The right bus 😑

[Parkland]

So I was just thinking about the power system .... definitely going to need heat, ac, power, and hot water for showers and sinks .

I was looking at Espar hydronic heaters, different generators both propane and diesel, and options of a motor driving an alternator on demand to keep batteries full.


After crunching numbers and doing some math, it doesn't seem like a practical idea to charge batteries with an alternator just to turn back into 120vac to use. Out of fairness, if it's cold out and heat is needed, even an inefficient system like that might be pretty good because the waste product is heat, which is needed. But, hard on equipment.

Like I said before, I would love to try a changfa diesel as they are water cooled 1 cylinder and range from 3 to 20 hp. Waste heat from the engine can be used for the glycol system in the bus where an air cooled engine it's wasted. If I make a heat exchanger for the exhaust, it could make an extremely efficient system for cold weather.

So here's what I was thinking.... I'll start by installing 4 deep cycle batteries as the one and only battery bank. I know that isn't normally done.
I'll have maybe a 5000w inverter connected to the batteries. This will power everything.

I happen to be handy with computer programming so I'll find a cheap small android based board to control things here. So when the battery voltage gets say 60%, or the amps drawn reach 100 for more than 5 minutes, the computer will start the changfa diesel motor.
This diesel motor will drive an alternator and generator head with a belt. The engine will start and slowly get up to operating rpm. After 30 seconds or so, the computer will activate a relay that switches the 120vac bus power from the inverter to the generator head. Now, it will stay in this mode until the batteries are full and load is less than 200 watts for 5 minutes.

By doing this, the system should be totally automatic and seamless.

I'll have a glycol loop in the bus for heat and hot water. I will install 1 or 2 1500w electric heating elements in that loop, that way it will load the motor up to generate more heat when needed. I'll also need an external fan and radiator, for if the motor is working running the air conditioner or other big loads and there is no heat requirement.
Maybe the bus engine and rad would be enough to cool things just by radiating heat.

I think this would work great as the batteries and inverter would just handle smaller loads, then high loads for a minute or so until the generator took over.
I think this will also save a lot of fuel over leaving the generator run all the time.

It would be perfect with kids and family stuff because it should just work as long as nothing fails.

[TrailLifeBill]

Originally Posted by Parkland

I was looking through here and noticed that some people removed the inner paneling and put foam and renovated from there. Does the inner paneling not hold the wall beams rigid at all? Just wondering if some structural integrity is lost with removing the inside walls or ceilings .

I think the biggest reason to remove the inner wall and ceiling skins is to eliminate thermal bridging. We are in a tin can, basically - very strong, but very cold in the winter and very hot in the summer. Yes, some structural strength is probably lost. However, the inner skin is the weakest component of the outer skin/ribs/inner skin sandwich. And - as my reasoning concluded while pondering the same issue - what remains is significantly stronger than any RV/automobile alternatives I would put my family into.