Installing Solar on the truck...

[Waterloo]

That Maxwell is worth the money eh? I have looked at them, pricey to say the least...

[Nilao]

It's been on the truck for about 4 years. Still kicks it off like a warm summer day even at 20 degrees.

[Waterloo]

(12-06-2020 )Nilao Wrote:  It's been on the truck for about 4 years. Still kicks it off like a warm summer day even at 20 degrees.

Good deal, come this summer I may pull the trigger on one, and more AGMs, as the solar is really impressing me.

[JimT]

I too have considered one of those Maxwell units. Problem is money, I could add 4 more batteries to my truck for the price of one of those. In fact I'm actually drawing up plans to add 4 more batteries so I can support the power needs of my new laptop over night (only gets 1-2 hours full to empty on its internal battery! ... playing games)

I have a portable fridge and my espar bunk heater running at night too. Leaves me at 12.2-12.4 in the morning, although with the key in the ACC position there could be additional power draw that I'm not aware of.

Also considering the solar route, but during the day I'm either on the road or parked at home with shore power. Rarely ever do a 34 restart away from home anymore, so I'm leaning toward the extra batteries.

[Waterloo]

My trick to stop unwanted battery draw was to take the items I use when parked off of the accessory switch and draw direct from the batteries. When I park, everything is off except for what I need, no need for the key to even be in the ignition. I have been parked for almost a week now, the APU is off, and the solar has kept everything up to snuff in regards to the batteries, saving fuel as the solar is working as intended.

[JimT]

(12-13-2020 )Waterloo Wrote:  My trick to stop unwanted battery draw was to take the items I use when parked off of the accessory switch and draw direct from the batteries. When I park, everything is off except for what I need, no need for the key to even be in the ignition. I have been parked for almost a week now, the APU is off, and the solar has kept everything up to snuff in regards to the batteries, saving fuel as the solar is working as intended.

Rewiring as you describe is on my long list of To-Do's... Eventually. Lots of other, more important things to do first. I also want to gut and redesign the interior of my 48" mid-roof sleeper, so I'll probably tackle the rewiring at the same time. (It's a remodel for functionality, not aesthetics. Lots of broken/missing stuff and wasted space) Figure I'll make a separate branch off the batteries for the inverter and all the sleeper DC electrical and espar heater. Then I'll have 2 cut-off switches, one for the sleeper, one for the rest of the truck. Finally I'll have my inverter wired to take in AC shore power, pass through to the sleeper and charge the batteries. Really, the only thing stopping me right now is time, and over a foot of snow outside ;)

[RocketScott]

Great write up and details

On boats that I work on we have two banks of batteries. One for starting and one for "house". The charge controller can handle the two banks independently. AGMs have typically been used for both banks but I'm looking into the newer lithium batteries to replace the house bank. They can run down deeper, take charge faster, and are lighter weight (not as important on a truck). I'm still trying to do the math to see what the cost difference would be. They cost twice-three times as much but since they can draw down lower than an AGM I should be able to reduce the total amp hours of the bank

Something to consider. My 379 has 4 group 31s that are probably close to end of life and I need to figure out what should replace them. One good thing is the recent camper van craze has lead to a lot of nerds figuring this sort of thing out

[Waterloo]

Well, back to work... Never give up your trailer at LandStar... I took a 34 day reset, not my choice... Anyhow, back at work, switched agents and am running freight terminal to terminal for ABF LTL Freight. Pulling doubles and 53' trailers and actually enjoying it. Now, the purpose of this post...

The truck sat in storage for a month, in Michigan, and I never visited her in that time period up until I found some work. I did that on purpose, even left the refrigerator on the entire time. And yes, I emptied it when I parked.

The fuel gauge did not move from the APU, normally it would have drank over half a tank or more after sitting like this. The batteries were at charge, 13+ volts when I got in, they were being maintained nicely with the solar panels. The truck fired right up, like she had only sat overnight.

I am on reset here in Little Rock, at the Petro, may take another day off and head out on Saturday. Still getting my truck legs back. The APU just turned on, first time today, it is 2330 hours. It ran for a bit yesterday, but not for long.

These panels have paid for themselves 10 times over. Just letting this truck sit for a month would have cost me time running up there every few days to start and let her run, and money from all of the wasted fuel from the APU, and maybe even a service call.

The one issue I have had, is seeing as the APU rarely ever runs, when morning comes, the engine block is cold. I have the TK APU plumbed into my coolant system. No APU running, means a cold start in the morning. But, I run my gear oil, and if you have ever cracked a motor that runs it, you will know that it leaves a nice slick coating on everything it comes into contact with. So, I am not to concerned about the cold starts.

If you are thinking, or are on the fence about installing these flexible solar panels on your rooftop, just do it, especially if you run a bunk heater or have a lot of electronics and a refrigerator onboard. Just my .02 as they were worth the time to install, and did not break the bank. I think you could do this for roughly $500 or less. I put roughly $750 in my setup, but can see now that $500 or less would do the same job.

[JimT]

Maybe if you find yourself with some extra time on your hands you can put together a nice little how-to with some amazon links for others to do the same. I know you had a pretty detailed write up earlier in this thread, but maybe a revised, polished version for anyone to apply to their truck? You could incorporate changes or fixes you've done or thought of along the way and maybe explain the design decisions so people have a better understanding of the choices and why. And yes, I'm probably going to follow your lead and do something like this for my truck along with an extra battery bank since I don't have an APU. Eventually...