How to Build a Passive Solar Water Heater

Learn how to build a passive solar water heater. A solar heater can be simple to construct and reduce your utility bills. We’ll explore the various types of solar water heaters, and learn to build an easy and affordable model.

A “breadbox” heater (containing a single, horizontal storage tank) may supply all of your hot water needs for a season or simply “boost” or preheat water.
Illustration by John Canivan