Hi Rookie35, While looking for a fan and controller, I came across Solar Air Systems' computer chip fan controller that comes equipped with a thermocouple that ramps the fan up when sun is at full strength and ramps down or shuts off completely as the sun's intensity decreases -say if a cloud passes...

Hi Rookie35, I liked your solution for passive solar heating. I had built several models in the past -including one soda can heater and a downspout style plenum. Both of these were a major pain to build, both were heavy and included glass and wood. I used to fabricate industrial ovens back in the da...