Age group: Venturers

How long it will take: probably a few weeks

What materials you will need: various

The aim of the activity: To learn about solar energy and have nice warm water at camp!

What to do:
Try designing your own solar water heating system for use at camps.

There are two different things you could do. One is to design solar showers and the other is to design a system to heat water for washing up etc.

For the showers what you need is a lot of pretty warm water, with a way of getting a spray high enough up to be able to call it "a shower".

For the washing up what you need is a fairly small amount of very hot water.

The standard sort of system for a house has a collector, which is where the water gets hot, and then the water passes to a tank, which ends up full of hot water. The collector usually has black pipes, insulation at the back and glazing on the front.

The tank is insulated and either there is a pump to get the water into it or the collector is below the tank and the water can flow upwards into it.

In a house the system gets automatically topped up from the mains. You need to think about how your system will fill up with fresh water.

You also need to think about how to stop the shower water getting so hot it burns people (this is very possible).

The simplest type of solar water heater is a dark colour hose that is attached to the tap and lies across the ground in a sunny spot. You then collect lots of clear plastic bottles all the same size. You cut the bases of each one so that they've still got the necks then you feed the hose through them one by one so that they fit tightly next to each other and form a glazed tube enclosing the hose.

You need a fitment on the end of the hose to control the water flow, of course. So the length of hose is storing the water.

How do you improve on this?
In order to increase the sustainability of the system it should be as light and portable as possible, so that you don't need a huge truck to get it all to camp.

The Leicester Venturers/DFs made a system last year and would probably be happy to give you some advice.