chad duncan

I'm using the Bogart trimetric and I would recommend it.
It tracks actual amperage instead of generalizing with voltage. And it gives me a fuel guage like percentage of full to read.
Two thumbs up.

I've experimented a bit on heating tubs of water, sometimes successfully!
My water heater is a propane BBQ so things are a little different but worth discussing I think.
The first thing I learned was that insulating the tub of water helped more than adding copper tubing. My tub was built using 2x4 house construction methods with the corners braced with steel angle brackets. With a little forethought I bet ratchet straps would work too. The tub was lined on the inside with 2" construction Styrofoam and when I wasn't in the tub I had a layer of the same Styrofoam floating on top. The water was contained by a single layer of common tarpaulin (tuck the corners down as you fill or you risk tearing)

Having the copper tubing touch the steel of the stove or pipe will help greatly. Would you be able to solder the copper to the steel in a few places?

Inverters are not 100% efficient. They get more efficient as they reach their max output so you should size your inverters with care if pinching every last watt is important to you (as it is for me). More electronic cut outs and sensors and whatnot are just going to be more electrical draws.
Solar living has three main components:
1. lower your power consumption
2. increase your power production
3. increase your power storage.

for your fridge, I wouldn't complicate things with relays and voltage sensors and automatic cut outs. Increase the efficiency of the fridge with better and more insulation while making sure that the fridge can dump out the heat it makes through the coils on the back. Put your fridge on a timer so it only comes on during daylight (charging) hours and don't open the door outside of those times.

If batteries are unaffordable, lower your standards and run the batteries that someone else thought no good anymore and test them frequently. Keep the ones that work well, recycle the others. 'They' say that batteries are only good for a short number of years but this is not really true. With care a good battery can last as long as twenty years without too much loss of overall capacity. More importantly, a battery that is only holding 3/4 of it's original capacity is still a viable battery and rich folks will throw them away as soon as they are no longer 'perfect'. You will still get some valuable use out of them.

Off grid is cheaper at the initial purchase because the equipment that ties you to the grid is very expensive.  Another tidbit to consider with grid tied systems is that they shut down during a power outage (generally). this is to protect linesman from getting electrocuted by lines that are powered by the load side. For example, when a line breaks and hits the ground, one side is live and the other is dead. If your panels add power into the system,  the line that would typically be dead will now be live also,  or a line that was dead a minute ago could suddenly come alive as conditions at your panel change.

For what the OP is considering my advice would be to purchase a lower end solar charger and a used deep cycle battery or two. The batteries won't hold as much power as new ones but they will buffer the sporadic nature of the panels which are affected by everything from clouds to tree branches to bird poop.

Something else to consider if you want to avoid batteries and solar chargers is that a nominal 24v panel can run closer to 35v (Vmp, volts at max power production) in full sun and as high as 42v open circuit voltage (Voc, max voltage possible).
A couple of cheap deep cycle batteries (2 6V batteries in series) and a bargain bin charger can be had for under or around a hundred bucks and would be effective at protecting electronics and would allow you lights and laptop charging at night.
Good batteries would allow running the fridge overnight.
A good charger is great for maximizing storage of the energy harvested and for maintaining healthy batteries.

A little late for a welcome but I just noticed that you were the poster of a youtube channel I was watching (before I went off grid and lost my in house internet connection). Congratulations on not freezing through this last unusually cold PNW winter. I had hydro power last winter but this coming will be PV only. Anyways, Welcome!

Chad.

It would certainly be better to have a battery or two. Don't be afraid of using old batteries, they are not as great new but they are better than nothing. It's nice to be able to charge your laptop at night.
A lot of people say that you can not mix and match batteries but I have been reading a lot of scientific studies regarding this and it feel that it is simply not true.
Some rules need to be followed though:
1. Batteries wired in parallel must have the same charging characteristics. for example an standard lead/acid car battery may charge up to 14.8 volts while an AGM (also acid based) may only be good to charge up to 14.4 volts.
2. batteries wired in series should have the same amp/hour capacity.

Due to internal resistances one battery may release it's current sooner than the other (ex: a newer battery may partially discharge before the older battery parallel to it does, for early stages of the discharge) and this will cause the more used battery to 'wear out' sooner but not sooner than a single battery would have anyways.

Also, when the sun first comes up and the panels start to make voltage but before they produce amperage, they can create a momentary high voltage that could feasibly damage sensitive equipment. A battery bank would soften this.

My dexters don't care about the electric fence I put up, they walked right through it. We had to use page wire to contain them.

Rebecca Norman wrote:I don't understand what the shelves are in the photo of the trailer-coop above. For sleeping, chickens like perch bars, just sticks, not shelves. Shelves will collect inches and inches of poop.

A 2x4 on edge (1.5 inches) is perfect for most climates.  If you get exceptionally cold winters then the 2x4 set the other way (3.5 inch perch) will allow them to sit on their toes to keep them warm but the poop will pile up.

I agree with all of that.  I should add a clarification to what I said earlier about 12.5v not being enough.  When you set your mppt to the default '12v' it will actually charge it to a more appropriate voltage, likely around 14v. The mppt calls it 12v just to keep things simple for the user.