DIY Roof Mounted Solar Shower

Sara and I were driving through Santa Cruz yesterday and I saw one of these on a VW bus.  The design I saw yesterday was better looking than this and had a shower head attached.  Looked perfect for rinsing off after a day of surfing or kayaking!  Not sure if you have to pressurize it like the guy mentions in the video.  Wouldn't that happen from heat buildup inside of the tube anyway? 

I used to fill a sunshower and then put it on the roof rack while I was out paddling.
I saw some cool setups on jeeps back in the day that used the engine heat (from header pipes) to warm the water, and then a little electric pump to pressurize the water. They would just have to get a hose to the nearest lake

Not really sure why there would be a need for pressure.  Gravity works quite well.  The only issue I see, without looking inside the tube/valve, is that he will only get 1/2 the water out of it.  If the valve had a pic-up tume that touched the bottom, then I could see the need to add pressure to the pipe. 

Simple

I use this one....It literally get so hot I have to add cool water

yep, that's what I had as well EWB. They actually work great if the sun is out. Nice for remote car camping or kayaking.

When we would camp for weeks at a time @ Lake Sonoma, I rigged up a 360gph Rule bilge pump on a long hose & we would fill a small inflatable boat with water (on the shore), cover it with a small dark tarp & had bathwater for the evening!  WAS GREAT!!!!

 
  Piscean,  I had a heat exchanger on my jeep for a few seasons, it worked really nice for hot showers.  As long as jeep had gas and there was a water source, we could have hot showers on the trail!   Built out of 3" copper tubing, and 96' of 1/4" copper tubing in 3 separate coils all stuffed inside the 3" tube.  Worked so well we had a cold water bypass added to cool the output!  I like the idea of the pvc tube to rinse.  Can probably get 5+ gallons in one depending on size & length.

There's a pressurized device of similar construction...called a Super Soaker. You just gotta adapt the super-soaker technology to an enclosed 5-gallon bucket. And Bam = super soaker shower hack.