Some cool solar heating systems images:
New Solar Heating System

Image by Abri_Beluga
Anna with friends and family in front of their new Solar Water Heating system
John Keyes, president of International Solarthermics Corporation, shown with the backyard solar heating system he developed…, 05/1975.

Image by The U.S. National Archives
Original Caption: John Keyes, president of International Solarthermics Corporation, shown with the backyard solar heating system he developed. The a-frame structure contains the collectors (behind the glass plates), reflector plates (snowcovered plates on the ground) and storage system that includes several tons of one inch sized rocks to store heat inside the a-frame. This unit is connected to the home heating system by an insulated underground duct, 05/1975.
U.S. National Archives’ Local Identifier: 412-DA-14860
Photographer: Norton, Boyd
Subjects:
Environmental protection
Natural resources
Pollution
Nederland (Boulder county, Colorado) inhabited place
Persistent URL: research.archives.gov/description/557312
Repository: Still Picture Records Section, Special Media Archives Services Division (NWCS-S), National Archives at College Park, 8601 Adelphi Road, College Park, MD, 20740-6001.
For information about ordering reproductions of photographs held by the Still Picture Unit, visit: www.archives.gov/research/order/still-pictures.html
Reproductions may be ordered via an independent vendor. NARA maintains a list of vendors at www.archives.gov/research/order/vendors-photos-maps-dc.html
Access Restrictions: Unrestricted
Use Restrictions: Unrestricted
New Solar Heating System

Image by Abri_Beluga
Solar Water Heating System Installed on Anna’s house’s rooftop. Produces 55Lt of hot water every day.