Need the solar/power pros to weigh in

shade

Well-known member
Water heater update. 5 hrs 45mins in and the water has risen from 18C to 31C. This is all happening in my garage which is 12C. I imagine this will do what I need; give me hot water for a shower after a day of mountain biking or sloppy fishing in warmer temps (above 65 I would think). Any colder and I’m going to seek an indoor shower. I will need to give this a field test but it will be quite a while before it’s at least 65 out for 6 or more hours. I am impressed with how well it has worked in the current test scenario.

View attachment 553542
Can you wrap some insulation around it where you normally carry it? That would likely make a significant improvement.
 

TantoTrailers

Well-known member
Can you wrap some insulation around it where you normally carry it? That would likely make a significant improvement.

Damn good idea! I wrapped a sleeping bag around it for the remainder but as I sloshed around the water inside the temp went over the 33C cut off I set so I upped it to 35C (now 6hrs 45mins in). I’m happy with these results, now I just have to make sure my panels can output enough power for this and charge my battery. I have never seen the controller take more than 100w even though I have 240w in series with my panels and I’m showing the correct voltage with a multimeter and at the controller so I think things are working right. We discussed in this thread that I just haven’t given the MPPT a good run for it’s money so this may be it. I’ll hook it up next weekend when I get out to test the cabin heater to see how it does with the solar.
 

TantoTrailers

Well-known member
Well, 8 hrs and I got up to 33C at the sensor with warmer and colder pockets mixed in. To be fair the temps were dropping in the garage down to about 9 or 10C. In warmer ambient temps (and sitting in the sun) I think this will heat up much faster. I will make the temp sensor cable longer and figure out a way to make sure it’s in the middle or opposite end of the tank...maybe a long skinny spring around the cable or just fish tank tubing for rigidity. I’ll call this an acceptable success.
 

luthj

Engineer In Residence
There was some discussion about that previously in the 12 volt forum. They are very expensive new. And have fairly significant current limits for people that need high discharge rates. They appear to be well-designed and can be chained together for various configs. Note that you do need a separate BMS master controller and disconnects which adds significant cost.
 

TantoTrailers

Well-known member
I’m just tossing around ideas for my next build which will be a 5x10’ off road rig. Tanto Fallout or something like that haha. I’ll definitely be going lithium on that build but that part of the build is at least a year off.
 

luthj

Engineer In Residence
It really depends on your needs . There are great deals to be had if you don't mind assembling your own pack . Otherwise the drop ins are a good option, especially if you don't need high discharge or charge rates.
 

TantoTrailers

Well-known member
I need to figure it all out because I want to make this a doomsday rig which will be fully self sufficient indefinitely. Not exactly practical in a real doomsday scenario but that’s what I’m going for in terms of functionality so I need to figure out everything I need first. Not making a fortress but I will be lookin to have many comforts of home including hot water with tanks installed underneath. I would consider getting 2 600w solar blankets.
 

shade

Well-known member
I need to figure it all out because I want to make this a doomsday rig which will be fully self sufficient indefinitely. Not exactly practical in a real doomsday scenario but that’s what I’m going for in terms of functionality so I need to figure out everything I need first. Not making a fortress but I will be lookin to have many comforts of home including hot water with tanks installed underneath. I would consider getting 2 600w solar blankets.
If you're thinking in those terms, +300W rigid residential panels would probably be a better choice.
 

TantoTrailers

Well-known member
The issue I have with rigid is where to put them. I use my roof rack for kayak at the very least and I would like to ultimately be able to carry 2 up there so the solar would be either under the rack rails (which at camp the yak is usually down on the ground or in the truck bed) or on the slanted down front part. I will have 2' extra roof front to back but I wont be any wider side to side. The rails would result in a 1-2" shadow across the panels width wise.

2.0 will be a crowd sourced idea, I will post up the whole build process and take input along the way so this is all very fluid and in the earliest stages of planning.
 

Forum statistics

Threads
185,842
Messages
2,878,770
Members
225,393
Latest member
jgrillz94
Top