Abstract: A solar energy collecting and storing unit comprises a single housing having a glass-covered collector chamber on one face of a gravel-filled heat storage chamber, the chambers being separated by an insulated partition. The collector comprises an array of L-shaped metal fins over which air is caused to flow in a predetermined path by baffles. A first air flow circuit between the storage chamber and the collector chamber picks up heat absorbed by the fins and transfers it to gravel in the heat storage chamber. A second air flow circuit transfers heat from the storage chamber to the building to be heated.