Solar battery charger for tractor

[dan_m]

Just curious why you didn't go with larger panels and battery bank (especially since you mentioned running LED lights? Obviously there's a larger upfront cost for batteries + panel + charge controller + inverter (if you're not running all 12v).

I have a shed that I have 2 x 100Ah AGM batteries (100Ah usable) + MPPT inverter + 100w panel (I'll upgrade to 200 watts soon so I can power some LED landscape lighting using the port on the controller so they will come up when panel stops charging and go off when panel starts charging). I also opted for 110v motion security light (you can do 12v motion + 12v lights) + i have an LED shop light that lights up the entire shed.

in winter (only 4 hours light most days, not all) current setup stays at 12.4-12.5v. In summer with more sun, stays closer to 13v.

Also, if you decide to move to roof, you can get port designed for rv/boats that will seal out environment but allow cables in (seen single, double and triple).

Nice setup!

I have a trickle solar charger attached to my old lawn mower (use for bagger). The my bx2380 stays in the garage and I use it year round so no need for trickle charger.

Dan

 

[GreensvilleJay]

kinda curious...
re: I have 2 x 100Ah AGM batteries (100Ah usable)

why only 1/2 usable ?

 

[dan_m]

kinda curious...
re: I have 2 x 100Ah AGM batteries (100Ah usable)

why only 1/2 usable ?

Nature of AGM (and lead acid) batteries. Lithium batteries (which are way more expensive) can generally discharge between 90 and 95% whereas AGM batteries can typically handle up to 50%. Using an app for the controller which has a blue tooth module, I can check the voltage. for AGM batteries I have, 50% depleated is 12.05v. Running below this can damage the batteries and cause pre-mature failure. I got a chart from the battery manufacture showing voltage vs charge level (100% = 13V, 0% = 10.5V)

Therefore , when looking at a 100Ah AGM battery, it really is 50% usable so 50Ah of run-time. This is the calculation I use when I determine my power usage (lights, inverter, etc).

When I ordered my batteries, it was about $400 for 100Ah total usable power (2x100Ah AGM batteries) vs over 600 for 100Ah lithium iron. For me it was cost. Also means, I need to pay more attention to the voltage and not allow it to get depleted.

Now that I want to run more lights (12v landscape), I'm going to add more batteries (I actually will probably do 2nd panel & charge controller with 2nd battery bank so I can point the panels in different directions (it's been about a year so I now know where sun shines during what part of year). This will allow me to get the most sunlight during the entire year. In summer, where my current panel is at will power everything, however, in fall, it won't be able to keep the existing batteries charged. My shed is at woodline across creek and with angle of sun, to get most sun year round, 1 panel needs to point south and one panel to point more westward. in fall/winter, the westward panel gets 3-4 hours sunlight but closer to 7 in summer (maybe more).


Hope this explains it.

Dan

 

[GreensvilleJay]

thanks for the info ! Good someone reads the 'fine print' about their batteries !! 3 decades ago I used a lot of Gates SLA batteries, good enough for nuke subs , great for me. Gates sent me about 50# of documentation so I could maximize the life of the batteries.

 

[dan_m]

thanks for the info ! Good someone reads the 'fine print' about their batteries !! 3 decades ago I used a lot of Gates SLA batteries, good enough for nuke subs , great for me. Gates sent me about 50# of documentation so I could maximize the life of the batteries.

It's good that some companies do provide good information and don't force users into situations where they unknowingly cause issues and force them to buy new products. Unfortunately customer service isn't a high priority for some companies- those that do are where I like to spend my money.

Dan

 

[Vigo]

When I ordered my batteries, it was about $400 for 100Ah total usable power (2x100Ah AGM batteries) vs over 600 for 100Ah lithium iron

You might be happy to know that the cheapest going rate for 100ah pre-built 12v lifepo4 is now ~$270.

But the cheapest thing is always to get the most life out of what you've already got.