Introduction
Street lighting is a fundamental part of urban infrastructure, enhancing safety, supporting nighttime activities, and contributing to a city’s overall appearance. But with thousands—or even tens of thousands—of street lights in a metropolitan area, understanding their power consumption is critical for managing energy costs and environmental impact.

This guide explains how much power street lights use, the factors that influence their consumption, and the differences between various types of lighting technologies.

Average Power Consumption of Street Lights
The amount of power a street light uses depends heavily on its wattage rating and lamp type.

Typical Wattage by Lighting Technology
High-Pressure Sodium (HPS): 50W–400W, with common street applications between 100W–250W.

Metal Halide: 70W–400W, with higher brightness and color rendering.

LED Street Lights: 20W–300W, with common ranges between 30W–150W for most roads.

For example:

A traditional 150W HPS light uses 150 watts continuously when on.

A modern 60W LED street light delivers similar or better illumination with less than half the power.

Calculating Power Usage
Power usage can be expressed in kilowatt-hours (kWh), the standard unit for electricity billing.

Formula:

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Daily Energy Use (kWh) = (Wattage ÷ 1000) × Hours On Per Day
Monthly Energy Use (kWh) = Daily Energy Use × Days Per Month
Annual Energy Use (kWh) = Daily Energy Use × 365
Example:
A 100W LED street light running for 12 hours per night:

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Daily: (100W ÷ 1000) × 12h = 1.2 kWh
Monthly: 1.2 × 30 ≈ 36 kWh
Annual: 1.2 × 365 ≈ 438 kWh
If electricity costs $0.12 per kWh, the annual energy cost is:

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438 × $0.12 ≈ $52.56
Multiply this by hundreds or thousands of lights, and you see why power efficiency matters.

Factors Affecting Street Light Power Consumption
1. Lamp Type
LEDs consume far less power than traditional sodium or halide lamps for the same light output.

2. Wattage Selection
Higher wattage equals higher brightness, but also higher energy draw. Over-lighting can waste electricity.

3. Operating Hours
Typical street lights operate from dusk to dawn—about 10–14 hours depending on the season and location.

4. Dimming and Control Systems
Smart controls, timers, and motion sensors can reduce consumption by dimming lights during low-traffic hours.

5. Voltage Power Quality
Voltage fluctuations or inefficient drivers/ballasts can affect actual consumption.

LED vs. Traditional Street Light Power Usage
Feature LED Street Light (60W) HPS Street Light (150W) Metal Halide (150W)
Luminous Efficacy 120–160 lm/W 80–100 lm/W 70–90 lm/W
Energy Use per Hour 0.06 kWh 0.15 kWh 0.15 kWh
Annual kWh (12h/day) ~263 ~657 ~657
Annual Energy Cost* ~$31.56 ~$78.84 ~$78.84
Lifespan 50,000+ hrs 15,000–24,000 hrs 10,000–20,000 hrs

*Based on $0.12/kWh electricity cost.

Common Wattage Categories and Use Cases
20W–40W: Footpaths, alleys, residential driveways.

50W–90W: Local streets, small parking areas.

100W–150W: Main roads, busy intersections.

200W–300W: Highways, large industrial yards.

Choosing the right wattage helps balance visibility needs with energy savings.

How Cities Reduce Street Light Power Use
Switching to LED: The most impactful change, often cutting energy usage in half.

Adaptive Lighting Systems: Dimming lights when traffic is low or during late-night hours.

Solar-Powered Street Lights: Removing dependency on grid power entirely.

Smart Monitoring: Detecting outages and adjusting light levels remotely to optimize performance.

Environmental Impact
Reducing the power consumption of street lights lowers greenhouse gas emissions, especially in areas where electricity is generated from fossil fuels. A city-wide switch from HPS to LED can save millions of kWh annually, reducing CO₂ output by thousands of metric tons.

Quick Reference: Power Usage Examples
Light Type Wattage Hours/Day kWh/Day kWh/Year
LED (Low Power) 30W 12 0.36 131.4
LED (Medium) 60W 12 0.72 262.8
LED (High Output) 150W 12 1.8 657
HPS (Medium) 150W 12 1.8 657
HPS (High Output) 250W 12 3.0 1095

Conclusion
The power consumption of a street light depends on its wattage, technology, and operating schedule. Traditional lights like HPS and metal halide consume significantly more energy than modern LEDs. For municipalities and property managers, understanding and optimizing this usage can lead to substantial cost savings and environmental benefits. Upgrading to efficient technology, choosing appropriate wattages, and integrating smart controls are the most effective strategies for reducing power consumption while maintaining safety and performance. Get to know more at this article how much power does a street light use?