One of the most immediate and measurable advantages of Direct Current (DC) lighting lies in its lower installation costs. Traditional Alternating Current (AC) systems often require heavy-gauge copper conductors and steel conduit to safely carry high voltages throughout a building. By contrast, low-voltage DC lighting—typically operating between 24VDC and 48VDC—offers a fundamentally simpler and more efficient wiring approach.
Under the National Electrical Code (NEC), low-voltage LED lighting systems using Class 2 power supplies (limited to 100W output and 56VDC) are considered inherently safe. This classification eliminates the need for protected cable runs or metallic conduit, since the voltage levels are low enough to minimize shock or fire risk. The result? Installations that are faster, cleaner, and dramatically less material-intensive.
In a practical sense, this means that installers can run lightweight, plenum-rated cables directly above ceilings or through walls, without needing rigid steel conduit or heavy junction boxes. A typical Class 2 DC system uses 60% less copper—thanks to the smaller wire gauge—and 100% less steel, as conduit is no longer required. The reduction not only cuts material costs, but also labor time, since pulling conduit and threading wires through it are among the most time-consuming steps in a conventional AC lighting install.
A Real-World Example: Office Retrofit in Seattle
When a Seattle-based architecture firm retrofitted its 20,000-square-foot office with 48V DC LED lighting, it opted for a centralized Class 2 power distribution system. Instead of running 120V AC circuits and installing bulky conduits, the electrical contractor used plenum-rated low-voltage cable routed above the drop ceiling.
Material savings: The project reduced copper use by an estimated 58% compared to the original AC design.
Labor savings: Installation time for wiring was reduced by 35%, since no conduit bending or threading was required.
Aesthetic and flexibility gains: The simplified wiring made it easier to relocate fixtures during future reconfigurations, without the need for costly rewiring.Â
Broader Implications
For new construction, especially in environments like schools, data centers, or modern offices where sustainability and modularity matter, the benefits compound. Reducing the need for conduit means fewer penetrations in walls and ceilings, less coordination with other trades, and lighter structural loads.
In net-zero or all-electric buildings, DC lighting also aligns perfectly with on-site solar and battery systems, which natively generate and store energy in DC. This means fewer conversion losses—and even more savings on both energy and infrastructure.