Calculation Method for Battery Capacity Allocation of Solar Street Lights

The role of special batteries for solar street lights in solar street light is beyond doubt. The rationality of battery capacity configuration directly determines the use effect of solar street lamps. Let's first understand the working principle of solar street lights: solar street lights are composed of 5 parts as a whole, including solar panels, LED light sources, special solar batteries, controllers, and solar panels that absorb solar light and convert light energy into electrical energy. The control of the device is stored in the solar battery. When lighting at night, the controller controls the solar battery to supply power to the LED light source according to the light control and time control settings.

The capacity of the battery is very important to ensure continuous power supply. During the year, the amount of electricity generated by solar panels varies greatly from month to month. In the months when the power generated by solar panels cannot meet the electricity demand, it depends on the electric energy of the battery to make up for it; in the month that exceeds the electricity demand, it relies on the battery to store the excess electricity.

Calculation of battery capacity (take 24V40W solar street light as an example)

1. LED lights, single channel, 40W, 24V system.

2. The local daily average effective light is calculated as 4 hours,

3. The daily discharge time is 10 hours, (take 7:00 p.m.-5:00 a.m. as an example) through the controller at night

Adjust the power of LED lamps in time intervals to reduce the total power consumption, and the actual calculation is based on 7 hours of discharge per day.

(Example 1: 100% power from 7:00 pm to 11:00 am, 50% power from 11:00 am to 5:00 am. Total: 7h)

(Example 2: 7:00-10:30 is 100%, 10:30-4:30 is 50%, 4:30-5:00 is 100%)

4. Satisfy 5 consecutive days of rainy days (plus the power consumption of the night before the rainy day, counting as 6 days).

Current: 40W÷24V=1.67A

Calculation battery : 1.67A × 7h × (5+1) days=1.67A×42h=70AH

Reserve 20% capacity for charging and discharging the battery; the actual current of the street lamp is above 2A (plus 20% loss, including constant current source, line loss, etc.)

Actual battery demand = 70AH plus 20% reserved capacity, plus 20% loss

70AH÷80%×120%=105AH

The actual battery is 24V/105AH, and a single battery is generally 12V, so it is necessary to match two 12V100AH or two 12V120AH solar street light batteries in series to form a battery pack to supply power for solar street lights.

After the above reasonable calculations, it is concluded that the solar battery capacity configuration can meet the lighting time and lighting effect of solar street lights. If you don't know how much battery capacity your outdoor solar street light needs, or you don't know how to choose the right solar energy for your parking lot or street, Hishine Group Limited will provide you with professional advice and high-quality products.