Good solar panel brand?
I'm thinking of installing a solar panel on my Northern Lite 10.2. I'm looking for some advice on brand method of install. I have 2 grp. 24 batteries and an on board genny. I'm thinking of apx a 100 w...
Forum Discussion
In my simple thinking I run into the characteristics of what you are getting... The 100WATT solar panel you are wanting is probably rated as 18VDC output @ 5.5AMPS to get its 100WATT panel rating.
For you to re-charge a battery you will need the provided solar controller to give you something in the 14.4VDC range. This will probably end up being 14.4VDC@4-5 AMPs that is physically going to your battery terminals coming from a 100WATT solar panel when it is in the high sun period of the day. With 5AMPS output you are only getting 72WATTS of usable DC power from your 100WATT panel.
You will have to decide that is this enough power power to keep your to GP24 batteries charged up for the one day/night run off the batteries.
My simple thinking is a normal smart mode charging unit will recharge your two GP24 batteries back to their 90% charge state in a three hour period. Your smart mode converter/charger will produce 14.4VDC to get this charge state going. The bad news is the two GP24 batteries will demand around 40AMPS of charge current for a short time period to get to the 90% charge state in the three hour period. This 40 AMPS of charge current has to come from the smart mode converter/charger. After about 20 minutes or so the two GP24 batteries will drop down to demanding 5-6 AMPS until they get to their 90% charge state.
Using your new 100WATT SOLAR Panel you will only get 14.4VDC@ 5AMPS to get this 90% charge state going. When the two GP24 batteries demand the 40AMPS charge current only 5AMPS will be available. Your two GP24 batteries will charge ok with the 5AMPS charging current but it will not get to the 90% battery charge state in a short three hour period. It will take "MUCH" longer and most likely you will run out of available SUNLIGHT during the one day SUN WINDOW which is probably around 6-8HOURS long for high SUN.
This will be your short comings using the smaller solar panels in my opinion.
I too am just trying to plan out a solar install and not finding my situation is as black and white as alot folks seem to pass along.
My saving grace is I have been running my battery system camping off the power power grid for the past five years or more so I know what to expect from my batteries. I only have enough room on my off-road POPUP for three solar panels and am thinking two 120/130WATT panels on one end and hopefully I can afford maybe a 220WATT panel on the rear end of my roof. I suspect I will only get 14.4VDC@25AMPS (or around 360WATTS) from the solar controller for these three panels to recharge my battery bank with. This is a long way from the stated 460WATTS worth of solar panels... The big question for me is this going to be enough charge to re-charge my three 255AH battery bank back up to the 90% charge state during the high SUN time period of 6-8Hours. Probably going to be close haha... My daily battery consumption is consistently 300WATTS when camping off the power grid.
My other problem is I only have a short window to know for sure I will get to the required 90% charge state on my three batteries. I have to know by 4:30 each day if this is going to happen so that I can go to PLAN B and recharge for three hours using my 2KW Generator for three hours if it doesn't happen. Not having a 90% battery charge state each evening to start my run off the batteries is NOT an option for me. My trailer will get dark on me around 10PM at night and I can't run my generator until 8AM the next morning due to generator run time restrictions here on East side of the US.
Just passing all of this along to add to your thinking process of what you might need to be successful charging your batteries with your solar panels.
Will require some planing
Be sure to check out MELLO MIKE'S TC setup with his solar panels.
Roy Ken
For you to re-charge a battery you will need the provided solar controller to give you something in the 14.4VDC range. This will probably end up being 14.4VDC@4-5 AMPs that is physically going to your battery terminals coming from a 100WATT solar panel when it is in the high sun period of the day. With 5AMPS output you are only getting 72WATTS of usable DC power from your 100WATT panel.
You will have to decide that is this enough power power to keep your to GP24 batteries charged up for the one day/night run off the batteries.
My simple thinking is a normal smart mode charging unit will recharge your two GP24 batteries back to their 90% charge state in a three hour period. Your smart mode converter/charger will produce 14.4VDC to get this charge state going. The bad news is the two GP24 batteries will demand around 40AMPS of charge current for a short time period to get to the 90% charge state in the three hour period. This 40 AMPS of charge current has to come from the smart mode converter/charger. After about 20 minutes or so the two GP24 batteries will drop down to demanding 5-6 AMPS until they get to their 90% charge state.
Using your new 100WATT SOLAR Panel you will only get 14.4VDC@ 5AMPS to get this 90% charge state going. When the two GP24 batteries demand the 40AMPS charge current only 5AMPS will be available. Your two GP24 batteries will charge ok with the 5AMPS charging current but it will not get to the 90% battery charge state in a short three hour period. It will take "MUCH" longer and most likely you will run out of available SUNLIGHT during the one day SUN WINDOW which is probably around 6-8HOURS long for high SUN.
This will be your short comings using the smaller solar panels in my opinion.
I too am just trying to plan out a solar install and not finding my situation is as black and white as alot folks seem to pass along.
My saving grace is I have been running my battery system camping off the power power grid for the past five years or more so I know what to expect from my batteries. I only have enough room on my off-road POPUP for three solar panels and am thinking two 120/130WATT panels on one end and hopefully I can afford maybe a 220WATT panel on the rear end of my roof. I suspect I will only get 14.4VDC@25AMPS (or around 360WATTS) from the solar controller for these three panels to recharge my battery bank with. This is a long way from the stated 460WATTS worth of solar panels... The big question for me is this going to be enough charge to re-charge my three 255AH battery bank back up to the 90% charge state during the high SUN time period of 6-8Hours. Probably going to be close haha... My daily battery consumption is consistently 300WATTS when camping off the power grid.
My other problem is I only have a short window to know for sure I will get to the required 90% charge state on my three batteries. I have to know by 4:30 each day if this is going to happen so that I can go to PLAN B and recharge for three hours using my 2KW Generator for three hours if it doesn't happen. Not having a 90% battery charge state each evening to start my run off the batteries is NOT an option for me. My trailer will get dark on me around 10PM at night and I can't run my generator until 8AM the next morning due to generator run time restrictions here on East side of the US.
Just passing all of this along to add to your thinking process of what you might need to be successful charging your batteries with your solar panels.
Will require some planing
Be sure to check out MELLO MIKE'S TC setup with his solar panels.
Roy Ken
