Help needed for photovoltaic systems

[exodia]

Hello there and nice to find you guys

I want your help into making a start studying photo voltaic system. The department i work is starting making studies about LED street lighting that will be power by PB panels, so i need something to start

Can we make a talk on what to watch out for, what panels to use in proportion with the DC loads i got, and stuff like that

In the application we will not use inverters, the DC will supply the LED circuits

[chromei386]

Some key issues I see arising are:

How many LEDs and what type will it take to provide adequate lighting (if these are for replacements for normal street lights).  What is the lighting requirement, is there any benchmark?

What is the power drain?

How will you store the energy  - SLA batteries? NiMH? NiCd? How long will they be able to provide lighting at load requirements?

What are your weight requirements? (Large SLAs are heavy, and could pose a danger if up high).

What is your backup plan, if there is no sun for days. Do you feed from the grid?

[Hero999]

It depends on what kind of streetlighting system is already in place. It could be possible that LEDs are inferior to the existing system, for example I know that low pressure sodium lamps are the most efficient light source known and that LEDs are much less efficient. There again, I think that doesn't account for the fact that the dark adapted human eye is more sensitive to shorter wavelengths so I can't be sure.

[exodia]

Hello again sorry for the delayed response

@chromei386

Power drain depends, thats why i want to be able to make some studies
We will store energy at gel batteries and we need them for 3 days reserve. About 9 hours a day

No feed from the grid ATM