What is a solar fruit dryer

It is a way to use the heat of the sun to generate a draft, which passes over whatever it is you are trying to dry (i.e. fruit, veg etc)

Design considerations

The dryer can be made in many different ways, so I will keep this generic so we can keep an open mind to how to design it for the specific venue. The key elements we need to discover are

  1. The shelving
  2. The container
  3. How to create a draft
  4. How to prevent insects and animals from getting in
  5. Can we make it adjustable to compensate for the moving sun and different sun angles

Materials

Shelving

This needs to allow air to pass through, but strong enough to hold the fruit. So can be a wire mesh; plastic mesh; cloth. All have pro’s and cons (to be discussed as we design)
Something to give the shelf a form i.e. a frame. Most likely from wood or metal

Container

Some way to house all the shelving, and protect from insects and animals. This could be any box shape. Could for example be a cabinet, or a chest of drawers, or an old hifi case. Or it can be made. There needs to be a door to allow you to get the fruit in and out.

Draft generator

Not sure what to call this, so I will call it a draft generator. Draft can be made in many ways. You can heat a box and force heat to rise (a solar collector), or you can make a heated chimney and suck air up (will discuss the differences during the design). Invariably we will need some glass or plastic sheet for this. If this is a separate unit, then we will need a box to make housing. Or it can be part of the main container. To accelerate the draft something reflective could be useful, so tin, mirrors or aluminum foil. If we use a separate solar collector we could use tin cans painted black to.

Photos

Google search on passive solar dryers