Anyone used solar water heating on their bus conversion?

[NewbeeMC9]

a

b

Exactly!!!!

I believe we all concur

[Old Scool Bus]

I've done this, tried to post pictures but too big and the photo bucket link didn't work

[Old Scool Bus]

Not plumed yet but during pressure test in indirect sunlight on 70 degree day water temp got above 200 degrees

This along with some mods to my pellet stove in both size and function will assist my proheat. Hopefully make the Proheat more of a backup system.

[Old Scool Bus]

Solar PV panel

[Iceni John]

Not plumed yet but during pressure test in indirect sunlight on 70 degree day water temp got above 200 degrees

Yikes!   That shows there is more than enough solar energy most of the year (at least in SoCal) to produce significant heating.   Is your panel home-made or commercially-produced:  what make is it?   What is its internal design?   How do you circulate the water through it?

Tell us more.
John

[Old Scool Bus]

Commercial made, no reason to take apart so not sure of internal makeup but did see several at a salvage yard that had broken glass and were copper across both ends and black plastic running between them. No name on mine. It was never used picked it up on CL in Boulder, Co for $30.00.

Not plumed as of yet but have a 12 volt pump I bought from Harbor Freight I plan on using, but may have to go with one I saw at the alt energy fair in Fort Collins made for this specific use because of temp issues. Need a temp controller for proper circulation.

Don't plan on heating bus with it but using for domestic hot water. Will eventually plum it with capabilities of heating engine and tied in to proheat and use it as a controller but through FPHE or valves

[PCC]

Using solar heat for water has pros and cons.

Including solar heat into a heat exchanger is the safest configuration, because if there is a solar panel leak, you do not lose your water supply, nor is your domestic water contaminated by anything that might be introduced due to a puncture or other damage to the solar collectors.

Using the solar to preheat the engine is a thought, but if it is warm enough to heat the water system, the engine should be warm enough to start.

On the other side of the efficiency spectrum is using that same heat exchanger tank to take engine coolant and transfer engine heat, or generator heat to keep your hot water hot during travel, and all you have to do is insulate it well, so you have hot water upon arrival. That is also a savings,

Using the exchanger and a 12/24v pump to circulate water into your hot water tanks, which are then well insulated will give you hot water as long as either engine (water cooled, of course) is running, meaning that the hot water tank heaters will only operate when neither engine is running.

Savings there will be considerable, and the up front cost will most likely be less.

This system also works in reverse, if you have an electric pump on your engine/s coolant/s. Operating your pump on the engine/s will raise the temperature of the coolant by taking heat back from the exchanger because of your hot water tank circulating pump.

Just my thoughts. I can heat up to 150 gallons of water on a 50 mile trip.

[cody]

Years ago we followed a design from Mother Earth News and used it to heat a 24 ft above ground pool for the kids, the panel was about 8x12 and it was layed on the roof of a shed by the pool facing south, it was powered by a circulating pump from a furnace and kept the pool heated nicely all summer, we used it for several years until we got rid of the pool.  I set up the water pickup by the botttom of the pool and the outfeed by the top and it worked well to keep the water from layering in the pool too.

[NewbeeMC9]

I've done this, tried to post pictures but too big and the photo bucket link didn't work

Yeah, that's a pain sometimes.     

Welcome to the madness!!!   Looks like your coming along well.

[daveola]

I'm thinking of just running some of my cold water supply through a simple heater using some black pipe or hose in a lexan covered box on my roof and then running it down to my ProHeat heat exchanger.

In other words - no collection or pump needed (it would just use the pump/pressure of the cold system and only
circulate when I pulled hot water out of it).

My thoughts are that it would be very simple and cheap, and it would give me some free hot water up front, possibly enough to shower and not even need to turn on the proheat - and if it doesn't have enough for that, then it can at least give me some warmer water until the proheat warms up.

I might need a temp balancing valve to deal with the temp changes as the solar runs out of heat and as the proheat starts warming up, but it seems like a workable system.  Any thoughts?  I was figuring something that would heat up 5 gallons or so of water by about 40 degrees would probably make a reasonable shower for a couple of minutes, so maybe 4 or 5 square feet of piping?

[daveola]

Just an update, I decided to go ahead and try doing a loop of ABS from my normal cold water supply to the input for my shower.  It works great when there's *no wind*, but wind is able to take all the energy away, so I need to box it in with some sort of clear top at some point.  I can hold something like 10 gallons up there, so it's enough for a nice warm shower for a few minutes.

At some point I need some way to bypass the system and drain the water back into my tank so I can go to freezing climates.  I'll put info on photos at some point up on my site.