Calculate Street Light Pole’s Distance / Fixture Watt / Lighting Area

(1) Calculate Distance between each Street Light Pole:

Example: Calculate Distance between each streetlight pole having following Details,

  • Road Details: The width of road(w) is 11.5 Foot.
  • Pole Details: The height of Pole is 26.5 Foot.
  • Luminaire of each Pole: Wattage of Luminaries is 250 Watt, Lamp Out Put (LL) is 33200 Lumen, Required Lux Level (Eh) is 5 Lux, Coefficient of Utilization Factor (Cu) is 0.18, Lamp Lumen Depreciation Factor (LLD) is 0.8, Lamp Lumen Depreciation Factor (LLD) is 0.9.
  • Space Height Ratio should be less than 3.


  • Spacing between each Pole=(LL*CU*LLD*LDD) / Eh*W
  • Spacing between each Pole=(33200×0.18×0.8×0.9) / (5×11.5)
  • Spacing between each Pole= 75 Foot.
  • Space Height Ratio = Distance between Pole / Road width
  • Space Height Ratio = 3. Which is less than define value.
  • Spacing between each Pole is 75 Foot.

(2) Calculate Street Light Luminaire Watt:

Example: Calculate Streetlight Watt of each Luminaire of Street Light Pole having following Details,

  • Road Details: The width of road(w) is 7 Meter. Distance between each Pole (D) is 50 Meter.
  • Required Illumination Level for Street Light (L) is 6.46 Lux per Square Meter. Luminous efficacy is 24 Lumen/Watt.
  • Maintenance Factor (mf) 0.29, Coefficient of Utilization Factor (Cu) is 0.9.


  • Average Lumen of Lamp (Al) = 8663 Lumen.
  • Average Lumen of Lamp (Al) =(LxWxD) / (mfxcu)
  • Average Lumen of Lamp (Al)= (6.46x7x50) / (0.29×0.9)
  • Average Lumen of Lamp (Al)=8663 Lumen.
  • Watt of Each Street Light Luminar = Average Lumen of Lamp / Luminous efficacy
  • Watt of Each Street Light Laminar = 8663 / 24
  • Watt of Each Street Light Luminaire = 361 Watt

(3) Calculate Required Power for Street Light Area:

Example: Calculate Streetlight Watt of following Street Light Area,

  • Required Illumination Level for Street Light (L) is 6 Lux per Square Meter.
  • Luminous efficacy (En) is 20 Lumen per Watt.
  • Required Street Light Area to be illuminated (A) is 1 Square Meter.


  • Required Streetlight Watt = (Lux per Sq.Meter X Surface Area of Street Light) / Lumen per Watt.
  • Required Streetlight Watt = (6 X 1) / 20.
  • Required Streetlight Watt = 0.3 watt per Square Meter.

About Jignesh.Parmar
Jignesh Parmar has completed M.Tech (Power System Control), B.E(Electrical) from Gujarat University. He has more than 13 years experience in Power Transmission-Power Distribution-Electrical energy theft detection-Electrical Maintenance-Electrical Projects(Planning-Designing-coordination-Execution). He is Presently associate with one of the leading business group as a Deputy Manager at Ahmedabad,India. He is Freelancer Programmer of Advance Excel and design useful Excel Sheets of Electrical Engineering as per IS,NEC,IEC,IEEE codes. He is technical Author for "Electrical Mirror" and "Electrical India" Magazines. He is Technical Blogger and Familiar with English, Hindi, Gujarati, French languages. He wants to Share his experience & knowledge and help technical enthusiasts to find suitable solutions and updating themselves on various Engineering Topics.

21 Responses to Calculate Street Light Pole’s Distance / Fixture Watt / Lighting Area

  1. Panneer SELVAM (ETS Limited, Dubai) says:

    Your sincere effort and goodwill contribution are to be thanked at all times.

    Paneer Selvam | Manager (Marketing)

    Emirates Transformer & Switchgear Limited

    Jebel Ali | Dubai | United Arab Emirates

  2. I acknowledge the hard efforts of sharing thoughts among all educators, scientists of Mr. Jignesh Parmar, see my thoughts for all educators: We all remain as students in our short life on this world?

    Helping others (students) to develop a deep love and respect for themselves, others, and their environment occurs through an open sharing of ideas and a judicious approach to discipline. When the voice of each student is heard, and environment evolves where students feel free to express themselves. Class meetings are one way to encourage such dialogue. I believe children have greater respect for their teachers, their peers, and the lessons presented when they feel safe and sure of what is expected of them. In setting fair and consistent rules initially and stating the importance of every activity, students are shown respect for their presence and time. In turn they learn to respect themselves, others, and their environment.

    • DWIGHT R. MACHICA says:

      thanks for the knowledge shared to us and it is very useful refference on how to calculate or computation for the street light proper engineering works

  3. Prasad Jose says:

    It seems so informative for the engineers especially electrical engineers for their practical knowledge improvement and of course for the timely help for urgent reference..

  4. Mariegold says:

    very useful information. but i will like to ask, what if u were not given the illuminance, but u were given the intensity, area served and efficacy, how do u find the power, based on an operation of 12hrs per day?

  5. Tabish Hilal says:

    It is Really helped me in real time calculation.

  6. Thet says:

    Thank you so much for your sharing.

  7. Juma Ganiyu says:

    Very helpful

  8. Juma Ganiyu says:

    I have 8m pole and the distance between one pole to the next is 50m, the width of the road is 30m. I want to find the wattage of the LED lamp that will give the max illumination. HOW DO I GET IT. Please help me..

  9. Dear sir ,i need simple calculation of indoor lighting lux design.

  10. AbduRahman Yusuf says:

    When a number of Single phase loads are powered/fed through a TPN DB. How do we get/calculate the Three Phase Total Loading of the DB, especially to aid sizing of the DB’s 3-Phase Main Breaker and Feed Cable selection?

  11. Sunil says:

    Height of high mast is 16 meter, The area of ground 85000 sq meter (340 meter long and 250 meter wide). Please suggest me, how much high mast will be installed and no. of lamps with wattage and type.

  12. ONASIS says:


  13. Jagadeesh says:

    My road width is 5Mts,Distance between poles 20Mts,height o pole is 8mts
    What LED i can use for this application

  14. Jagadeesh says:

    Any post regarding LED selectio.Will be helpful

  15. Anupam Saha says:

    can anybody please guide me regarding how much wattage of LED will be suficient for a 16 metre height highmast?

  16. Shiv Kumar says:

    Dear Sir ,

    when you have calculated the spacing between each pole in that case why you use same factor in two time :- Lamp Lumen Depreciation Factor (LLD) is 0.8, Lamp Lumen Depreciation Factor (LLD) is 0.9 .

    I think another one will be – Light Loss Factor


    Shiv Kumar

  17. dinesh kumar says:

    please let me know the distance between high mast light and residential buildings

  18. Nazari says:

    Please provide us with solar street lighting design, what is the average lux requirement for road lighting? which codes can I refer to?

  19. Gurvinder Pal Singh says:

    The width of Street is 4m.25watt led is proposed in the street.What should be the height of pole to achieve lux level as per norms in C type roads.

  20. kunal says:

    i have 50 watt street light of 140 lm/watt .so please send how much area it will cover. if i will mount it at 15ft,20ft,25ft.

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