Just want to power my bus lights and radio

[warleg]

I have a school bus that I have hard wired to my garage, but I would like to use the 12v lights on the outside and inside of the bus along with anything else that normally ran off the battery when it still had an engine in it. I have an extra 100w solar panel left over from my grid tied net metering system I had installed this spring. I want to use it to maintain the battery that used to be charged by the alternator. I can give more information about the battery if needed. Looking to find out what size solar charge controller to use, I'm going to mount the panel on the roof and mount the controller within ten feet of the panel and probably another ten feet to the battery. Thanks this is my first post hopefully I did okay.

 

[Supervstech]

A simple pwm controller should keep up the battery and the bus lights should not destroy the batteries. 100 watts will handle all but the headlights is think.

 

[Rider]

Replace the lights with low consumption LEDs, including the headlights, and the power you have will go much further.

 

[warleg]

A simple pwm controller should keep up the battery and the bus lights should not destroy the batteries. 100 watts will handle all but the headlights is think.

What amp would you recommend?

 

[offgriddle]

~ A 100 watt solar panel is going to generate about six amps of charging current in full sun, minus the minor losses in the short cables running from your solar panel and MPPT controller, then minus whatever losses are associated delivering the current to your mystery battery, I would count on about 5 amps per full sun hour that you can put into a battery. Now, it's your job to figure out how many lights you want to run, for how long and how much current the total of the lights added up will use per hour. Also, if your going to run a radio, you need to know about how much the radio is going to draw per hour and how many hours a day you want to run it.
~ Ways to get the most bang out of your solar panel: Position the panel for the best degree of tilt and direction to maximize solar gain, use LED lights as mentioned above, go with the MPPT solar charge controller instead of the PWM and if you do not have a battery and if the space where your battery is located will never drop below freezing, you would get the most power out of a lithium ion phosphate battery instead of lead acid based batteries.

 

[warleg]

~ A 100 watt solar panel is going to generate about six amps of charging current in full sun, minus the minor losses in the short cables running from your solar panel and MPPT controller, then minus whatever losses are associated delivering the current to your mystery battery, I would count on about 5 amps per full sun hour that you can put into a battery. Now, it's your job to figure out how many lights you want to run, for how long and how much current the total of the lights added up will use per hour. Also, if your going to run a radio, you need to know about how much the radio is going to draw per hour and how many hours a day you want to run it.
~ Ways to get the most bang out of your solar panel: Position the panel for the best degree of tilt and direction to maximize solar gain, use LED lights as mentioned above, go with the MPPT solar charge controller instead of the PWM and if you do not have a battery and if the space where your battery is located will never drop below freezing, you would get the most power out of a lithium ion phosphate battery instead of lead acid based batteries.

Will freeze and won't get used much in the winter, minibike storage and playhouse. lights will only get played with at most a couple times a month. debating if I'd be better off just using a battery tender? Just kinda wanted to use the solar panel for something lol

 

[offgriddle]

OK, then a lithium ion phosphate battery is out and if you hook up your solar panel directly to the mystery battery without any type of charge controller, not only could you overcharge and damage or ruin the mystery batttery, but unless you go to rat shack , (RIP Rat Shack), and purchase the right value of diode and place it in the right direction in the 12 volt positive line leading from your battery to your solar panel, the battery will back feed out to the solar panel at night and discharge! How bout just a simple grid battery charger that you can switch from float when your not using the battery in winter to a more aggressive level of charging when you want to run all of the lights and play Led Zepplin at full volume in the summertime? What to do with the panel you may still be wondering, maybe you can hook it up to a charge controller to maintain your battery?

 

[warleg]

OK, then a lithium ion phosphate battery is out and if you hook up your solar panel directly to the mystery battery without any type of charge controller, not only could you overcharge and damage or ruin the mystery batttery, but unless you go to rat shack , (RIP Rat Shack), and purchase the right value of diode and place it in the right direction in the 12 volt positive line leading from your battery to your solar panel, the battery will back feed out to the solar panel at night and discharge! How bout just a simple grid battery charger that you can switch from float when your not using the battery in winter to a more aggressive level of charging when you want to run all of the lights and play Led Zepplin at full volume in the summertime? What to do with the panel you may still be wondering, maybe you can hook it up to a charge controller to maintain your battery? View attachment 1447

LOL, never thought about hooking it up directly, I was pondering using my 110 service that I already have run to the bus to power a battery charger/tender that would maintain it and play all my hippie music! lol

 

[offgriddle]

LOL, never thought about hooking it up directly, I was pondering using my 110 service that I already have run to the bus to power a battery charger/tender that would maintain it and play all my hippie music! lol

Sounds like thats your best bet! Maybe you can find an off grid hippie, (who else would be off grid?), and you can trade for perhaps a woven basket or a lightly used tye dye shirt perhaps a dream catcher and some organic elderberry jam?

 

[BoloMKXXVIII]

Simple PWM charge controllers can be had for only a few dollars. That is all you need for your very basic setup.
I.e. : https://www.amazon.com/EEEKit-Contr...ements=p_72:2661618011&rnid=2661617011&sr=8-8

 

[eddie1261]

Sounds like thats your best bet! Maybe you can find an off grid hippie, (who else would be off grid?), and you can trade for perhaps a woven basket or a lightly used tye dye shirt perhaps a dream catcher and some organic elderberry jam?

I'd pass on the brownies though.....

 

[offgriddle]

I'd pass on the brownies though.....

THAT would be a very wise decision, man.