Making passive solar space heaters

By Eric Smalley

On November 16th, we were fortunate to have renowned woodturner and GreeningRozzie board member Beth Ireland lead a workshop on making passive solar space heaters. Twenty of us gathered at the Roslindale Community Center and learned to use hand tools.

We made 12” x 24”wooden boxes and we painted aluminum cans black.

We painted the interiors of the boxes black, put the painted cans in the boxes and covered the boxes with Plexiglas.

Placed in a South-facing window or other sunny spot, the heater emits a stream of warm air. The black paint absorbs sunlight, which warms the cans and the interior of the box. This warms the air inside the heater, which rises and exits through a hole at the top of the box. A hole at the bottom of the box lets air flow in, which allows a steady circulation through the heater.

Here’s a how-to video for making similar passive solar space heaters.

Here’s blog post by GreeningRozzie intern Hannah Pullen-Blasnik about passive solar heating.