Solar street light offers frequently advertise impressive wattages without showing how long the lamp can operate at that power. For a municipal or EPC tender, the essential figures are actual LED input power, usable battery energy, solar generation and the nightly operating schedule. A quotation without these numbers cannot be compared fairly.
Start with measured LED input power
A marketing model number is not a substitute for electrical input power. Ask for the luminaire test report or a documented input-power measurement at the specified operating mode. Confirm whether the claimed wattage refers to the LED chips, driver input or a product family name.
For lighting quality, request photometric files and an illuminance or luminance calculation. A high advertised wattage does not establish adequate uniformity or low glare.
Convert battery capacity into watt-hours
Battery capacity is often stated in ampere-hours, but Ah alone is not enough. Nominal energy in watt-hours is nominal voltage multiplied by Ah. For example, a 25.6V, 40Ah pack contains 1,024Wh nominal energy; the usable portion depends on allowed depth of discharge, temperature and battery management limits.
Do not compare a 12.8V 40Ah battery with a 25.6V 40Ah battery as though they store the same energy. Ask for cell chemistry, nominal voltage, nominal Ah, BMS limits and battery test documentation.
Check the dimming profile and autonomy
An illustrative 40W light operating for six hours at full power and six hours at 30% draws 312Wh before system losses. Two nights of autonomy require at least 624Wh delivered to the LED, plus allowances for conversion losses and usable battery limits. Actual battery and PV sizing must use the project location and worst-month solar conditions.
Motion-sensor operation can reduce average energy consumption, but the tender must specify the assumed traffic pattern. A promise of twelve hours at 100% is different from twelve hours with deep dimming.
Ask for PV and battery evidence
- Rated LED input watts and photometric file.
- Battery chemistry, voltage, Ah, nominal Wh and usable Wh.
- Solar panel rated Wp, technology and mounting arrangement.
- Charge controller rating and operating limits.
- Nightly dimming schedule and expected operating hours.
- Autonomy requirement for cloudy weather and design month.
- Transport, safety and warranty documentation applicable to the actual components.
Avoid unsupported certifications
Ask suppliers for documents for the exact quoted model or component. Do not assume a logo on a catalogue proves that every configuration carries the same certification. Verify report identifiers and applicable market requirements before approving a tender.
Frequently Asked Questions
Is a 100W solar street light always consuming 100W?
No. The name may refer to a model or marketing rating; confirm measured input power and operating mode.
Can battery Ah be compared directly?
Only when the nominal voltage and usable energy assumptions are also known.
Does a bigger panel guarantee all-night operation?
No. PV yield, battery capacity, losses and the nightly load all matter.
Request a Project-Specific SUNLUX Quotation
SUNLUX Lighting supports project-based lighting and pole procurement. Share your site conditions, quantities, drawings or BOQ for a technical review. Email sales@sunluxledlighting.com or contact WhatsApp +8619189782897. Configuration, performance and certifications must be confirmed for the selected model.
Related SUNLUX guides: Solar charging and operating hours, Municipal solar procurement.
