BYOWater solar shower design

[sparr]

The goal here is to provide a shower where a person can bring their own cold water to the shower, as much or little as they want, and immediately get access to that same amount of solar heated water, without needing any fuel or power. There are plenty of other options for showering with hot or cold water, but most of them require fuel or power or planning ahead for each hot shower.

The drawing is simplified to make everything 2-dimensional and without drawing various additional fittings and valves that would be in place for assembly/repair. 150ft of 3/4" hose should hold about 3 gallons of water, and with a clear cover over the hose to make a little greenhouse it should get hot enough in an hour or so that users will want to mix some cold water with it. Obviously this would only work during the day, but at night people would be welcome to preheat their own water to dump into the bucket.

The major downside here is that in order to avoid using a pump, the bucket has to be up high, which means climbing a ladder to dump your water into the bucket prior to showering. I might add a second bucket at ground level with a bilge-style pump to move the water up.

[Popeye]

If the hose is in a tight spiral the diameter of the spiral will be just under 4 feet leaving an allowance for wall thickness. However if the spiral is that tight you will lose about 3/4 of your absorbtion area. If you lay your hose on top of a bus or conex in an open spiral it will absorb better.
The next step would be to lay aluminum foil on the roof with 2x lumber or whatever on top of the foil and the spiral on top of the lumber. This will greatly decrease heating time.
However wind moving across the hose will steal a lot of your heat so you should build a frame around the spiral. A glass top on the frame would be nice.

[Jackass]

Or you can simplify things and just use one of these. Works all of the time and offers an especially luxurious shower after dark...

[Just_Joe]

...or you can simplify things even more by not providing hot water.
A cold shower in the heat of the day keeps you cool and tends to self limit water waste.

[LowePro]

Right, or 3 of these in rotation: 1 full heating up on top of the car, 1 in the shower being used, 1 empty ready to be refilled.

sshr.jpg

[Sham]

Right, or 3 of these in rotation: 1 full heating up on top of the car, 1 in the shower being used, 1 empty ready to be refilled.
sshr.jpg

After nearly 2 decades on the playa, I have come to the indisputable conclusion that this is the only way to go.
We have had new camp mates come in with drawings like sparr has done, and they simply don't work out. Scalding hot water needs to be run until it becomes usable. Complex valves and storage buckets confuse people and they are left on to drain on their own.
One well meaning camper brought a large drum of water and a propane heater. We ended up with a evap pond with 150 gallons of water to dispose of. Every issue was predictable, but for some reason hot water from a tank was a priority. Over thinking and OVER engineering will come along again.

[sparr]

Scalding hot water needs to be run until it becomes usable.

Hence the hot/cold (or hose/bucket) faucet, so it can be mixed for comfort like in a house.

they are left on to drain on their own

This system won't let a user drain the hot water, even if they leave the faucets on. A user can only use (or waste) as much water as they put in, always leaving a hose full of hot-or-heating water for the next person to use when they put in more cold water. That was the major motivation behind this idea.

[sparr]

1 full heating up on top of the car

This is how I baked the paint off part of my vehicle last year. I strongly recommend against putting a solar shower bag on top of a car.

[Ratty]

Did you take a look at the old threads offered at the bottom of the page. I like the solar shower for 120 people

[some seeing eye]

Hey OP,
Appreciate you undertaking complex playa missions and doing them!

Have you considered the advantages of bring your own solar shower (BYOS)?

Participants manage their own inexpensive and usable year around and for disaster, survival and camping prep, water supply, manage their own heating, mange their own shower head flows. You still have a formidable challenge managing the grey water!

Grey water can always use more smart innovation.

[Canoe]

Concept sounds interesting: you only get what you bring, and you're limited to what's already heated.

Thoughts

Two feeds to shower head. User chooses between:

• cold water only (at the temperature they brought)
• warm mix of hot/heated & cold, through an auto (no electricity) temperature mixing valve to prevent scalding and overuse of the heated water
• with a low enough set point, the water is warm enough for a shower, but limits how much of the heated water is usable by one person

User brings both:

• their own container with potable water, and
• their own container to catch and take away their grey water.

Overflow catch tray, capacity, spill risk, consequences (BLM), mitigation plan.

Solar hose can get very very hot. Perhaps too hot. Have a way to shade the hose if necessary.

Solar hose in frame with reflector behind the hose:

• have the frame aimable at the sun - one edge can sit on ground plus some inches against flood; has to be idiot proof - or policed - to prevent someone pulling the hoses out of the shower|frame when re-positioning
• frame with reflector inside on back and wind shield in front means it collects heat even on a cool day, dependent on cloud cover
• glass works well as wind shield - wicked moop issue
• teflon sheet works great as wind shield - costs tons
• plastic sheet also works to keep the wind off of the framed in hose - need sufficient space between hose and sheet to prevent melting

This could/would be a disaster if offering to the public.
If carefully and robustly engineered with paying attention to all possible failure modes (how?), I could see this working with a limited size camp.

[Token]

The most important design decisions for a BM shower:

1. Finding a palet or other surface to stand on while showering that is splinter-free.

2. Taking the first step out of the shower with a wet foot and not landing on playa.

3. Designing the shower so it can accommodate friends helping you scrub the booty-dust out of all the mystery spots on your person.

4. Deciding where to put the bleachers so you can heckle the prudes as they scub their private bits.

The best part of showering at BM is stretching them boundaries!

Make it fun.