Calculating Formula of Solar Street Lamp Configuration

一：首先計算出電流：

Firstly, the current is calculated.

如：12V蓄電池系統；30W的燈2只，共60瓦。

Such as: 12V battery system; 30W lamp 2, a total of 60 watts.

電流＝60W÷12V＝5A

Current = 60W_12V = 5A

二：計算出蓄電池容量需求：

Second: Calculate the battery capacity requirements:

如：路燈每夜累計照明時間需要為滿負載7小時（h）；

For example, the cumulative lighting time of street lamps per night should be 7 hours (h) of full load.

（如晚上8：00開啟，夜11：30關閉1路，凌晨4：30開啟2路，凌晨5：30關閉）

(If it opens at 8:00 p.m., closes Road 1 at 11:30 p.m., opens Road 2 at 4:30 a.m., and closes at 5:30 a.m.)

需要滿足連續陰雨天5天的照明需求。（5天另加陰雨天前一夜的照明，計6天）

It is necessary to meet the lighting requirement of 5 consecutive rainy days. (5 days plus overnight lighting on rainy day for 6 days)

蓄電池＝5A×7h×（5＋1）天＝5A×42h＝210AH

Battery=5A*7h*5+1 days=5A*42h=210AH

另外為了防止蓄電池過充和過放，蓄電池一般充電到90％左右；放電余留20％左右。所以[FS:PAGE]210AH也只是應用中真正標準的70％左右。

In addition, in order to prevent the battery from overcharging and overdischarging, the battery is generally charged to about 90%, and the remaining discharging is about 20%. So [FS: PAGE] 210AH is only about 70% of the real standard in application.

三：計算出電池板的需求峰值（WP）：

Third: Calculate the peak demand of battery panel (WP):

路燈每夜累計照明時間需要為7小時（h）；

The cumulative lighting time of street lamps per night is 7 hours (h).

★：電池板平均每天接受有效光照時間為4.5小時（h）；最少放寬對電池板需求20％的預留額。

: The average daily effective illumination time for the panels is 4.5 hours (h); at least the 20% reserve for the requirements of the panels should be relaxed.

WP÷17.4V＝（5A×7h×120％）÷4.5h

WP_17.4V=(5A*7h*120%) and_4.5h

WP÷17.4V＝9.33

WP_17.4V=9.33

WP＝162（W）

WP = 162 (W)

★：4.5h每天光照時間為長江中下游附近地區日照系數。長江中上游一般為5h。

: The daily sunshine time of 4.5 hours is the sunshine coefficient near the middle and lower reaches of the Yangtze River. The upper and middle reaches of the Yangtze River are generally 5 hours.

另外在太陽能路燈組件中，線損、控制器的損耗、及鎮流器或恒流源的功耗各有不同，實際應用中可能在5％-25％左右。所以162W也只是理論值，根據實際情況需要有所增加。

In addition, in the solar street lamp module, line loss, controller loss, and power consumption of ballast or constant current source are different, which may be about 5% - 25% in practical application. So 162W is only a theoretical value, which needs to be increased according to the actual situation.