LED Solar Street Light Design Guide (2025 Edition)

1. Solar Street Light System Design Composition and Selection Standards

1. Core Component Configuration

Component	Functional Requirements	Selection Parameters
LED Light Source	Color temperature 4000-5000K, Color rendering index ≥70	Luminous efficacy ≥150 lm/W, IP65 protection
Photovoltaic Panel	Monocrystalline silicon efficiency ≥22%	Power = Daily system consumption / (Local average peak sunshine hours × 0.7)
Battery	Cyclic life ≥1500 times	Capacity (Ah) = Daily consumption (Wh) / (System voltage × Depth of discharge × 0.9)
Controller	MPPT efficiency ≥95%	Overcharge/overdischarge protection, load time-based control

2.Solar Street Light Key Design Parameter Calculations

1. Solar Street Lighting Demand Design

Formula:

P_LED = E × A / (η × U × K)

Parameter Explanation
E: Design illuminance (Main roads 15-30 lx, Branch roads 10-20 lx)
A: Illuminated area = Road width × Distance between lights
η: Luminaire efficiency (0.8-0.9)
U: Utilization factor (0.4-0.6)
K: Maintenance factor (0.7-0.8)

Example: Road width 6m, distance between lights 25m, target illuminance 20 lx

→ P_LED = 20 × (6 × 25) / (0.85 × 0.5 × 0.75) = 20 × 150 / 0.32 ≈ 94W

→ Choose a 100W LED module (Luminous flux 15,000 lm)

2. Solar Street Light Photovoltaic System Capacity Calculation

Steps:

Daily Consumption: Q_day = P_LED × Working Time (e.g.: 100W × 10h = 1000Wh)
PV Panel Power: P_PV = Q_day / (H_peak × 0.7)
- H_peak: Local average peak sunshine hours (e.g.: Beijing 4.5h)
- → P_PV = 1000 / (4.5 × 0.7) = 317W → Choose 2 × 160W modules
Battery Capacity: C = Q_day / (V_sys × DOD × 0.9)
- V_sys: System voltage (usually 12/24V)
- DOD: Depth of discharge (80% for lithium batteries)
- → C = 1000 / (24 × 0.8 × 0.9) = 57.6Ah → Choose 60Ah lithium battery

3. Solar Street Light Structural Design Specifications

1. Pole and Component Layout

Road Type	Pole Height (H)	Pv Panel Angle	Installation Distance
Branch Road	4-6m	Latitude + 5°	25-30m
Main Road	6-8m	Latitude + 10°	30-35m
Expressway	8-12m	Adjustable bracket	35-40m

Wind Resistance Design: Flange size ≥ pole diameter × 1.2 (e.g.: Pole diameter 76mm → Flange 200×200×10mm)

4. Solar Street Light Intelligent Control Strategy

1. Multi-Mode Operating Scheme

Time Period	Control Logic	Power Adjustment
18:00-22:00	Full power operation	100%
22:00-24:00	Dynamic dimming (traffic detection)	50-70%
00:00-6:00	Maintain minimum safety illuminance	30%

Backup Power: In areas with continuous rainy days ≥3days, configure a grid power complementary interface.

5. Installation and Maintenance Points

1. Construction Process

Environmental Assessment: Avoid tree/building shadows, obstruction < 2 hours on winter solstice.
Foundation Casting: Depth = Pole Height / 10 + 0.2m (e.g.: 6m pole → 0.8m deep).
Wiring Standards: Photovoltaic cable voltage drop ≤3%, Battery burial depth ≥0.5m.

2. Operation and Maintenance Cycle

Component	Inspection Items	Cycle
Pv Panel	Surface cleaning, Angle correction	Once a month
Battery	Voltage check (≥11.5V@12V)	Once a quarter
LED Luminaires	Lumen depreciation check (annual degradation <3%)	Once a year

6. Economic Analysis

1. Cost Comparison (based on 6m pole)

Item	Traditional Grid Lighting	LED Solar Street Light
Initial Investment	8,000 Yuan	12,000 Yuan
Annual Electricity Cost	600 Yuan	0 Yuan
Total Cost over 10 Years	14,000 Yuan	12,000 Yuan

Payback Period:

Payback Period = (Price Difference / Annual Savings) = (12,000 – 8,000) / 600 ≈ 6.7 years

7. Typical Cases

Project Name: New Rural Road Lighting

Parameters Configuration:

Road width 5m, staggered layout on both sides
LED power 60W × 2, luminous flux 9,000 lm/unit
Pv Panel 2 × 120W, battery 100Ah@24V

Performance Indicators:

Average illuminance 18 lx, uniformity 0.48
Continuous rainy backup 5 days
Annual energy-saving rate 100%

8. Risk Control

Over-discharge Protection: Controller sets voltage ≥10.8V (12V system).
Theft Protection: Photovoltaic panel bolts use irregular structures, battery case welded and fixed.
Extreme Weather: Photovoltaic panels hail resistance level ≥ Class 3 (25mm hail impact).

Appendix: Recommended Design Verification Tools

PVsyst (Photovoltaic system simulation)
DIALux evo (Lighting simulation)
Meteorological data sources: NASA POWER / China Meteorological Administration Radiation Stations

Through this guide, a systematic approach can be achieved from illumination requirements to economic returns, realizing a low-carbon and highly reliable road lighting solution.