12V vs. 120V LED Garden Lights: The Physics of Low-Voltage Landscape Lighting

Low-voltage 12V systems are the standard for most LED Garden Light installations. The main reason is safety. At 12 volts, a nicked wire during a weekend digging project won't send you to the hospital. You can install these fixtures yourself without a licensed electrician. But there's a catch: voltage drop. Because the voltage is so low, resistance in the wire eats up the power fast. Run a 12V line 100 feet, and the light at the end might only receive 9 or 10 volts—enough to cause flickering or dimming. To fight this, you use thicker copper wire or split the run into shorter branches with multiple transformers.

Then there's 120V line voltage. It’s the same power that runs your washing machine. You can run it hundreds of feet without worrying about voltage drop, making it ideal for large properties. But it requires code-compliant burial depth, rigid conduit, and GFCI protection. One wrong move with a shovel, and you’re looking at a serious shock hazard.

The physics of scale also apply to commercial infrastructure. You won't find a 12V High Mast Light illuminating a port terminal. High mast systems run on high voltage because the sheer wattage and distance demand it. The physics that make 12V safe for a garden path make it useless for a 30-meter pole.

Interestingly, the rise of Solar Street Light technology is changing the game. These units bypass the grid entirely, using their own low-voltage DC systems powered by the sun. It’s the ultimate "low-voltage" setup—no trenching, no transformers, no shock risk.

Ultimately, 12V wins for safety and DIY installation. 120V wins for distance and heavy loads. Choose based on the length of your run and how much voltage you can afford to lose along the way.