Portable camping shower

I am a Product Design student in Liverpool, England and have been set
the task of designing an 'Eco Friendly' shower. Me and my three fellow
students have come up with an idea for a portable shower that is to be
mainly used by campers and recycles water without the need for a non
renewable power source. Our idea is as follows:

- The shower system folds up into a briefcase sized box and is
accompanied by a blow up shower cubicle.
- The user unfolds the shower base out of the box. It consists of a
base that contains two foot pedals that the user stands on while
showering and a control panel with a heat switch and clean rinse
option. There is also a retractable shower pole that erects into a 6-7
foot pole with the shower head being fixed ontop.
- The theory behind the design is that the user slowly pumps the water
around the system with their feet, which provides the power for the
water to be moved around the system.
- The user blows up the shower cubicle which is around 8 foot tall and
hollow.This can be done by either manually blowing up the tent cubicle
(which may take some time) or by connecting it to the shower and using
the showers built in pump to fill it up that way. The shower base is
then put inside the cubicle and folded out into the starting position
before the shower begins.
- When the shower is in use and water falls from the shower head it
lands inside the blow up cubicle and is sucked up by valves in the
feel on the base that then sends the water round the cycle again
- The water is heated by a small gas heater
- This process can continue for as long as the user wishes, aslong as
they continue to slowly pump, the hot shower will continue and there
is no time limit because most of the water is being recycled.
- When the user feels they are fully washed they can select the "clean
rinse" option from the control panel which then takes water from a
small water tank of clean water, providing the user with a short clean
wash before they leave the shower. This will get rid of any dirt that
may be left on the body. This rinse will only last for a few minutes
as this water will not be recycled. It will be pure and hot and used
only as a quick rinse at the end of each wash.

The reason I have posted this message is to get a general feel for how
people may react to such a design. Are there any major doubts people
would have about possible issues raised? Would people be willing to
slowly pump for the duration of their shower if it ment the shower was
hot and cud last as long as the user wished? Would anyone have a
problem in washing in recycled water? I would very much appreciate
anyones thoughts, comments and questions. Thanks for reading this
message, hope to hear from you all soon.