In this technical illustration for Solar Today Magazine, I show how some passive solar heating systems can work in a house. I used arrows to show the flow of fluid through the various systems and color coded the fluid to show their temperatures. Hot fluid from rooftop solar collectors flow through a heat exchanger, transferring heat to fluid to flow through tubing in the floor. Direct solar gain through windows in the winter is shown, as well as how the roof overhangs blocks undue heat gain in the summer.
Like all of my technical drawings in this series for Solar Today, I used a crisp style, but with some sketchy linework accents as a nod to an earlier time when you had to project lines toward vanishing points by hand.