Better Solar Path Lights?

[nezz621]

Last year I bought quite a few solar path and garden lights some of which have been a nice addition and others that look dim and cheap. This year i'd like to upgrade to something more impressive/useful while also learning about solar since i eventually want to buy a grid tie system for my entire home. What id like is a DIY outdoor solar setup that will provide more power and be able to utilize more lumens for my path/garden lights. I will probably also use some spot lights and retaining wall lights as well as long as this works according to plan.

So my question is does anyone have experience with building a custom setup that would provide more power than those tiny solar garden lights?

I'm thinking of using something along the lines of a 30 watt solar panel wired to an led driver, charge controller and battery connected to better quality lights.

Let me know what you guys think, and thanks in advance for the replies.

[inetdog]

I'm thinking of using something along the lines of a 30 watt solar panel wired to an led driver, charge controller and battery connected to better quality lights.
Let me know what you guys think, and thanks in advance for the replies.

Often the only really under-designed parts of the low quality lights are the panels and batteries. Of course some just corrode to nothing too, but that you can look for initially. The mechanically good ones can be improved by adding a better battery and a better (maybe mounted near instead of on the light) panel.

Since you are on-grid, the main reasons to go for solar powered outdoor lighting are:
1. To impress your friends (also called the Awesomeness Factor), and
2. Because you cannot run grid power, even at 12 volts AC, to where you want the light.

If you go to a central system, you are completely losing advantage number 2, unless you have a compact garden or lounging area which is a long way from power.
Even for larger lights (larger in a relative sense) a setup with a panel and battery per light will usually work better. Or else go to AC.

People often underestimate the size of panel and battery that will be needed for a substantial (3-4 watt) LED fixture. Just to calibrate the discussion, a 3 watt LED run at maximum output with a good reflector, can give you a beam brighter (over a limited area) than the headlights of your car.

[nezz621]

Wouldn't a panel and extra batteries per light be more expensive than a single panel and battery to power a few lights?

Also, would upgrading the battery and panel create a noticeable increase in lumens.


My though is that lights made for a 12 volt system ( that i would power via solar)would produce more lumens than solar lights.


What is the disadvantage of using one big battery and panel for multiple lights other than additional wiring?

[green]

I've been experimenting with this, and I've found that if your going for the most bang for the buck you want to use Grid power. My low voltage light system is the best part of my outdoor lighting. The solar stuff just adds to it. What I've been doing lately is waiting for the solar lights to go on clearance sale. Just tonight I picked up 4 lights at Home Depot that retail at $11 each, they were on sale for $2. I would've never paid full price for them, but at that price it's hard to pass up.

I've run the number on doing just a small solar powered low voltage system and it's crazy how much panel and battery it would take.

[green]

What is the disadvantage of using one big battery and panel for multiple lights other than additional wiring?

One major disadvantage is cost. Use that money for more lights and better lights on a 12 volt system and only pay $0.11/Kwh for the electricity from the POCO.

[nezz621]

I've run the number on doing just a small solar powered low voltage system and it's crazy how much panel and battery it would take.

Any more specifications on this subject?

I was only planning on getting around a 30 watt panel and figured i would power what i could with it until i decided to upgrade down the line. Would the 30 watts be adequate for a small setup with a few path lights and garden lights?

[nezz621]

One major disadvantage is cost. Use that money for more lights and better lights on a 12 volt system and only pay $0.11/Kwh for the electricity from the POCO.

unfortunately i live in Massachusetts and my electricity costs roughly $0.18/Kwh

Also I like the idea of doing this as a solar project for a reason to help me learn more about solar power.

[inetdog]

unfortunately i live in Massachusetts and my electricity costs roughly $0.18/Kwh

Also I like the idea of doing this as a solar project for a reason to help me learn more about solar power.

As an educational project, you can certainly justify it. But one of the things that you will learn is that if you include battery replacement and all other costs over the long haul you will be paying about $1.00 or more per kWh. That is higher than $.18 too.

[green]

Any more specifications on this subject?

I was only planning on getting around a 30 watt panel and figured i would power what i could with it until i decided to upgrade down the line. Would the 30 watts be adequate for a small setup with a few path lights and garden lights?

Search this forum for the Off Grid Calculator. You can play around with it to see what is possible. For example just running 60 Watts for 5 Hours a day would require 220 watts of panel with a PWM controller and 150Ah battery at 12V. It's a very cool tool.

[nezz621]

Search this forum for the Off Grid Calculator. You can play around with it to see what is possible. For example just running 60 Watts for 5 Hours a day would require 220 watts of panel with a PWM controller and 150Ah battery at 12V. It's a very cool tool.

I checked the grid calculator and found it very informative At this point I may end up going with a full DIY 5 kwh system. Thanks for the help everyone