Jeremai Cann will lead two workshops at The Green House on Saturday to teach participants how to create a “graywater” catchment system and how to use photovoltaic panels to make electricity from sunlight.

From 10:30 a.m. to noon, Cann will demonstrate how water drained from baths, showers, washing mashines and sinks can be reused for irrigation and other applications. The second workshop, from 1:30 to 3 p.m., will focus on designing solar photovoltaic systems for the home. The workshops are $20 each. Register online at www.thegreenhousehawaii.com or call 524-8427.