookfield, Connecticut, has a comprehensive power-infrastructure portfolio for data centers, including conversion, distribution, battery-charging and energy-storage gear.