Hack#22 - Solar panel for lighting

1. ©drtamil@gmail.com 2017
Automatic Porch Light
using Solar Power.

2. ©drtamil@gmail.com 2017
Objective
• Having a porch light that switches on at dusk
and switches off at dawn, automatically.
• Powered by a single solar panel.

3. ©drtamil@gmail.com 2017
Item 1 – Solar panel 12V 10W
• https://www.lazada.com.my/12v-10w-watt-
polycrystalline-cells-solar-panel-poly-solar-
module-battery-charger-13254147.html
• RM93• RM93

4. ©drtamil@gmail.com 2017
Cheaper – Solar panel 12V 10W
• http://www.lazada.com.my/10-watt-10w-
polycrystalline-solar-panel-12v-ready-stock-
28045065.html
• RM76 – no longer available• RM76 – no longer available

5. ©drtamil@gmail.com 2017
Item 2 – Solar Charge Controller
• https://www.lazada.com.my/dual-usb-pwm-
102030a-solar-charge-controller-12v24v-lcd-
displaysolar-panel-charge-regulator-
models10a-83267837.htmlmodels10a-83267837.html
• RM34.70

6. ©drtamil@gmail.com 2017
Item 3 – 12V 7.2Ah GP Battery
• https://www.lazada.com.my/genuine-gp-12v-
72ah-rechargeable-sealed-lead-acid-battery-
gpp1272-29285514.html
• RM60• RM60

7. ©drtamil@gmail.com 2017
Item 4 – 12V White Light Bulb
• https://www.lazada.com.my/e27-5w-6000k-
led-bulbs-lamp-for-dc-12vwhite-light-
101540546.html
• RM14.20• RM14.20

8. ©drtamil@gmail.com 2017
Cost
Items Price
Solar panel 12V 10W RM93.00
Solar charge controller RM34.70
GP 12V 7.2Ah Battery RM60.00
12V DC White Light Bulb RM14.20
• Not inclusive of labour,
wiring, conduit &
installation charges.
TOTAL RM201.90

9. ©drtamil@gmail.com 2017
Calculating The Load
Power for Bulb 12V 5W
• Dusk to dawn = 12 hours.
• 12 hours x 5 Watt = 60WH.
Power from 12V 7.2Ah Battery
• 7.2Ah x 12V = 86.4WH
• Being a sealed lead acid
battery, you get only 50% of
that power.
• 86.4WH x 0.5 = 43.2WH• 86.4WH x 0.5 = 43.2WH
(<60WH; inadequate)
• If 12V 12Ah;
12Ah x 12V = 144 WH
50% would be 72WH. Enough.
• https://www.lazada.com.my/
genuine-gp-12v-12ah-
rechargeable-sealed-lead-acid-
battery-gpp12120-
96324854.html (RM129.50)
Power from Panel 12V 10W
• Dawn to dusk = 12 hours.
• Kuala Lumpur Daily Daylight
Average = 6 hours
• 6 hours x 10 Watt = 60WH.
• So 1 solar panel 12V10W
can generate enough power
for one 12V5W bulb.

10. ©drtamil@gmail.com 2017
The Installation
Solar panel on
roof top.
Solar panel on
roof top.
Wiring from
solar panel to
solar charge
controller.
Wiring from
solar panel to
solar charge
controller.
roof top.roof top.
Solar charge controller.Solar charge controller.
Solar charge controller.Solar charge controller.
12V bulb12V bulb
12V battery12V battery

11. ©drtamil@gmail.com 2017
Connecting Everything – Step 1
1. Connect battery to
solar charge controller.
It will detect the type
of battery.
1. Connect battery to
solar charge controller.
It will detect the type
of battery.

12. ©drtamil@gmail.com 2017
Connecting Everything – Step 2
2. Connect solar
panel to solar
charge controller.
It will detect the
type of solar
panel.
2. Connect solar
panel to solar
charge controller.
It will detect the
type of solar
panel.

13. ©drtamil@gmail.com 2017
Connecting Everything – Step 3
3. Connect light
bulb to solar
charge controller.
3. Connect light
bulb to solar
charge controller.

14. ©drtamil@gmail.com 2017
Connecting Everything – Step 4
4. Click on this
button 4x until
you get this work
mode display.
4. Click on this
button 4x until
you get this work
mode display.

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Connecting Everything – Step 5
5. Then press on
this button for 5
seconds until it
starts blinking.
5. Then press on
this button for 5
seconds until it
starts blinking.

16. ©drtamil@gmail.com 2017
Connecting Everything – Step 6
6. Then click on this + button
once so that it displays “00”.
Then the light will switch on
from dusk to dawn. “24” means
that it will be on 24 hours. You
can set from “00” to “24”.
6. Then click on this + button
once so that it displays “00”.
Then the light will switch on
from dusk to dawn. “24” means
that it will be on 24 hours. You
can set from “00” to “24”.

17. ©drtamil@gmail.com 2017
Connecting Everything – Step 7
7. Then click on this
button once to save
the setting. Now
you’re done.
7. Then click on this
button once to save
the setting. Now
you’re done.

18. ©drtamil@gmail.com 2017
Conclusion
• As expected I couldn’t get the light to run from
dusk to dawn due to the wrong capacity of the
battery. I should have bought the 12V12Ah
battery instead of the 12V7.2Ah battery. Wrongbattery instead of the 12V7.2Ah battery. Wrong
advice received.
• I should cover back the cost of my investment
within 100 days of use. It should last for 2 years.
• The light was bright enough to illuminate the
porch.