Outdoor Display Light System Help

[oiyela]

Hi,
I am trying to build an outdoor display which will light up at night using LED lights which will be powered by a solar battery. I need some help on how to set it up and what will be needed.

The display will have a solar panel on the top of the display and also have a battery as well. During the day the battery will charge and in the night the lights will be powered by the stored energy in the battery. I need to know if there are any off the shelf light sensor that i can get to power the lights at night. Can someone please suggest how i can set up the whole system. Do i need a solar controller as well for the system. I also need these system to be small and cost effective if possible. Any suggestion is welcome.

 

[betwixt]

Those questions need more information. Are you talking about solar lights to mark a path in a garden or are you trying to provide lighting to a tower block of offices. Scale makes a big difference to the answer and technologies needed.

Brian.

 

[oiyela]

Those questions need more information. Are you talking about solar lights to mark a path in a garden or are you trying to provide lighting to a tower block of offices. Scale makes a big difference to the answer and technologies needed.

Brian.

Hi,
Thank you for your reply. We have a total power consumption of 50W. We will need the lights to be on for 12 hours in a day. I am thinking of using a 100W or 200W solar panel but we are restricted to a surface space of 1.35M by 0.665M . I want the light to come on at 6pm and off at 6am, the battery will charge when the lights are not on. What devices will i need to make this happen. Please help if you can.

 

[Audioguru]

There is an advertising sign in a field at the edge of town. Electricity wiring would cost a fortune to connect to it so the owner installed a solar panel and a battery. It worked fine in the evening of a sunny day but did not work following a cloudy day. So he replaced the solar panel with a windmill. Some calm days it also does not charge the battery.

There is a shopping mall near my home that has a timer turn on the parking lot lights at 6PM and turn them off at 6AM. In winter it is dangerous for people walking to their cars to have no lights when the sun sets at about 4:30PM until the lights turn on. In the summer it is funny to see the lights turn on hours before the sun sets at about 9:30PM.

My solar garden lights have the solar panels pointing straight up. The sun is almost straight up in summer but is low in the sky in winter. The lights barely work at night in the winter and I doubt the low temperature has anything to do with it.

 

[oiyela]

There is an advertising sign in a field at the edge of town. Electricity wiring would cost a fortune to connect to it so the owner installed a solar panel and a battery. It worked fine in the evening of a sunny day but did not work following a cloudy day. So he replaced the solar panel with a windmill. Some calm days it also does not charge the battery.

There is a shopping mall near my home that has a timer turn on the parking lot lights at 6PM and turn them off at 6AM. In winter it is dangerous for people walking to their cars to have no lights when the sun sets at about 4:30PM until the lights turn on. In the summer it is funny to see the lights turn on hours before the sun sets at about 9:30PM.

My solar garden lights have the solar panels pointing straight up. The sun is almost straight up in summer but is low in the sky in winter. The lights barely work at night in the winter and I doubt the low temperature has anything to do with it.

Hi,
Thank you very much for your story, very interesting. This set up is for an advertising sign and it is going to be implemented in a country that does not have winter, Its a tropical country. Hope you can help contribute to the project.

Best Regards,

 

[betwixt]

It's a huge advantage when the Sun passes almost overhead every day. Audioguru is about 43 degrees north and I'm about 52 degrees north and hence the Sun is never very high in the sky and for half the year the daylight hours are shorter than night. It puts a different perspective on photovoltaics and changes the way we use them.

Assuming you can generate enough electricty, the next questions are:

1. how accurate does the timing have to be?
2. Does your country use daylight savings time? (unlikely based on what you describe) It would mean the clock had to advance and retard an hour once each year.
3. Is there an alternative power source available or are you totally reliant on PV?

Brian.

 

[Venkadesh_M]

What type of displays you are having like DC LED or neon or something else?
what is the voltage of display ?
what is the power availability of solar panel size you mentioned?
you will just need a battery and some turn on mechanism thats all..

 

[oiyela]

It's a huge advantage when the Sun passes almost overhead every day. Audioguru is about 43 degrees north and I'm about 52 degrees north and hence the Sun is never very high in the sky and for half the year the daylight hours are shorter than night. It puts a different perspective on photovoltaics and changes the way we use them.

Assuming you can generate enough electricty, the next questions are:

1. how accurate does the timing have to be?
2. Does your country use daylight savings time? (unlikely based on what you describe) It would mean the clock had to advance and retard an hour once each year.
3. Is there an alternative power source available or are you totally reliant on PV?

Brian.

Hi Brian,
Thank you very much for your reply, greatly appreciated. The country does not use daylight saving time our time stays the same. I am based in Nigeria. The timer will have to be abit accurate because initially i wanted to used an LDR which will put the lights on automatically when it is dark but then i was thinking it might put the lights on longer and there will be periods of time were there won't be light. So i thought using a timer will be more efficient as i can ensure that at least for a set period of time the display of the advertising sign will be lit up. I am thinking of using energy saving LED bars which will total to 50W for one advertisement stand. There is no alternative power source available only the solar energy as the source. There will be about 30 advertisement signs spread across a road stretch of road.

Thanks

- - - Updated - - -

What type of displays you are having like DC LED or neon or something else?
what is the voltage of display ?
what is the power availability of solar panel size you mentioned?
you will just need a battery and some turn on mechanism thats all..

Hi,
Thanks for your reply. It is a DC LED, the voltage of the display will be about 12V, please find the link to

https://www.alibaba.com/product-detail/energy-saving-cheap-led-light-bars_1039448197.html

The 50W total light consumption, on for 13 hours, will take 50 x 13 = 650WH from the battery.

i am thinking of using a 100AH 12V battery
For a 100AH, 12V battery the Watt Hours figure is 100 x 12 = 1200WH

This means the battery could supply 1200W for 1 hour, or 600W for 2 hours

I am thinking of using a 100W solar panel

For the Solar 100W panel in 6 hours* of sunshine, 100 x 6 x 0.85 = 510WH. This is the amount of energy the Solar panel can supply to the battery.
(Please note 0.85 this factor allows for natural system losses).

 

[Venkadesh_M]

Then nearly you completed the project..

you can turn them ON and OFF using simple controller and relay. timing can can be controlled by RTC or without RTC.

also you can measure the battery voltage using controller.

but the deficiency in energy 650 - 510 will lead to some deficiency in ON time..

 

[betwixt]

You could also consider using both a clock and an LDR. For example you could make it operate at certain times only when it's dark or you could make it operate in darkness regardless of the time. It buys you some extra flexibility at little more cost.

Brian.

 

[Audioguru]

Is the power rating of the solar panel only at noon when the panel is pointing directly at the sun? It is much less in the morning and evening. Having the panel move and "follow" the sun across the sky increases its low output in the morning and evening.
Aren't there cloudy days in your country? Then the output from the solar panel is much less.

A Lead-acid battery is rated at 20 hours. Then a 100Ah battery can supply 5A for 20 hours and its datasheet shows how much less its discharge time will be at higher currents.