Paul Singer is the chief technology officer of ABB Electrification. Here he looks at the future of power in smart buildings.
For more than 150 years, buildings have been designed around Alternating Current (AC) power. AC enabled the efficient electricity transmission over long distances from centralized power plants, shaping the electrical architecture of everything from commercial buildings to industrial facilities.
Today, however, the energy profile inside buildings is changing. Increasingly, both the supply and demand of electricity within buildings are native Direct Current (DC). Solar panels generate DC power, and battery storage systems charge and discharge in DC. In addition, many modern building loads—like LED lighting, electronics, EV chargers, and IT equipment—operate internally on DC.
As DC continues to grow, buildings are increasingly operating in a hybrid AC–DC environment. DC-powered technologies often convert incoming AC power to DC before they can operate. Each conversion step causes energy loss and additional equipment. By establishing a building energy architecture to deliver DC power more directly where it is needed while also supporting AC loads, facilities can eliminate conversions, improve efficiency, and enable integration of renewable energy generation and storage.
Improved efficiency creates significant savings
In large smart buildings, data centers, or industrial facilities with high energy use, even small inefficiencies can add up on the balance sheet. Consequently, the lower operating costs of newer, DC-based architectures can quickly offset their higher initial investment costs.
These facilities typically have multi-million-dollar electricity bills and intense scrutiny regarding their energy consumption. By eliminating unnecessary conversions, operators can achieve significant six-figure savings. ABB research has shown that DC-based architectures can reduce a building’s total energy costs by approximately 9%.
Improved efficiency provides another benefit, too: Fewer conversions mean less heat generated for the building’s HVAC and thermal management systems, so they don’t have to work as hard to keep systems from overheating.
Maximizing revenue through higher power density
The move to DC also addresses physical space constraints, which are one of the most pressing issues for modern developers. Every centimeter of electrical infrastructure is a centimeter taken away from revenue-generating assets. In an office building, for example, that could mean a lot of extra space freed up for additional tenants.
Traditional AC systems require bulky transformers and complex distribution boards. However, DC-native architectures, especially those that use Solid State Transformers, can eliminate up to two levels of conversion.
The result is an electrical footprint that is significantly smaller and lighter. We are seeing this play out in heavy manufacturing, where high-capacity industrial machinery is now being integrated into more compact, DC-native power systems. By shifting traditional AC transformers to high-power converters, more power density can be packed into the same physical envelope.
Overcoming the barriers to a DC future
Historically, the sticker shock of advanced power electronics and a lack of legacy industry standards were the primary barriers to DC adoption. Our entire electrical ecosystem has been built on a century of established safety and grid conformance standards for AC systems. Naturally, facility managers have been hesitant to connect complex DC systems without the guarantee of stability and safety.
However, technology is closing this gap. For example, advancements in power electronics significantly reduce the cost of DC power converters, while ultra-fast, solid-state circuit breakers provide the protection and control needed to safely manage DC power in high-energy buildings such as data centers. For modern smart buildings, this means facility managers can safely and directly power massive DC-native loads, like advanced HVAC systems, LED lighting networks, and on-site EV charging stations, while seamlessly integrating them with rooftop solar and battery storage. Because of these advancements, the ROI for high-energy facilities is essentially immediate, as DC architectures unlock efficiency and power density that traditional AC systems simply cannot support.
To further remove risk, the industry continues to use advanced digital twin simulations. Instead of relying on guesswork, facility designers and architects can virtually test how their on-site solar panels, battery storage, and high-capacity loads will interact in a hybrid ecosystem. Engineers can then demonstrate the stability, safety, and efficiency of a DC microgrid before a physical cable is laid, ensuring the system meets rigorous utility standards.
A leaner, high-performance infrastructure
By thoughtfully balancing both DC and AC infrastructure, facilities can drive greater overall system reliability and safety. This hybrid approach allows buildings to leverage the proven stability of the AC grid while strategically integrating DC systems to eliminate wasteful conversion processes wherever possible.
Whether you are operating EV charging infrastructure, a data center, or a modern office block, this balanced transition offers a path to a building that is leaner, more reliable, and significantly more efficient.